Astrology

History of Astrology

Astrology has existed, in some form or other, for over 3,000 years. More than a few of the greater minds of civilization, Western or Eastern, have taken it seriously. For many centuries it was barely distinguished from what we now call "astronomy"; in fact, astronomy was developed in part to allow the making of astrological predictions. The great astronomer Kepler was also an adherent of astrology, writing that "one should only disbelieve in idiocy and blasphemy; from the astrologers a useful and healthy wisdom can emerge." Even Newton showed some sympathy with astrology, though he hid it out of fear of religious persecution. And, much as our presidents now have economic advisers, monarchs and popes often used to employ an astrologer full-time to help guide them in the making of important decisions; the office of 'Astrologer to the Royal Court' was thus a potentially powerful position. The present version of astrology, developed by the ancient Greeks around 400 B.C., was codified by Ptolemy in the second century A.D. in his Tetrabiblios. So astrology's basic text has remained pretty much unchanged during the last 18 centuries.

Basic Principles

Look at the sky on a clear, dark night. The impression one may get is of many points of light pasted on the inner surface of a great hollow sphere centered on Earth. As the world turns, this celestial sphere appears to turn daily around Earth's own axis of rotation. The stars seem to rise and set, but there are many fixed constellations in which the stars relative positions remain constant. The planets Mercury, Venus, Mars, Jupiter, and Saturn, all visible to the unaided eye, seem to move with respect to the fixed stellar background. Their movements all appear to be in roughly the same plane as that of Earth's motion around the Sun, a region that forms a belt, centered on the Sun's path, around the celestial sphere. According to astrology, this celestial belt is divided into twelve equal regions, represented by the twelve signs of the Zodiac. In order from East to West they are Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius, and Pisces. (It takes about a month for the Sun to move through each region.) During the calendar year, each of the planets and the Sun are in one or another of these regions. For example, on July 12, the Sun is in Cancer; on May 11, the Sun is in Taurus; on February 23, in Pisces, etc. This gives us a crude coordinate system for locating the planets and Sun with respect to the stellar background; a bit more work is required to figure out how the planets and Sun are oriented in the Zodiac relative to points on Earth from which they may be observed. From Earth, the celestial sphere seems to rotate about Earth's axis; this is why heavenly bodies appear to rise (in the East) and set (in the West), gradually moving across the sky. The 12 astrological houses are simply stationary regions of the sky, fixed with respect to the horizon, that can be used to locate planets and signs relative to the Earth's vantage point. To determine a person's natal horoscope one maps the locations of signs and planets in each of the twelve houses not only at the time of that person's birth, but also from the vantage point of that person's birthplace. It is a rather elaborate and somewhat arbitrary coordinate system for locating some heavenly bodies relative to a person's birthplace and date. So far, so good.

Astrology's main interest derives from its assertion that certain physical and psychological characteristics are associated with each of the signs and planets and that each house governs some aspect of a person's life. So, for example, the first house is alleged to control temperament and personality. If Mars, the Roman god of war, is in that house, the individual is likely to be aggressive; if Aries, the sign controlled by Mars, is also in that first house, astrology would predict an extremely aggressive temperament. Of course, scores of other factors may operate in a natal horoscope and hence astrology is not committed to predicting that the individual with Mars and Aries in the first house is bound to be, say, an axe-murderer; if in addition the tenth house, which controls career, were inhabited by Neptune, a water (or wishy-washy) planet, a planet therefore associated with indecisiveness, that aggressive person might never be able to make up his mind whom to attack. Interpreting a chart and weighing all of the simultaneous influences is therefore a complex matter indeed. Nevertheless, it is sufficiently well-ordered by rules of interpretation that much of the task can be done efficiently by a suitably programmed microcomputer. As the world turns, so the home front soap opera evolves.

Notice that what we have said so far about astrology means that the Daily Horoscope columns in newspapers are, by astrology's own lights, bound to be misleading at best. All they deal with are Sun signs, but many other influences are present in each individual's chart, and all of these must be thrown into the mix before one can hope for reasonably accurate predictions. If we're to be fair, we can't judge astrology by its worst practitioners.

Is Astrology Pseudoscience?

Let's look at some of the criticisms that have actually been made of astrology. Keep in mind that we are concerned with the question, What is the difference between science and pseudoscience? We must understand that question in the right way if we are to find the kind of answer we want, namely, some principle that will help us decide when not to bother investigating. Most of us share a strong conviction that not every explanation, hypothesis, or theory is worth attention in a science course. If I tell you that my wrist watch is run by invisible gremlins, you're not likely to apply for a grant to check the hypothesis. This is different from the situation we're in when someone offers an explanation, we don't know whether it's true, and it turns out on investigation to be false. Many works of genius have turned out to be wrong in the end. No one wants to say that Newton was a pseudoscientist simply because Newtonian mechanics, his theory of gravity, was wrong. So our primary concern here is with a gatekeeper that can tell us what is investigation-worthy and what should be locked out. Does astrology qualify for the race?

Many scientists and skeptics have asserted that it does not qualify. We'll look at four of the many reasons that have been offered.

I mentioned Mars, the god of war, in my description of astrology's basics. When the ancients examined the planet Mars (no telescopes then), it appeared red. This reminded them of blood and war, so they supposed that it was the home of the deity in their polytheistic religion who was in charge of war. The planet was actually named after the deity and gained its astrological association with aggressiveness in this way. So unless you worship Mars, Zeus, Mercury, Neptune, and the other gods in the Greek or Roman pantheon, you've little reason to be sympathetic to astrology. If, like most people nowadays, you regard ancient Greek and Roman polytheism as at best interesting mythology, then you may instead be persuaded by the first criticism of astrology:

Astrology is a pseudoscience because it originated in the superstitions and belief in magic prevalent in ancient times.

Astrology did originate in this way, but so did astronomy, with which it was closely allied for many centuries; and the same is true of chemistry, with its origins in alchemy (the attempt to transmute lead into gold by discovering the fundamental animating principle of matter); and of modern medicine and biology. They are not on those grounds pseudoscience. Nor should this surprise us. Ancient religions were the first systematic attempts to make sense of the order and disorder in the world. From where else could modern science have developed? Perhaps, for all this criticism says, astrology has transcended its magical origins.

The first criticism focused on a narrow portion of astrology's history, and it failed. Taking into account a larger portion of its history may yield a better criticism, so let's take all of astrology's history into account. I noted that astrology's basic text, Ptolemy's Tetrabiblios, was about 1,800 years old. Suppose you enrolled in a physics or biology course in and found that the instructor had assigned an 1,800 year-old text. You would, I think, look for another instructor. Science is marked by rapid change and progress. The rate of change is now so great that scientists are forced to subsubsubspecialize, and even then they can barely keep up with the books and journals directly pertinent to their restricted domain. A rough, simple rule-of-thumb measure of progress in any specialty in science is the number of linear feet of library shelf space the specialty's published output takes up annually, plotted over the specialty's lifetime. For any established modern branch of science, the slope of the resulting curve will be pretty steep over the last decade or so. Astrology, however, does rather poorly in this test, having been stuck at about two inches for the last eighteen centuries or so.

Astrology is a pseudoscience because it is stagnant - it has shown no progress during the past 18 centuries; science shows progress.

This criticism of astrology is not factual. In the first place, astrology has not been entirely stagnant. When Uranus, Neptune, and Pluto were discovered - only after the invention of the telescope - astrologers modified their schemes to take these planets into account. And during the past forty years, many new systems of astrology have been developed, many more complex than their predecessors. In the second place, why would great change or progress be expected if the theory is correct to begin with, or well along the right track? The principles governing chemical interactions have been known for some years, and while great progress has been made in their application, the basic principles haven't changed much. Does that make chemistry a pseudoscience? Of course not. Suppose that in some specialty in science we actually discovered the relevant truths and were able to explain them: further change would be regress, not progress. So this second criticism of astrology would imply that the most successful science was pseudoscience, exactly the opposite of the result we want.

Generally, historically based criticisms will tell us little that settles the scientific status of a theory. So let's take a closer look at the theory itself - never mind when or where it grew up, or what it's been doing since then.

According to astrology, distant physical objects exert a profound influence on you at and after the moment of your birth. Of the four known forces in nature - electromagnetism, strong nuclear, weak nuclear, and gravity - only gravity could have such influence over such long distances. Could the force of gravity carry astrological influences? Pretty clearly not. There were many objects close by when you were born that exerted comparable gravitational force on your infant body, but about which astrology is silent; for example, there was your mother. So it can't be gravitational force that carries astrological influences, which means that none of the known forces of nature is responsible.

Astrology is a pseudoscience because there is no known physical mechanism for the influences it alleges; it claims that the very weak forces exerted on us by the planets can strongly influence our lives and characters, but our current science allows for no such physical possibility.

This is wrong on two counts. First, since organisms can be extremely sensitive to very weak forces, the suggestion cannot be ruled out as physically impossible. Homing pigeons, for example, are thought to navigate by detecting small point-to-point variations in Earth's already rather weak magnetic field; the large literature on biomagnetism contains many other examples. Second, many scientific claims are made in the absence of any known underlying physical mechanism. When the theory of continental drift was first proposed, drift could not be explained by any known mechanism; plate tectonics came later, after the view of Earth as a rigid ball of rock was replaced with the more accurate picture of a spheroid of highly viscous fluid on which the continents float. The term "gene," for the unit of heredity, was coined and a fair portion of its theory proposed well before the advent of modern molecular biology. And few doubt that there is a strong causal connection between smoking and lung cancer, but no one knows the precise causal mechanism involved - because no one knows the details of carcinogenesis. The fundamental error in this criticism of astrology is to look at it only in terms of a part of science, the part that explains by means of laws and theories. But there's another part: discovery of new phenomena that have yet to be explained.

The last criticism of astrology that I want to consider is the most common. It has a number of different motivations, but all aim to show that astrology is not testable.

I have heard critics say that astrology is not testable because it is not based on observation. Where, the critics ask, are the observations of human behavior under planetary influence that would be needed to sustain astrological theory? And then there is the language of astrology, which, being largely the language of human thought and emotion, is shot through with vagueness. Just think of all the ways in which feelings may be manifested and how easy it is to make a mistake about someone's emotional state or thoughts. Since the predictions of astrology use such language, we're unable to tell what they say, and without a well-defined target, one can't distinguish a hit from a miss. Finally, there is the behavior of astrologers, who are forever excusing their missed predictions. If you've ever seen a sharp reporter take on a slippery astrologer, you know how the conversation goes. Every challenge is met with some new, previously ignored factor from the progression of the person's horoscope, and the result is that one never gets a settled, definite prediction about what the person's life will hold.

Astrology is a pseudoscience because it is not testable: it is not based on observation; because of the alleged complexity of natal horoscopes, any missed prediction can be excused; and its terms are too vague to yield definite predictions.

This is one of the most common charges against astrology, and it is also one of the most ill-conceived. In a perfectly reasonable sense of the phrase, astrology is 'based on observation', namely, on observation of the relative positions of certain heavenly bodies (and remember that telescopic observations resulted in revision of astrology). "But," you say, "it's not based on observation in the right way!" Good point - or it would be if you could tell us what, in general, the right way is. (As we'll see in a later discussion, the link between theory and observation is more indirect, complex, and circuitous than many critics of pseudoscience have thought.) It is true that many of the terms of astrology are somewhat vague, but we're accustomed to working with vague terms and seem to do quite well with them. Many of astrology's vague terms do indeed come from our language of character description. "Angry" and "aggressive" are vague terms, but we can apply them quite reliably. Nor is astrology unique in being infected with vagueness; even biology, clearly a science, has trouble with "living thing" - are viruses to be included or not? Maybe astrology is vaguer than biology, but that may simply reflect its subject matter: predictions of human feeling and action. Can any missed prediction be excused? Not if astrologers respond honestly to the questions put to them; and some of them do: they sometimes make fairly specific predictions about an individual's character and life. Besides, what's at issue here is not the moral character of astrologers. Any theory can be misused, and the fact that astrology may sometimes be misused by some astrologers is irrelevant to that theory's scientific status. We might as well condemn Newtonian mechanics as pseudoscience because it has been used to guide weapons of war. The main problem with this criterion, though, is that it sets standards that are far too low for scientific status. Although it is possible to concoct hypotheses that are in no conceivable way testable, it requires something of an imaginative stretch (see the discussion of Ruse's criticisms in Scientific Creationism in the Courts, for example). Almost any hypothesis or theory that is someone is likely to think of will be open to some sort of conceivable experimental test, will be tied in some way to observation. Certainly, astrology passes this test with flying colors since many of its predictions have actually been shown to be false.

Other charges have been made against astrology to show that it's pseudoscientific, but this is a fair sample. And none of the principles in this sample show that astrology is a pseudoscience.

None of this is to say that astrology is a correct theory of human personality and behavior. It may be a tissue of falsehoods. In fact, statistical studies have turned up plenty of evidence against astrology, and no good evidence for it. So it is surely wrong. But that wasn't our question, and it's not the main charge made against astrology by many of its critics. They claim that it doesn't qualify for the race at all.

In the case of astrology, we may not care much whether it is pseudoscience or scientific-but-false. After all, the view, despite its popularity, is pretty clearly bunk. But we can't always afford to be indifferent to such matters of principle, especially when we are confronting a controversial view or are entering a gray area between clear investigation-worthiness and clear crackpottedness. The lesson of astrology may be important not for what it teaches us about astrology, but as a warning that those matters of principle are less straightforward than they may have seemed.

Phrenology

Our next allegedly clear example of a pseudoscience is phrenology. Crudely put, phrenology is the attempt to determine a person's character by examining the bumps and pits on his or her skull. Although many of us might not like to admit it, we do often judge someone primarily by his or her appearance, despite the fact that we ought to know better. In studies done by social psychologists, subjects have been found to rely primarily on the incorrect equation "intelligence = beauty." In some ways, phrenology is simply a more precise form of the common underlying prejudice that you can judge the contents by the package. But there is much more to phrenology than that. To see what more there is to it, we need to take a brief trip through the history of neuroscience. It will turn out that, for all its errors, phrenology had important hypotheses to contribute to modern neuroscience. It is recognized that no history of the development of modern neural science is complete without a discussion of phrenology. Of course, there are two sorts of reasons why it might deserve such discussion: phrenology may have had no correct and important content, but profound effects; or it may have had effects because of the importance of its content.

One nineteenth-century writer offered the following comparison:

[Phrenologists] ... may be compared to the old man in the fable, who assured his sons, on his death-bed, that a treasure was hidden in the vineyard. They began immediately to dig over the whole ground in search of it; and found, indeed, no treasure; but the loosening of the soil, the destruction of the weeds, the admission of light and air, were so beneficial to the vines, that the quality and excellence of the ensuing crop were unprecedented. (William Lawrence, quoted in Young, 9)

This is a fair description of the relationship between astrology and astronomy. Let's see if it holds for phrenology, or if there is more to phrenology than this comparison suggests.

History of Neuroscience: The Brain Hypothesis

The belief that mental function is located primarily in the brain has not always been held and is certainly not obvious. (Suppose you were challenged to prove it, from scratch, with no textbooks in which to look up the answers. It's not immediately obvious how to proceed, is it?) From about 500 B.C. to A.D. 1500, there was debate over whether the heart or the brain was the location of the mind. The ancient Greek scientist and logician Aristotle argued (around 350 B.C.) that the brain served merely as a radiator to cool the blood; he gave pride of place to the heart, which was a detectably warm and active organ. Although he knew that human brains were larger in proportion to body size than other animals' brains, he thought it was because humans had richer and hotter blood and so needed the better radiator. He also knew that most of the waste heat that people lose is exhausted through their heads (so parents' advice to kids to "keep your hat on - it's cold outside" actually has a basis in fact, unlike much of what worried parents say). There were other ancients who held the brain hypothesis instead, and who sought to support it with observation. Galen (A. D. 129 - 199) was an early practitioner of sports medicine, as doctor to the Roman gladiators. He saw plenty of brain injuries, noted their effects, and argued for the brain hypothesis. Although the cardiac hypothesis is no longer taken seriously, it has left its mark on our language for describing our emotions: love is a heart pierced by an arrow; people are said to be heartbroken; the apathetic don't put their hearts into it; angry people sometimes say, "That makes my blood boil."

The modern debate about the nature of mental function begins with the great seventeenth-century mathematician, scientist, philosopher, and mercenary soldier René Descartes (1596 - 1650). In part out of concern to be consistent with religious doctrine, he presented a dualistic view of human mental activity. We will examine this view more fully later in this book. For now, we can describe Cartesian Dualism as the view according to which people have a dual, or two-part, nature: a purely physical part, the body, and a purely mental part, the nonphysical soul, or mind. Descartes held that mind and body interact at a precise spot within the brain (the pineal gland). But he was quite clear on one crucial matter: mental function does not take place in the brain; it takes place instead in the soul or mind and transmits its effects through the brain. On this view, the brain is nothing more than a sophisticated organic transceiver for the mind. Mind, Descartes held, is unitary: you don't feel love with one part of it, process visual sensations with another part of it, and make decisions with a third. Mind is not a complex physical object and has no parts; whatever it does, it does as a whole, as one undivided thing. Descartes thus took a negative view of what might be called the "hypothesis of localization of mental function", and he took a stand against holding the brain to be the locus of mental activity.

In modern times, the contrary anti-dualistic position was first argued for by the pioneering phrenologists, the Viennese neuroanatomists Franz Josef Gall (1758 - 1828) and Johann Casper Spurzheim (1776 - 1832), Gall's disciple. They opposed Descartes on two scores: (i) they believed that the brain is the organ of mental function, and no mere transceiver; and (ii) they believed that certain parts of the brain were responsible for particular mental functions, including higher mental functions, like love or religious sentiment. They were thus early champions of the hypothesis of localization of mental function. Both Gall and Spurzheim were accomplished neuroanatomists, with a number of important discoveries to their credit. When they embraced phrenology, they left their anatomical researches far behind.

Phrenology seems to have begun with Gall's hypothesis that an enlarged memory center in the brain, which center he took to be behind the eyes, could cause the eyes to protrude. Generalizing on this rather modest initial hypothesis, Gall and Spurzheim identified 27 regions on the skull associated with particular mental functions. A bump in the region signified increased capacity for that function; a depression, or pit, signified a decreased capacity. For example, the associated the region just below and behind the ears with Amativeness - tendency towards romantic love. But with the regions of Destructiveness and Combativeness so nearby, an expert's eye may be needed for any judgments about personality. (Every time I talk about this subject, about 20% of the people in the audience begin checking behind their ears. What on earth do they expect to discover? Does a bump in all three regions excuse their appetites for kinky sex?) Further refinements of phrenology led to a larger number of regional subdivisions, over 80 at one time. Gall and Spurzheim sought to gather data to support their hypotheses and examined hundreds of skulls of both human and animals, never once finding any refutation of their views.

Phrenology had plenty of opponents among other scientists of the era; the most effective among them was Pierre Flourens (1794 - 1867), himself a Cartesian. But phrenology also had plenty of adherents among medical researchers and the educated public. At the height of its popularity in this country, during the mid-1800s, it was a widely accepted theory of how the mind worked. It had all the social trappings of science: the respect of scientists and of educated lay people; training programs; application in the care of the diseased and the deviant; a significant economic role; even its own learned journals, thick with technical jargon. People were hired and fired on the basis of phrenological examinations. Some job ads specified prior phrenological certification (much as some employers now require polygraphing). Just as we are nowadays given the results of the President's medical exam, politicians then would make public the results of phrenological examinations to help show their suitability for public office. Since insanity could be seen as a result of innate malfunction rather than divine curse or moral depravity, attitudes toward the insane took a turn for the better and conditions at some asylums improved; similar benefits accrued to the prison inmates of the day, with great rejoicing when Sing Sing became a "phrenologically conducted institution," Among phrenology's more eloquent adherents were Horace Mann, Walt Whitman, and Edgar Allan Poe.

...the fact remains that, for roughly thirty years, this patently wrong idea made a tremendous impression on the nation. To understand why, it is necessary to realize that, in a sense, phrenology was filling a vacuum. When it appeared, there simply were no real theories of how the human mind worked. Although based on false premises, phrenology was so systematic that it gave the illusion of true understanding. ... Phrenology encouraged people to believe that the human mind could be studied scientifically, that the mentally insane could be treated rationally, and that science could help run the prisons and the schools. Though not science itself, phrenology prepared the ground for the day when true science would tackle these ventures. (MJ Martin)

Gall had stumbled on a theory of brain function that was to prove of the greatest significance. But though pioneering the concept of ... localization, he had clearly done so for the wrong reasons. [As Edwin Boring wrote,] "The theory of Gall and Spurzheim is ... an instance of a theory which, while essentially wrong, was just enough right to further scientific thought." Phrenology helped to move ideas concerning the mind "away from the concept of the unsubstantial Cartesian soul and to the concept of the more material nerve function," and in doing so, "was wrong only in detail and in respect of the enthusiasm of its supporters." (Clarke and Dewhurst)

... By placing man firmly in nature Gall "rescued the problem of mental functions from Metaphysics, and made it one of Biology. In his vision of Psychology as a branch of Biology, subject therefore to all biological laws, and to be pursued by biological methods, he may be said to have given the science its basis" (Lewes quoted by Young)

It's also interesting that Flourens's supposed experimental refutation of Gall's and Spurzheim's guiding hypothesis of localization of brain function was badly flawed. How would you show that the human brain is unnecessary for mental activity? Using human subjects was not feasible, so Flourens settled for what he regarded as a close second best: he cut the brains of chickens by about 90% and observed them running about ("like chickens with their heads cut off"). (This, by the way, is the source of the oft-repeated remark that we human beings use only about 10% of our brain capacity. Unless you think that you're a chicken-head, you have no reason to accept that remark.) It took many more decades of research to put the hypothesis on firmer ground. It is still the subject of active research and is a guiding influence in hypothesis formation in neuroscience.

Is the comparison with which we began a just one? Were the effects of phrenology on the development of science incidental and largely independent of its content? This brief history makes it clear that the answer is "no." By opposing the Cartesian views in some detail, phrenology helped to advance a science of the mind.

Is Phrenology Pseudoscience?

Some writers describe phrenology as prescientific, or as false science. The suggestion is that, like astrology, it may have given science a needed push in the right direction, but without itself being science. On what principled basis might phrenology be dismissed as pseudoscience?

Although the phrenologists did not pretend to know how the various regions of the brain worked to produce their hypothesized capacities, the absence of any knowledge of the physical mechanism was given little or no notice until the hypothesis of localization of function was championed. This third point is especially important because it reminds us that the search for new information won't even begin until there is a hypothesis to prompt and guide it. Science does not proceed by blindly going out and looking for new facts, by randomly doing experiments. The Cartesian conception of mental function made research into many mental functions virtually pointless. When phrenology recommended a new and detailed conception, particular experiments were then called for to either confirm or refute the hypotheses suggested by the new conception. So a key role for any scientific theory is to highlight ignorance.

It's been a long time since astrology has been taken seriously by good minds. But phrenology was admired by some of our grandparents' grandparents - not so long ago. It provides a useful test case for two popular gatekeeping criteria.

We can all agree that the various branches of science have extremely complex and interesting social roles in contemporary society. In addition to all the rites and rituals required of those who seek undergraduate and graduate degrees, postdoctoral fellowships, and other sorts of advancement in academia or industry, there are many professional societies, editorial boards for book and periodicals publishing with a system of peer review, advisory boards convened by government and business... The web of power relationships is important and intricate. One of the main purposes of graduate school in science is to teach the student how to get grant money - and if you think that's a joke, try managing a career in science without the requisite political skills and knowledge.

Some sociologists have suggested that science not only has, but is defined by, its distinctive social role. (One influential argument for this view is based on the view that science is "socially constructed," in the sense that it is, and is not just defined by, a social role.) If this approach is to classify phrenology as its critics believe it should be, then

Phrenology is a pseudoscience because it lacks the social role of a true science.

But this is both unfair to phrenology and a poor way to distinguish science from pseudoscience. In the early nineteenth century, phrenology's social role was more like that of twentieth-century physics than was the social role of early nineteenth-century physics. Social roles take time to grow, and any relatively new branch of science will likely not have had sufficient time to establish the web of social and political relationships that we associate with entrenched science.

The main problem with the social-role definition of science is that it has no connection to the sorts of cognitive standards that ought to be in the forefront of debates about pseudoscience. We can readily imagine a crackpot multibillionaire spending part of his fortune to secure for his lunatic views a social role like that of established branches of science. Nor is money necessary. All that's really needed is access to political power. Lysenko managed to persuade Stalin that evolutionary theory was anti-Marxist and anti-Leninist. Lysenkoism held that acquired characteristics could be inherited by the offspring of those who acquired them, so Soviet citizens 'improved' under Stalin's regime would be 'scientifically' assured that their children would inherit those improvements. Those biologists who disagreed with Lysenko were dealt with very effectively, by being put to death, for example, and Soviet biology was set back many decades relative to the rest of biology. So much for the social-role definition.

It's clear from our discussion of criticisms of astrology that being based somehow on observation, or being testable, is not enough to make a theory scientific; the theory must have other characteristics, as well. Just as a good person is known by her virtues, so is a good theory thus known. While there isn't complete agreement on what the theory-virtues are, there is substantial agreement. I'll mention five characteristics that everyone agrees belong on the list.

The most obvious virtue is internal consistency. A theory is no good if it says, for example, about one and the same event that it will and that it will not occur at a given time. No acceptable theory contradicts itself. If a theory is sufficiently complex, then assuring its internal consistency can require great skill.

Most of us have some beliefs that are not well-supported by evidence or reasoned out with great care. Fortunately, most of us have some beliefs that are well-supported by evidence carefully reasoned out, and these beliefs are worth conserving. If a theory comes along that conflicts with such worthwhile beliefs, then, all other things being equal, the theory's in trouble. So conservatism, understood as consistency with previously held, well-justified beliefs, is another virtue for theories.

One way of taking the measure of a theory's explanatory power is to find out how general it is in its intended domain. Before Newtonian mechanics came along, there was serious doubt about whether the same set of natural laws governed both Earthly and celestial objects. Newton was able to show how one set of laws could explain both, and this theory thus enjoyed a great triumph of generality. On a less grand scale, we would rather have a general theory of conductivity of all materials under all circumstances than a theory that covered just long, thin pieces of copper wire at room temperature - useful though the latter would be. Other things being equal, the more generality a theory has, the better.

It's not always wise to maximize conservatism, however. By giving up on previously well-justified beliefs, we can sometimes gain a great deal in generality. If this happens in a big way, we call it a 'scientific revolution'. When Einstein proposed special relativity, it was immediately accepted by physicists despite its inconsistency with Newtonian mechanics because relativity theory was so much more general than the latter. They knew they were getting a great deal, so they readily accepted the trade-off between conservatism and generality.

Precision is a widely recognized virtue of theories. Colleges and universities do a lot to train students in assessing the numerical or quantitative precision of theories, and that's very important. But there's another kind of precision that's at least as important: definitional or qualitative precision. The fundamental concepts that a theory offers us as tools for explanation should have well-defined boundaries and clear conditions of application. (See "The Meaning of 'Life'" for more on analytical definition.) The more precise a theory is, the more strongly it will tend to be confirmed or disconfirmed by the evidence.

Many add simplicity to this list of virtues. I'm not sure what simplicity is. Is it a feature of the theories themselves? Some theories that seem very complex to me seem quite simple to the relevant experts. Is simplicity then relative to educational background and brains? I do know that some very simple characterizations of simplicity are too simple to work. For example:

The simplest theory is one that says there are the fewest different kinds of things.

Despite its vagueness, we can see that this can't be right. Suppose a Theory of Everything 1 said that all matter in the world was made out of just four different kinds of particles, while a Theory of Everything 2 said everything was made out of (just) eight different kinds of particles. Is Theory 1 necessarily simpler than Theory 2? Of course not. The laws and relationships that Theory 1 postulates may be far more complex than those postulated by Theory 2, and the net result may be greater overall simplicity for the latter. We need a general account of the simplicity of laws or relations before we can even get this approach to simplicity working. I conclude that simplicity is very complex, and I'll leave it at that.

Just to have a short expression for all this, let's give the label "systematic" to the combination of these virtues of theories. So, we can now say, the more systematic a theory is, the better. And a theory that is utterly nonsystematic is worthless.

I gave you a 'rule of thumb' test for assessing progress in science (in "Astrology"). I'll give you a similarly rough test for systematicity. To determine how systematic a theory or part of science is, gather up all the relevant texts and weigh them - the lighter they are, the better. This test works pretty well because highly unified, systematic theories can usually be boiled down to a few basic principles that can be clearly and briefly stated (often using mathematical formulae), and the rest of the text can be devoted to illustrating their applications via instructive examples. Even (or especially) an advanced text on classical (Newtonian) mechanics in physics will be relatively short and won't weigh much. Things are different in medicine, which deals with the most complex systems in the known universe; there isn't as much in the way of systematic theories in medicine, so medical texts tend to provide a multitude of different ways to categorize huge numbers of facts for different medical purposes, and this makes them very large and heavy. There is, for example, one textbook on eyes that's fifteen thick, oversized volumes long. (Ironically, it's called a "system.")

If we're to deploy these ideas against phrenology, we'd have to argue that

Phrenology is a pseudoscience because it's not systematic; it's not the right kind of system of hypotheses.

But phrenology was highly systematic, in fact, and also quite specific in its predictions. The basic text of phrenology weighs just a few pounds. It may be better off in this respect than some of the cookbook-systems accepted by modern doctors. While phrenology was nonconservative in its inconsistency with dominant Cartesian views, it offered in return a more general account of nervous system functioning, which seems a fair trade-off between conservatism and generality.

The main problem for us is that our picture of science does not allow us to use systematicity in assessing theories because while it makes perfectly good sense to say that one theory is more (or less) systematic than another, there is no rational basis, with this sort of standard, for drawing a sharp line between starters and nonstarters in the race for truth. In the Introduction, however, we agreed provisionally to adopt the common view that a theory is sharply defined as either a starter or a nonstarter, where there's no middle ground. Given the inherent plausibility of assessing theories by systematicity, this is our first clear signal that, perhaps, something is seriously wrong with our provisional picture of science. We will soon find that this is so.

In some ways, then, phrenology seems clearly superior to astrology. One might say that, at worst, it consists of a tangled weave of science and pseudoscience. It is apparently quite difficult to separate the threads.

Parapsychology

Parapsychology is a relatively young branch of inquiry. It dates from the late nineteenth century with the founding of the British Society for Psychical Research, among whose members were some famous philosophers, psychologists, and scientists, including the American William James, as well as Arthur Conan Doyle, the creator of Sherlock Holmes.

The first problem we meet is a rather basic one: What is parapsychology? The term itself means only "outside of, but related to, psychology"; that can't be a good definition here, since biology would then be counted as parapsychology. To say it is the study of paranormal phenomena doesn't help much either, unless we're told what "paranormal" means. If paranormal phenomena are defined as those that do not have any discoverable natural causes or scientific explanation, then that immediately disqualifies parapsychology as nonscientific and makes further scientific investigation pointless. It'd be cheating to try to settle the debate by such stipulative definition. Often there is an anti-materialistic bias and a strong sympathy for a dualistic view of mental phenomena among parapsychologists, but this is a just a matter of personal bias and has no business being assumed as definitive of parapsychological investigation. There are other ways that one might characterize the boundaries of the concepts "parapsychology" and "paranormal," but they have their problems, too. Perhaps we need look no further. The trouble in defining parapsychology suggests an easy way to dismiss it as pseudoscience, since, as we've seen, precision in definition is a virtue:

Parapsychology is a pseudoscience because it and its fundamental concept, paranormal phenomenon, lack any clear definition; sciences always have clearly defined fundamental concepts.

Like most easy ways of dealing with something, this one is wrong. In many well-developed branches of science there is profound controversy and unclarity about fundamental concepts. I have already alluded to the dispute in biology over the concept of "living thing." The problem is not just how to classify viruses. The successes of molecular biology are remarkable, but do they support a chemical definition of life, or an information-theoretic definition that allows for artificial life? Also within biology, there is a very active debate, with a direct influence on the choice of experiments and the distribution of grant money, concerning the proper definition of the notion of species, so important to evolutionary biology. In medicine, there is no more important distinction that between being alive and being dead; the last thing you want your doctor to be fuzzy about is that distinction. But it is bedeviled by hard cases, and despite the moral urgency attached to drawing the line, no hard and fast distinction seems on the horizon. The situation is so bad that some state legislatures have stipulated a legal definition of death (typically some sort of 'brain death' criterion), but, of course, one doesn't solve such conceptual problems by legislative stipulation. In developing sciences, the fundamental concepts may be ill-defined or even unknown. It often takes a while, say, 100 years, for it to become apparent how best to organize a new field of inquiry. In the sixteenth and seventeenth centuries, when modern physics was getting its start, there was just such debate concerning force and momentum. While precision in definition is certainly highly desirable, it is often the end result of a great deal of experimental and theoretical investigation. One of the most difficult tasks in science is figuring out which concepts are needed to explain the phenomena we discover. Nevertheless, we don't allow complete chaos to reign when we grant that there is a field of inquiry developing. But parapsychology is not completely chaotic either. There are certain classes of phenomena which it seeks to study (either by proving that there are such phenomena or by proving that there are none): ESP of various sorts (clairvoyance, precognition), telekinesis, reincarnation, communication with the dead, dowsing, psychometry, and so on. Although it may be more chaotic than most familiar examples of science, it can't on that ground alone be dismissed. We must, after all, be careful not to cut off new inquiry too quickly.

In 1987, a psychologist named David Marks published a helpful review of parapsychology in one of the world's leading science journals, Nature. He makes an astonishing and potentially disturbing observation about parapsychology: that there are no theories to account for paranormal phenomena. But as we've already seen in the case of astrology, the absence of a known underlying physical mechanism is no reason to dismiss something as pseudoscience. There is, however, another criticism lurking in the neighborhood, and it may seem more promising:

Parapsychology is a pseudoscience because paranormal phenomena are known to be physically impossible.

To take a simpler case, suppose that Senator Porkbarrel proposed funding an Institute for the Advanced Study of Round Squares. He wouldn't get very far because round squares are impossible, and we can prove that. One problem with this criticism is that it isn't so clear that paranormal phenomena are physically impossible. (Remember that the belief of some parapsychologists in purely spiritual, nonphysical media is just that: their belief, not a fundamental principle of parapsychology.) There might, for example, be some hitherto unsuspected, purely physical mechanism permitting the transmission of information from one mind to another without going through the usual channels. What's often at issue in such a debate is just what is and is not physically possible, possible, that is, according to science. Suppose, however, that parapsychology established in some way, experimental, theoretical, or both, that paranormal phenomena were physically impossible. That in itself would be a scientific achievement. Impossibility arguments and proofs are quite common and valuable in all branches of science since they help to define the extant theories and to constrain the range of possibilities to investigate. Although parapsychology would thereby put itself out of business, that's nothing against it; we all hope that someday medicine will put itself out of business, too.

Perhaps there's no point in looking for such underlying mechanisms if there's no reason to believe that such extrasensory perception of one mind by another ever actually occurs. (Remember that what we're looking for here is a criterion that will allow us to send the unqualified packing, not a principle that will tell us in advance who'll win the race for truth.) If the objection is to be relevant in this case, it must be because it's based on a suspicion that the methods of parapsychology are not of the right kind to yield the relevant information about the actuality of ESP. And there is, after all, much talk among scientists and others of the scientific method. Perhaps then

Parapsychology is a pseudoscience because it does not employ the scientific method.

This criterion is pretty empty unless we've got some independent understanding of what the scientific method is. I'm skeptical that there is such a thing. Try this 'experiment': find basic college-level texts in each major branch of science and look through them. Do you get an impression of one method, common to all branches? On the contrary, the overwhelming impression is of enormous diversity - of methods, among other things. And this impression would only be reinforced by a wider survey of more advanced materials. There are many, many methods in science. Nevertheless, some sorts of reasoning do seem especially important throughout science. The kind of reasoning taught in statistics and lab courses about designing of experiments, estimating precision, and estimating probability and degrees of confidence are part and parcel of scientific method, as are the principles of deductive logic taught in symbolic logic courses. If parapsychology systematically ignores all of that, then it might justly be sent home before the race. And if it systematically tries to excuse every apparent failure of every relevant statistical tests, that would tend to show that it had no real interest in sticking to the standards set by statistical reasoning.

However, if anything is clear about parapsychology, it is that it strives to employ the statistical techniques common to the conduct of the rest of experimental science. Some, even many, of its practitioners make mistakes in the application of statistical techniques, but parapsychology is hardly unique in that respect: much of modern statistical theory was developed to serve as sound techniques for assessment of agricultural experiments which hadn't been so well-managed before. The author of one standard introductory text on probability theory gives examples drawn from respectable scientific journals of misapplied statistical technique. In fact, plenty of published parapsychological research exemplifies very high standards of statistical reasoning; and in those many cases where the highest standards were not observed the investigator may nevertheless have been trying hard to do well. The most famous modern parapsychologist, J. B. Rhine, who worked at Duke University for many years, often stressed the importance of proper statistical design and analysis of experiments.

To recall a previously discussed and unsuccessful criterion, parapsychology has a social role very much like that of older, more established sciences: its investigators have attained well-paid university posts, there are research institutes devoted to it, and parapsychologists publish technical articles in their own journals and in some of the best psychology journals. Even their orders for equipment are much the same as those of other lab scientists: computers, various measuring devices, special shielded chambers, and so on.

So despite its relative conceptual disarray, the doubts of some about the possibility of paranormal phenomena, and the statistical mistakes of some of its investigators, parapsychology seems especially difficult to rule out, on principled grounds, as pseudoscience.

As before, none of our discussion tends in the least to show that the provocative claims made by parapsychologists are true. A careful look at the data shows that despite many years of trying, not a single properly performed experiment has shown the existence of any paranormal phenomena. Why, then, is belief in such phenomena so widespread, given that it is scientifically unsupported? This isn't exactly on topic, but it's such an interesting question about human irrationality that I want to say just a bit about it.

How many of you have had this experience: you pick up the phone to call your best friend (spouse, mother, etc.), and there, at the other end of the line, is your friend waiting to talk with you - the phone's not even had a chance to ring! What an amazing coincidence! Why, the only possible explanation is extrasensory contact, mind to mind, without benefit of telephone wires! Phooey. Given how often people talk to one another on the phone and the tendency of human schedules to synchronize, this experience is not that unlikely. Amazing-seeming coincidences are often cited as evidence for various paranormal phenomena. But amazing-seeming coincidences are far more common than most of us think - that, of course, is why they seem amazing when they occur, and this fact is exploited by pretenders to psychic power. There is an interesting body of psychological research on how bad most people are at estimating probabilities, even after having received extensive training and done well on standard tests. Some researchers have even been driven to hypothesize that being bad at statistics might have evolutionary survival value. I'm not sure we need to go quite that far, but there's no denying that most of us do a poor job in this arena. To give two other simple examples: The likelihood of getting five heads for five fair coins flipped at once is about three percent; but the likelihood of the same outcome in a run of 100 flips is about ninety-six percent, far higher than most would estimate. Then there is the suprising Common Birthday phenomenon, which can be used by pretenders to psychic powers. In a randomly selected group of just 200 the likelihood that two or more people will have the same birthday is very high, about 1 - (1/1055), which is awfully close to dead certain. Not only do our inadequacies in estimating likelihoods make us more credulous than we ought to be, they also interfere with rational assessment of risk and so make public policy-setting to deal with risks far more difficult.

We have examined three allegedly clear examples of pseudoscience. They form a sort of progression. Astrology had an effect on the development of a true science - astronomy - but its connection was not one of content: no specifically astrological principles remain part of astronomy. Phrenology had not only an important effect on the development of modern neuropsychology, but it actually contributed some content: (an early version of) a central hypothesis of modern brain science, the hypothesis of localization of brain function. Nevertheless, phrenology was very badly flawed in its methods. Parapsychology may not have an important contribution to make to the way science views the mind, but its methods are often those of true science. We may not care deeply about how any of these three are classified, as nonscience or bad science; either way, they don't win the race - although the prevalence of belief in ESP suggests that many of you do care about the fate of parapsychology. We turn next to an example that has been the focus of an intense and emotionally charged controversy, one that has already has had an effect on how children are educated, and on the larger issue of the proper role of education in our society. I refer, of course, to Scientific Creationism. Many of its opponents, some of whom have testified to their views in court, claim that it is pseudoscience - a cover for a religious and political agenda that has no place in the public schools. (Some of its opponents even contend that it doesn't belong in private schools or churches - they want it to go away altogether.) We'll next take a look at whether their charge of pseudoscience stands up under scrutiny. And we'll take a close look at how Scientific Creationism itself fares when judged by the scientific standards its proponents claim as their own.

Scientific Creationism in the Courts

Scientific Creationism is one of the most controversial and highly visible alleged examples of pseudoscience. I've found that there's a lot of confusion about exactly what's at issue in the public debates. Many who rely on the brief reports in newspapers and weekly news magazines come away with the impression that the key question is, Should religion be treated with respect in the public schools? Many more seem to believe that Scientific Creationism is simply the view that God, as conceived of in the Judaeo-Christian tradition, created and designed the universe with all its natural laws (maybe by causing the Big Bang). But neither of those perceptions is correct, and you can't figure out what's going on without getting beyond the usual news reports. We can move in the right direction by first considering one of the Scientific Creationists' political successes and the court case it engendered.

In 1981, some Scientific Creationists were able to persuade the Arkansas state legislature to pass a law that required the teaching of Scientific Creationism in public school science courses alongside evolutionary theory. Soon after the law (Act 590, aka "The Creation Science Law") was passed, a suit was filed against the State of Arkansas in federal court (McLean v Arkansas), alleging that the law violated the constitutional doctrine of separation of church and state. The ensuing trial took many weeks and involved the testimony of many expert witnesses. After considering all the testimony, Judge William Overton issued a long, detailed opinion in which he explained his ruling against the State of Arkansas. Among several different sorts of reasons for his ruling was his finding that Scientific Creationism is not science but religion masquerading as science. In coming to the latter conclusion, Judge Overton was heavily influenced by the testimony of two witnesses: Langdon Gilkey, a Protestant theologian at the University of Chicago, and Michael Ruse, a historian and philosopher of biology then at the University of Guelph, Canada. Let's see what they had to say.

"At the Interface of Inquiry and Belief," an article that Gilkey wrote to present the essentials of his testimony, very helpfully summarizes the main precepts of Scientific Creationism as they were specified in the Arkansas law, under the guidance of authoritative Scientific Creationists.

Although the [Arkansas] law did not mention either God or the Book of Genesis, it did list as the elements of the creation science model: the sudden creation of all things out of nothing; creation of separate and distinct "kinds" at the beginning; the catastrophic interpretation of the Earth's history [i.e., the Noachian flood]; and the "recent" beginning of the universe. Each of these elements requires for its intelligibility the notion of a supra-natural creative act. (67)

Before considering Gilkey's reasons for thinking Scientific Creationism pseudoscientific, let's look a bit more closely at its four essentials as specified here. We're offered an explanation of the origin and order of the universe and of life on Earth. The theory says first that the universe was created suddenly out of nothing. This kind of creation is not the kind that we have in mind when we talk, for example, of an artist's creating a piece of sculpture. There, preexisting material is given a new form. The creation of the universe is unlike that, according to Scientific Creationism, since there was no preexisting material to which form was then given. Second, the theory says, all the kinds of living things that there ever have been on Earth were present, together, at or near the Earth's beginning, and furthermore, there has been no significant change in the kinds of living things since then (except that some have 'emptied out' through extinction). So the creator of the universe conceived and implemented an 'organization chart' for life at the outset and has not changed its basic structure since then. This, of course, implies that dinosaurs, bacteria, plants, jelly fish, rabbits, dodos, apes, and human beings all coexisted on Earth since the beginning, though the dinosaurs and dodos are no longer around. It also implies that genuinely new kinds of organisms did not develop during Earth's history. Third, the theory says that the fossil record is stratified in the way we now find it because a great cataclysm killed off many living things and, when flood waters receded, their remains were deposited in layers. Finally, although there is some disagreement among the relevant Scientific Creationist authorities, the theory is committed to an estimate for the age of the universe and Earth of less than 20,000 years.

It is very important to keep in mind that it is these four essentials that define the core of Scientific Creationism. So the theory is far more specific than the assertion that God created and designed the universe. (You're welcome to continue to use the term "creationism," as many do, to express the less specific assertion, but please keep it in mind that I'll be using "Scientific Creationism" to mean any view with these four essentials as its core.) Of course, any explanation of life in the universe will have to be far more specific than "God created and designed the universe" if it's to do any real explaining at all, a point we'll return to later. It's equally clear that a good explanation will need to provide far more detail than is offered in these four essentials. There must be more to Scientific Creationism than its bare essentials if it is to compete with modern evolutionary theory, and, not surprisingly, there is a lot more to be said about it, as we'll also see later.

Why does Gilkey think that this theory (or theory-essence) is pseudoscientific? Here are some of his reasons:

The creation-science "model" is, therefore, not an example of science at all: it involves a supra-natural cause, transcendent to the system of finite causes; it explains in terms of purposes and intentions; and it cites a transcendent, unique, and unrepeatable - even in principle, uncontrollable - action. (68)

Creationists fail to distinguish the question of ultimate origins (Where did it all come from?) from the quite different question of proximate origins (How did A arise from B, if it did?). ... Scientific explanations of proximate origins are confined to using finite causes as principles of explanation and thus leave quite open the question of God. (68-9)

The Arkansas law, therefore, is religious not because it refers explicitly to a doctrine or appeals to scripture but because the notion of the agency of a supra-natural being is essential to each of the constitutive elements of the creationist model ... . (69)

Gilkey even says that it is a rule of scientific method that "no supra-natural causes may be included in a theory" (68). So it looks like Gilkey's fundamental criticism is:

Scientific Creationism is pseudoscience because it essentially involves supernatural causes in its explanations.

There is one distinction here that is doing the hard work: the difference between natural causes, on the one hand, and supernatural causes, on the other. So we're entitled to press for clarity in the meaning of "supernatural." Literally, the word means "above, or beyond, what is natural." Unfortunately, the word "natural" has been stretched out of shape through abuse by advertisers. We are exhorted to buy a diverse array of products because they are somehow 'natural': there are natural breakfast cereals, natural lawn care products, natural shoes. (Of course, the advertisers would prefer that you forget about all the bad things that are natural. No one ever says, "Buy new, improved Bubonic Plague Crunchies - they're as natural as disease!") Here, however, the most natural way to understand "natural" is as the adjective form of "nature," conceived of as the proper subject of scientific studies; so natural is short for "whatever is the proper domain of science." But if we plug in the relevant definition, we get

Scientific Creationism is pseudoscience because it essentially involves causes that are outside the proper domain of science

or, more simply:

Scientific Creationism is pseudoscience because it's not science.

a criticism of truly stupefying uselessness. Although I hesitate to attribute this to Gilkey, I have some reason to do so. I was in the audience at a talk Gilkey gave around the time he was testifying in the Arkansas trial. The talk included the remarks I've quoted. During the question period, one of my best students, James Holman, asked Gilkey what he meant by "supernatural." I was very proud of Jim - he had, I thought, zeroed in on the crucial point. How did Gilkey respond? He replied that it was perfectly obvious, and so known to intelligent and educated people, what the distinction between natural and supernatural was; next question, please. But if it was so obvious, why didn't he just say what it was, and enlighten my student (and the rest of the unintelligent or uneducated people in the audience)? It's hard to resist the suspicion that he didn't have a good answer. There are, I think, just two other meanings that are faithful to what Gilkey said, and neither yields a good criticism.

In one of his remarks, Gilkey seems to imply that any explanation of the ultimate origins of the universe is bound to transcend the boundaries of science by invoking supernatural causes. Maybe he means to suggest that "supernatural" means "any attempt to explain the ultimate origins of the universe." If that is what he means, then his criticism is in trouble, because there is a very old and recently quite successful branch of physics - cosmology - that tries to explain the ultimate origins of the universe. In a justly well-known popularization entitled The First Three Minutes, Nobel Prize-winning physicist Steven Weinberg describes the work of contemporary cosmologists as they attempt to understand why the Big Bang itself occurred. More recently, Stephen Hawking and Roger Penrose have presented their views on these matters for a nonscientist audience. No physicist is arrogant enough to think that she has all the answers yet, and, like a lot of other theories in the history of physics, the Big Bang theory might turn out to be wrong, but that's beside the point. The point is that the pursuit of such questions of ultimate origins is already a part of science.

Can we save Gilkey's criticism in another way? He does also suggest that the super-natural may involve explanation in term of purposes and intentions, and "transcendent, unique, unrepeatable, in-principle-uncontrollable, action." So maybe "supernatural" means "any attempt to explain in terms of a purposive, intentional action (that is unique, etc.)." But why should adverting to such causes make an explanation or theory unscientific? Biology is full of explanations that talk of the goals, purposes and functions of living things and their parts. Social sciences - e.g., psychology - need to talk of these things simply to state, no less to explain, the relevant facts about human minds. Nor should it matter that the purposes in questions are somehow extraordinary. Biologists and psychologists have shown an interest in abnormal - subnormal and supernormal - functioning both for its own sake and as a way of defining the range of normal functioning. At the very least, we're owed a good argument as to why a psychology of superhuman minds is beyond the reach of any possible science. (Maybe it already exists - maybe it's part of some theology.)

Gilkey is too intelligent and well-educated to charge Scientific Creationism with pseuduoscientific status merely because it is inspired by certain religious views. That would be as bad as dismissing chemistry because of its origins in magic, superstition, or alchemy. And even if the content of Scientific Creationism does overlap with the religious beliefs of some, why would that alone make it pseudoscientific? It wouldn't. It might, for example, still be open to the usual sorts of challenges and tests to which other scientific theories are subject.

I don't think Gilkey has given us a good reason for thinking that Scientific Creationism isn't scientific.

Ruse takes a different approach. He claims that something must have several features - necessary conditions - if it is to be science, and he says what he thinks they are. He then argues that Scientific Creationism lacks all of these features and concludes that it's mere pseudoscience. So he seems to think of science as a rather exclusive club, with very strict membership requirements - if something fails to meet even one of them, it's blackballed. (He also claims that he's not giving necessary conditions, but we won't trouble him about his inconsistency. Besides, his argument clearly requires that the conditions he suggests be necessary.) The form of his argument is therefore:

Ruse's ABCs of Science

If something is science, then it must have A, B, and C.

Scientific Creationism doesn't have A.

Scientific Creationism doesn't have B.

Scientific Creationism doesn't have C.

Therefore, Scientific Creationism is not science.

Logically, this is overkill: the first premise and one of the other premises would yield the conclusion. But, to his credit, Ruse was trying to be thorough and to hit Scientific Creationism at what he saw as its weakest points.

What, according to Ruse, are the ABCs of science? He says that (A) scientific knowledge is guided by natural law, and scientific explanations are based on natural law; (B) scientific explanations are testable and so falsifiable; and (C) scientific theories are tentatively, non-dogmatically held and revisable in response to additional relevant evidence. Scientific Creationism, Ruse says, has none of these three features and so is mere pseudoscience, because its explanations are not guided by natural law; it is not testable and so not falsifiable; and it is dogmatically held and not revisable in the face of new evidence.

Let's look at this attempt to deal a triple blow to Scientific Creationism (which influenced Judge Overton's decision so heavily).

Take (A) first. As many have pointed out, and as Larry Laudan remarks, scientists have long understood the difference between establishing the existence of phenomena and explaining them by natural laws. To give two examples: Darwin established the existence of natural selection about fifty years before the discovery of the laws of heredity which help to explain it; even if there had been no such laws, Darwin's discovery would still have been scientific. The phenomenon of radioactivity was discovered near the turn of the century by a French physicist, Becquerel. It was not until over 30 years later that a partial explanation based on laws was discovered, and it took twice that long for a more nearly complete explanation based on laws. Nevertheless, those who discovered and investigated the various forms of radioactivity during that time were advancing science, and some of them received well-deserved Nobel Prizes for their work. So A is not a requirement for being science.

Next, consider (B), the claim that being testable, and so falsifiable, is a requirement for science. The first thing we need to do is to get clear on why being falsifiable is thought to be necessary. At first hearing, it may sound like a horrible defect rather than a virtue for scientific explanations to have. Notice that what's being required here is not that the explanation be shown false (falsified), but that it have the potential for being shown false (falsifiable). Even a true statement may have that potential. Consider, for example, the statement that you are reading this now. Although it is clearly true, we all know perfectly well what kind of procedure we would have to follow to test it, what kind of evidence would count against it. Perhaps the best way to see the virtue of falsifiability is to look at a case where it is missing, and to see also that something's gone very wrong in that case. So consider the bizarre assertion: "The universe was created 5 minutes ago, complete with (deceptive) memories, fossil records, distribution of light particles throughout, etc." No sane person believes this. But suppose you were challenged to prove that it was false by citing some evidence against it. There really isn't any evidence that you could bring to bear against it because the statement itself dismisses any evidence that seems to count against it as merely deceptive. So it is not falsifiable. Of course, by the same token, there is no possible evidence that could be given in its favor. Hence it is not testable - neither falsifiable nor verifiable. And that, of course, is precisely what is wrong with it: no possible piece of evidence could tend to confirm or to refute it. Despite seeming to take a quite definite stand on how things actually are, it is instead a rather empty hypothesis. Turning things around, we can see that being falsifiable is the least we should expect of a hypothesis. Let's agree with Ruse that falsifiability and testability - some conceivable sort of openness to experimental test - are, at a minimum, to be required of scientific explanations.

[There is yet another qualification that we must add. This requirement, if it is to have any plausibility, must be applied to whole theories, not to the individual statements they may make. Consider, for example, the statement that there are electrons in a particular orbital of an atom­a statement of atomic theory, which includes many other hypotheses and explanations about the structure of atoms, the forces that operate in them, the meanings of the terms in the theory, and so on. Since the meaning of the individual statement's terms is fixed in part by all the other parts of the theory, it is the theory that gets tested, and not just isolated statements of it. None of this is made clear by Ruse, or by Judge Overton. Both talk as if it is the isolated statements of Scientific Creationism that must in and of themselves be falsifiable and testable.]

But even if individual statements are considered, it seems clear that Scientific Creationism meets rather than fails this requirement. It makes lots of falsifiable, testable claims, as its proponents quite rightly insist. For example, there is the claim that no matter on Earth is more than 20,000 years old, and the claim that there has been no change in the kinds of living things since Earth came into existence. Surely, we can think of procedures for testing both of these claims, and many others made by Scientific Creationism. In fact, such procedures have been thought of and used! It may be that the Scientific Creationists themselves have not undertaken to test these claims, but there's no rule that says a theorist must test her own theories; others are allowed to help out, and, as a practical matter, a division of labor between theoreticians and experimentalists is often necessary.

Finally, let's look at (C), the charge that Scientific Creationism is held dogmatically, and not tentatively, by its proponents, and that Scientific Creationism is not open to revision in the face of new evidence. There are at least two reasons that this charge is wrong. First, the psychological attitude of a scientist toward a theory is wholly irrelevant to the theory's status as science. A twentieth-century physicist may be wholly dogmatic about the law of the conservation of energy; that doesn't make the law nonscientific. It might show some flaw in his character or cognitive faculties, but it would not suddenly render thermodynamics pseudoscientific bunk. Similarly, even if Scientific Creationists were utterly dogmatic about Scientific Creationism, that alone would not show that the view is not science. Second, the historical fact is that Scientific Creationists can and do change their minds from time to time. Twentieth-century Scientific Creationists differ from their nineteenth-century counterparts. As Stephen Jay Gould notes, they have modified their views about the amount of variability allowed at the level of species change. And more recently, they have changed their minds about a fossil record that they thought provided support for their view. So they do show some willingness to revise theoretical principles and to reconsider evidence. Perhaps they are less willing than some scientists to do so, but the difference is one of degree, and Ruse's argument allows no room for such subtleties.

Ruse's reasoning was understood and accepted by Judge Overton, and it was the main argument given by the judge for overturning the Arkansas Creation Science law. We have seen that the argument is not a good one. In fact, it's awful. Ruse's charges against Scientific Creationism are either false or irrelevant.

A few years after Arkansas passed its Creation Science Law, Louisiana passed a somewhat similar law. It, too, was challenged in court, but this time, the challenge reached the US Supreme Court, which, following reasoning much like Judge Overton's (and indeed making specific reference to it), found that Scientific Creationism is religion masquerading as science and so has no place in the public school science classroom (Edwards v. Aguillard 1987).

To the extent that Ruse's and Gilkey's criticisms support these judicial decisions, this is cause for great sadness. A badly distorted view of science has been incorporated into our constitutional tradition, and since religion is in part defined by contrast to science, these distortions also affect the way our legal system deals with religion. What an awful mess.

When we discussed astrology, phrenology, and parapsychology, we found no good reason to dismiss them as pseudoscience. But that did not imply that what they had to say was true, or even likely to be true. The same holds for our discussion of Scientific Creationism: the failures of Gilkey's and Ruse's arguments do not in the least tend to show the truth or likelihood of Scientific Creationism. Just because one route (to the conclusion that Scientific Creationism is false or unlikely) is blocked does not mean that all routes to that conclusion are blocked; there may be many other routes open. We should also remember, however, that there are much worse things for a theory to be than merely false; after all, Newtonian mechanics has that defect, and it's still a shining example of scientific theorizing near its best.

Scientific Creationists themselves insist that their view be judged by the same standards on which their supposed chief competitor, the modern theory of evolution, is judged. They also argue that, according to those standards, evolutionary theory itself is seriously deficient. What, according to Scientific Creationists, is wrong with evolutionary theory? Because this question has been dealt with so effectively in the writings on this debate, I'm going to skip over all but one of their criticisms. Although I believe that it's been shown that Creationist criticisms fail to kill or even injure evolutionary theory, it doesn't really matter whether I'm right or wrong about this. Whether Creationists have failed or succeeded in their criticisms of evolutionary theory tells us nothing about how Scientific Creationism, the theory itself, fares when judged on its own merits, according to the proper criteria for evaluating explanations. We owe it to ourselves as well as the Scientific Creationists to judge their theory as they insist.

Seeking Scientific Creationism

What are those criteria? We've been looking for them, so far without notable success. What's shaped our inquiry so far is the hope that there is a simple, clear, sharply defined line between starters and nonstarters in the race for truth. It's high time that we reconsidered our hope since, it seems, it's gotten us nowhere worth staying.

Our working model of successful theories has led some to embrace falsifiability as the essential mark of the scientific. If a theory has any observational consequences at all, then it should be possible to determine whether it is false by making the appropriate observations. If, on the other hand, a theory has no observational consequences at all, it will be impossible to test observationally, and thus incapable of predictive success or predictive failure.

Creationists have sometimes charged that, unlike the rest of science, evolutionary theory is unfalsifiable and so not science. At least one historian has argued that Creationists operate with an outdated conception of science, one that was current during the nineteenth century, when their position was first enunciated in this country. Whether this claim is historically correct, it is clear now - and has been clear to philosophers of science for at least thirty years, and perhaps three hundred years - that the naive view of falsifiability and the 'predictive success' model of theory assessment on which it is based are both fundamentally wrong. They do not give a correct idea of how science has ever worked. This can be shown by considering one of the greatest genuine successes of Newtonian mechanics, from which we can also see how that insight comes into play.

The Discovery of Neptune

Newtonian celestial mechanics is one of the star achievements in the history of science. It was used to compute the planets' orbits to extraordinary accuracy, and it is still used by NASA in determining the trajectories of rockets. As predictive successes go, it was a great one. By 1830, it was quite clear that the observations of Uranus's path diverged from the one predicted by Newtonian mechanics - it wobbled. So something had to give. Astronomers were faced with three main options: (a) give up on Newtonian mechanics altogether; (b) suppose that there were special nongravitational forces operating on Uranus alone; (c) suppose that there was an unobserved mass exerting a perturbing gravitational force on Uranus. No one seriously considered taking the first option - but if predictive success were really all that mattered, then we'd have expected (a) to be actively considered. The fact that it was not is a clear signal to us that Newtonian mechanics had clearly perceived and well-appreciated virtues other than predictive success. The third option was independently suggested in 1845 by two astronomers (Adams and Leverrier). They actually computed what the orbit of a perturbing planet would have to be to explain the deviations of Uranus from the predicted path. Astronomers looked for the perturbing planet, and, in 1846, Neptune was discovered. (A similar procedure was followed later and led to the discovery, in 1930, of Pluto.)

Although scientists saw that Newtonian celestial mechanics was worth saving, it was not just because they thought it was a predictively successful theory. It was because it was part of a larger theory that gave a highly unified explanation of much of what goes on in the physical world. There are two aspects of this moral to the story. The first aspect has to do with unification: Newtonian physics had a single small set of principles and strategies to use in solving a very broad range of problems and answering a very broad range of questions about the physical world; it had the power of generality that we have mentioned before (in our discussion of phrenology's alleged lack of systematicity). The second aspect of this moral has to do with explanation. Although we do want predictive success from scientific theories, we want more; that is, we want to know more than what will happen, we also want to know why it will happen (or why it has happened, or why it is happening - explanation is not restricted to the future; neither, by the way, is prediction). There have been many times in the history of science when perfectly regular connections have been observed and summarized in what are called "phenomenological descriptions"; but we are almost never satisfied by mere descriptions of a regularity or pattern. We also want to know what the underlying reason is for the occurrence of that particular pattern. To take one example from the recent history of science: atomic spectra were observed around the turn of the century. When atoms were bombarded with electrons or photons of certain energies, they would emit radiation in highly regular series, or spectra, and, contrary to all contemporary expectations, the spectra were full of gaps instead of being continuous. But being able to predict that they would emit certain patterns of radiation was not enough: physicists wanted to know why there were gaps, what the reason was for their occurrence. That was what drove the search for a theory of atomic spectra. To be sure, having that theory allows additional predictions to be made, which is a desirable consequence; but the desire for explanation remains. From current physics, we have another example: there are just four known forces in nature, gravitational, electromagnetic, strong nuclear, and weak nuclear. Ever since it's been thought that these are all the forces, physicists have been hard at work looking for a deeper explanation of how they are related to one another, how they might be different manifestations of a single, underlying reality. Grand Unified Theories (GUTs) promise a unified understanding of all but the gravitational force. Totally Unified Theories (TUTs) promise such understanding of all four forces in one unified scheme. One of the hottest contenders for a TUT - Superstring theory - says that space has nine dimensions, six of which you haven't noticed because they are curled up like tiny six-dimensional spheres attached to each point in three-dimensional walking-around space. That shows you how far scientists will go to get a wholly unified explanation.

The best scientific theories suggest new avenues of research, new questions to ask, and new ways to look for answers. They have what Kitcher calls "fecundity." Whatever its flaws may have been - and there were plenty - phrenology did force neuropsychologists to give serious consideration to a new hypothesis: localization of brain function. With the traditional Cartesian view in place, investigation of 'higher' mental functions seemed pointless. It is largely thanks to phrenology that modern neuropsychology enjoys great fecundity. This is not to say that any theory that causes a lot of activity and investigation is a good one. An awful theory can do that. The point is that scientific theories, even very good ones, can be incomplete, and that that can be a good sign, or not necessarily a bad one. (This issue comes up in evaluating evolutionary theory when it is criticized for not giving a complete account of the origin of life on Earth. What drives the criticism is a misguided metaphor: the theory is seen as a skyscraper which must have a firm foundation. But a better metaphor is that of a vast, intricate, but incomplete mosaic or jig-saw puzzle, with many pieces filled in, and known constraints on how the rest will look. Part of the picture that's missing some pieces is the part that tells us how self-replicating molecules were formed in the first place.)

In the discussion of phrenology, we examined the idea that the most systematic theories are the best ones. The six qualities that make an explanation systematic come in degrees, so theories can be more or less good depending on how much of each they have. If we wish, we may reserve the label "pseudoscientific" for those theories that are almost wholly lacking in all of these qualities. But there's an important point about Kitcher's us of the term "pseudoscientific": the difference between science and pseudoscience is not a sharp difference - as between starters and nonstarters - but a difference in degree. Theories can be more or less pseudoscientific, and there can be borderline cases. So if we employ Kitcher's way of drawing the distinction, we should drop the race comparison, and talk simply of good, mediocre, and bad theories. Our concern will then be with placing theories in a (multidimensional) continuum, and not with deciding who shouldn't be allowed to start the race. Evolutionary theory belongs in the best part of this spectrum. There is no concise, handy principle with which to dismiss theories that deserve to be discarded: there is no substitute for the hard work of seeing whether a theory has the three complex and subtle characteristics in question. Kitcher's own practice is good example: his book's very title makes his attitude toward Scientific Creationism quite clear, but the only way to justify that attitude is to go through a book-length examination of the Creationist criticisms and proposals.

With all that in mind, we can evaluate Scientific Creationism fairly.

[I've often been asked if I 'practice what I preach' - always taking time to do the hard work of evaluating every idea that comes my way. The answer is, of course, "No," and that's not what I meant to be preaching. I do what most people do: use a mish-mash of principles and desires to decide what to investigate thoroughly. Like most people, I have some fairly well-defined professional and family obligations that help narrow the field. Otherwise, I'm driven by curiosity, when I can afford that luxury. Among the principles I use are those that most of us use to decide when (not) to trust a source of information or assertion. Does she have relevant professional credentials? Has she been a reliable, reasonable source in the past, and if so, is there anything special about the present case that should make me skeptical - for example, she hates the theorist whose criticism she's criticizing, she hasn't had a decent night's sleep in six weeks, etc. So I am not counseling the abandonment of common sense.]

A Sign of Trouble to Come

It's worth pausing to look at a Scientific Creationist criticism of evolutionary theory that threatens to gut the latter if it succeeds. In raising some issues about the nature of order and disorder and how they can be explained, it will help us to evaluate Scientific Creationism's use of the notion of design.

Everyone agrees that living things, taken either individually or in populations, are highly - even hierarchically - ordered. A, perhaps the, main goal of biological theories - Scientific Creationism and evolutionary theory among them - is to give an account of this Big Fact. Evolutionary theorists delight in surprising people by saying that the main driving force behind evolution is a random mechanism, namely, mutation, which produces new bits of genetic information (alleles). This sounds counterintuitive because, when we think of randomizing, we think of disorder. Scientific Creationists urge us to hold tightly to that contrary intuition; it spells doom for evolutionary theory. A quick trip to the dictionary instructs us that random mechanisms operate purely by chance. When events occur by chance, they follow no predictable patterns and so cannot be described by the highly regular patterns mandated by natural laws. Instead, random mechanisms, by definition, produce disorder - as anyone who's shuffled a deck of cards surely knows. It's just not plausible to suppose that the random mechanism of mutation could produce the very high degree of order that it is the goal of evolutionary theory to explain. And dragging in natural selection as a constraint on the disorder is hardly enough to yield the extraordinarily high degree of order that living things typify; constrained disorder is still disorder. So, evolutionary theory deploys precisely the wrong sort of conceptual resources to achieve its explanatory goal. The theory is rotten at its conceptual core. To summarize:

Random Argument

If evolutionary theory is true, then the order of living things is produced by a random mechanism (i.e., mutation).

Random mechanisms operate purely through chance, so are not governed by law and produce disorder.

Living things are highly ordered.

Therefore, evolutionary theory is not true

The first and less serious flaw in this argument is in the first premise. Although it is generally agreed that mutation is the more fundamental of two mechanisms for producing variation, there is also recombination of existing bits of genetic information. The first premise focuses on mutation to the exclusion of recombination.

But this is a relatively minor flaw compared to the gross error in the second premise. There is a distinction - not peculiar to evolutionary theory, but familiar to all of us - between apparent randomness and real randomness. Many complex processes are wholly deterministic in the sense that if one knew all the relevant values of variables, one could in principle predict the outcome. But many such processes are so complex that it's unlikely that we will in fact know all the relevant values of the variables. Although the motion of every piece of matter involved may be rigidly predetermined by law-governed physical forces, it all seems 'random' to us because of our partial understanding of how the forces are acting on each piece at each moment. Suppose, for example, that I hurl an open box of Ping-Pong balls into a room full of people. There'll be Ping-Pong balls everywhere, bouncing off walls, furniture, ceiling, and the room's occupants. Eventually, things will settle down and there'll be a final distribution of Ping-Pong ball resting places, aptly describable as a chaotic mess. Although I don't recommend it as a pastime, we could determine this final distribution on a ball-by-ball basis, calculating the trajectory of each through the obstacle course. Because there is no theoretical or practical purpose served by doing so, we are content to rest instead with incomplete, statistical descriptions of the final distribution. In this sense, apparent randomness is an indicator of acceptable levels of ignorance about complex systems.

Much of what evolutionary theorists talk about as random is just this apparent randomness, and a lot of progress has been made in molecular biology and mathematics toward fuller understanding of the processes involved. Another kind of randomness may play a significant role in mutation, operating at the molecular or atomic level. If what a system will do next is a really random event, then it is in principle unpredictable, even on the basis of all the information there is about the system's present state; there is simply nothing in the system now that determines exactly what it will do next. According to what most physicists think about certain atomic processes, atomic events are really random. But even in this case, there are also extremely well-verified laws governing groups of such events (the theory that explains almost all chemical interaction, quantum electrodynamics, has been verified to over ten decimal places), the probabilistic laws of quantum mechanics, which give numerically and geometrically precise descriptions of how these random events array themselves in groups. The charge that no patterns are to be expected there is thus wildly off the mark.

Desperately Seeking Creationism

The time has now come for us to assess Scientific Creationism as its proponents insist that it be assessed: as a scientific theory. In our discussion, we must keep firmly in mind that it is the theory, not its proponents or its origins, that is to be assessed. Its proponents may themselves be good, bad, or anything in between: that's irrelevant. They may have a hidden political agenda: that's irrelevant. The view may be religiously inspired: that's irrelevant, too. So it is no criticism of the theory in this context to say that its proponents want to change the educational and political system by imposing their interpretation of the Bible and what they believe follows from that interpretation. Even if all of those charges are correct, they detract not one whit from Scientific Creationism itself.

This stricture cuts both ways, of course. In this context, it is no defense of the theory to observe that it is religiously motivated, that it accords well with one interpretation of the Bible, or that its defenders may be well-intentioned clergy, theists, and parents who want the best for their children. (And if Scientific Creationism's proponents do wish to claim that its fitting their interpretation of Genesis is evidence for the theory, then they open themselves up to challenges for justification and must admit at least the possibility of counter-evidence as well. Would that be a welcome result?)

So let's take a look at Scientific Creationism. When we try to do so, we encounter a rather odd problem. Evolutionary, right or wrong, is a complex, well-articulated system of hypotheses and explanations. It's been under development for over a century by lots of smart people, and it takes many hundreds of textbook pages just to summarize its current state. But it is very difficult to find any theory at all in the writings of Scientific Creationists. Once one gets beyond their negative remarks about or criticisms of evolutionary theory, there is little in the way of a positive view to be found. A brief look at the best of what they have to say turns out to be enough.

Scientific Creationism: The Fossil Record

There is no disputing the fact that the fossil record is ordered, indeed stratified. Scientific Creationism claims that the record was not produced by evolutionary mechanisms but by a Great Flood that rearranged the remains of organisms made in the initial, simultaneous creation. There is a good deal of vagueness in what they have to say, and a lot of backtracking and sheer avoidance of difficult questions. But the most serious challenge to this claim involves the matter of differential evidence: we have no better evidence for the claim that aliens have periodically tampered with Earth's biosphere, than we have for believing the Great Flood story (Kitcher, 132). It is true that the Great Flood story may accord better with what's suggested by the Bible, but why should that count as evidence here? As long as we are to understand Scientific Creationists to be proposing a scientific theory, as they insist we do, we are entitled, even obligated, to ask them: What independent evidence is there for the truth of this Biblical account, as you interpret it? And they have nothing persuasive to offer.

At this point, and at many others, the proponents of Scientific Creationism take refuge in ignorance and mystery. They say that the detailed mechanisms for ordering the fossil record are forever beyond the power of human beings to know, that the ways of God are many and mysterious, and that it all goes according to God's plan for the world, the Great Design of the Greatest Designer.

What exactly is wrong with this? There are two possible criticisms here, and we must not confuse them. Perhaps you expect me to object at this point that mentioning God makes their reply unscientific. Surely, you might say, if a theory makes reference to God, then it's got to be religion masquerading as science:

Scientific Creationism is pseudoscience because it makes reference to God, the Great Designer of the Universe.

But I do not want to object to Scientific Creationism in this way, and neither do any other clear-headed critics. For example, Kitcher explicitly declines this option, remarking that, " ... postulating an unobserved Creator need be no more unscientific than postulating unobserved [sub-atomic] particles." (125) And we have already considered and rejected Gilkey's criterion, which is in the same family as this one. So reference to God is not the issue. (I'll return to this point in discussing Separation by Reference.) To see what the issue really is, let's first look at another claim made by Scientific Creationism.

Scientific Creationism: The Fixity of Kinds

One of the central tenets of Scientific Creationism is that all the basic kinds of organisms were created simultaneously; it allows, however, that since the Great Flood, some change has taken place in the forms of some organisms, but not in the basic kinds. So the rule for organisms and their ancestors seems to be: once of a basic kind, always of that basic kind. This allows change of only a rather modest sort, since too much change would be incompatible with the preservation of the structure of basic kinds.

One of the most striking recent successes of evolutionary theory is in accounting for the newly discovered biochemical similarities among organisms. Humans and chimpanzees not only share a great deal of genetic material, but are genetically similar, in precisely specified ways, to horses and carp. So, according to evolutionary theory, animals that share a relatively recent ancestor have proteins with similar structures. Can Scientific Creationism account for this sort of similarity? It is sometimes claimed by proponents that these biochemical similarities track with the more traditional similarities among basic kinds, but this is not true in general. For example, humans and chimpanzees are alleged to be of different basic kinds, despite the virtual identity of their cells' biochemical structures. We won't go too far wrong if we think of each basic kind of organism as the object of a separate decision and creative act by God: He saw that the plan required beetles, so He created beetles; He saw that the plan required humans, so He created humans; etc. Given God's nature, however, it was within His power to have fashioned each kind of organism with wholly disparate genetic codes or even from entirely different materials, one carbon-based, another silicon-based, a third from some other material stuff. There is nothing in Scientific Creationism that would lead us to expect the actual overlap among organisms of different kinds.

When pressed, proponents of Scientific Creationism once again claim that the structural similarities and differences among organisms of different basic kinds are all part of God's Great Design: organisms have the features that they have because they need them to serve their part - their purpose - in the divine plan. What is wrong with this reference to design is not the invocation of a deity, but the fact that it explains nothing. It's not that the notion of a Great Design is used that's objectionable; it's how it is used in this context.

In this context, I find it very helpful to look at creation as did the seventeenth century philosopher, mathematician, legal theorist and theologian, Gottfried Wilhelm von Leibniz. Leibniz expended an enormous amount of his considerable intellectual resources on trying to understand creation and he devised an excellent model. According to this model, the universe might have been quite different from the way it actually is - there are infinitely many possible universe designs. Some differ little from the actual one (you and I might be missing from the plan); others differ radically in omitting living things altogether and in having entirely different natural laws (inverse cube, say, instead of inverse square). As an omniscient being, God knows every detail about every possible design for a universe. As an omnipotent being, it is within God's power to implement any one of these designs. But as a supremely good, morally perfect being, it is in God's nature to choose the very best design and to create a universe in accord with it. So, Leibniz argued, this, the actual universe, must be the best of all possible worlds. And since God would not have populated this world with sentient beings wholly unable to appreciate any of the details of His design, Leibniz held, we are endowed with a divinely given cognitive capacity to discern these details and to appreciate them through at least a partial understanding of their mutual fit. Science, on this view, may be thought of as the attempt to discover the details and to answer the question, Why this design above all others? There are more than a few scientists who view themselves as professional students of God's Great Design. Some are even evolutionary biologists, who study (what they take to be) the divinely initiated production process that resulted in us and the world as we find it.

Once we accept the Scientific Creationists' invitation to assess their theory on its merits, we find that their vague gesture in the general direction of a Great Design gives no explanation. If anything is clear about the organisms on Earth, it is that their needs are in large part determined by their 'design'. If fish didn't need to eat, they wouldn't have mouths, digestive tracts, etc. Until we are shown, at least in outline, what the Great Design is and how, in detail, it is a good - indeed, the best possible - design, we have been given no explanation of how its parts allegedly fit together. So if the reference to Great Design is to offer any hope of explanation, it must be specified in much greater detail than Scientific Creationism tries to do. After all, lots of designs were possible: why this particular one?

If, at this point, Scientific Creationism retreats into mystery and ignorance, then it really has withdrawn from the competition with evolutionary theory. It has conceded that explanations of the order of living things are impossible.

But the picture is even worse for Scientific Creationism because, in the end, it is not just one theory in one corner of biology that its proponents urge us to flush; geology, chemistry, and physics will be forced down the drain, too. To see why, let's look at what Scientific Creationism has to say about the age of Earth.

Scientific Creationism: Dating Earth

One of the most widely-known tenets of Scientific Creationism is its claim that Earth is not over 4 billion years old, as most of science would have it, but just a few thousand years old. The details of the procedures used by most scientists to date the rocks on Earth and Earth itself are complex and rooted in extremely well-confirmed, thoroughly tested theories in physics, chemistry, and geology - not to mention evolutionary theory itself. In radiometric dating of rocks, one measures the relative proportions of certain radioactive elements in rocks and then computes the rock's approximate age using a known rate of radioactive decay. Since the way in which the procedures are applied is genuinely complex, it is open to misunderstanding and challenge at a number of points. Kitcher discusses several challenges, responds to them, and tells you where to find additional information. I will mention just one challenge made by Scientific Creationism for the sake of illustration.

In determining the age of rocks by radiometric dating, one assumes that there is a constant rate of decay for each element under consideration. Some Scientific Creationists challenge the assumption of constancy of the rate. That assumption, however, is not a physicist's fantasy but a consequence of the way that nuclear forces operate. Such forces are well understood by physicists, and the particular claim of constancy has been subjected to numerous tests and has passed with flying colors. What we are then faced with here is a particularly stark choice: Scientific Creationism or modern physics.

Notice, as well, that even if Scientific Creationists were to succeed in raising well-taken doubts about dating the age of Earth, they would not thereby establish that its age is but a few thousand years. That requires additional justification - and, as I've emphasized before, according with an interpretation of the Bible is not by itself sufficient justification.

Similar conflicts arise between Scientific Creationism and other well established chunks of contemporary science. In the end, we must reject either Scientific Creationism or much of what is best in science, including its standards and methods.

Angelic Science

"Two Amish Men Accused of Cocaine Deals With Motorcycle Gang," Hanna Rosin, The Washington Post June 24, 1998

Federal prosecutors in Pennsylvania yesterday accused two Amish men of buying cocaine from a gang called the Pagan Motorcycle Club and distributing the drug to other young members of the religious group at parties known as "hoedowns."

"We've seen plenty of underage drinking cases but a drug case is unheard of" among the Amish, said John Pyfer, who is representing Abner Stoltzfus, 24. The other defendant is Abner King Stoltzfus, 23, who is no relation.

The case in Lancaster County underscores the vulnerability of the Amish, who have seen suburban development and tourism encroach on their once secluded lives. The suburbanites and the gawkers have made it difficult for the Amish to close their eyes to what they consider the corrupting influences of modernity. Members of the sect do not have electricity or plumbing in their homes, and still make their way around the county in horse-drawn buggies. The two men accused belong to the most conservative Amish sect, the Old Order Amish.

Most work as farmers or craftsmen, and do not stray far from their homes. Abner Stoltzfus worked as a roofer, Pyfer said, and met Pagan members on his work trips outside Lancaster.

The two men were indicted yesterday on charges of participating in a conspiracy to distribute more than $ 1 million worth of cocaine and methamphetamine. Federal prosecutors placed most of the blame on eight members of the motorcycle gang, who were described as reckless and violent. Emory Edward Reed, president of the Pagans' Chester County chapter, broke one of the defendant's legs with an ax handle when he refused an order, and knocked out the other defendant's teeth when he failed to pay on time.

While members of the biker gang were known as habitual lawbreakers, no one from the Amish had ever been involved in such serious criminal activity, attorneys said. The two Amish men allegedly bought the drugs from gang members between 1992 and 1997 and distributed them at parties of youth groups known as the Antiques, the Crickets and the Pilgrims. A juvenile identified only as CS also participated in the conspiracy, according to prosecutors, but was not charged in the indictment.

Pyfer said "it was pretty clear" his client had been addicted to cocaine, although he no longer is. No date has been set for the arraignment, but Pyfer said his client would plead not guilty.

During the five years the two men were allegedly distributing cocaine, they were participating in an Amish rite of passage translated loosely in English as "sowing your wild oats," said Pyfer. Amish men between the ages of 16 and 24 take a long break from the rigid rules of the community to decide if they want to opt out. During the break, the men drink and drive "bright, gaudy cars," said Pyfer, while "their parents are looking the other way." Taking drugs is not an accepted part of that rite, however.

"Exorcist called in to rid church of devils" (Agence France Presse).

DELAIN, France, Oct 21, 1998 (AFP) - An exorcist has been called in to rid the village church of devils which sent candlesticks flying, forcing ecclesiastical authorities to close the building down until further notice.

The exorcist, Father Max de Wasseige, who was called in by the archbishop of Besancon to drive out the devils, said "I saw candlesticks flying about with my own eyes."

The trouble began last Thursday in this church in eastern France when volunteers moved the altar by a few centimetres to make more space for a visiting symphony orchestra.

Witnesses said afterwards that a candle went flying, splitting in two, and that statuettes and vases were broken inexplicably. Also the altar was moved by 10 centimetres (four inches), apparently unaided.

Delain mayor Thierry Marceaux said "There was no collective hallucination, or 50 people will have to be sent to the lunatic asylum."

He said the orchestra gave its concert as normal on Sunday, but that the devils resumed their work on Monday even though the altar had been put back in its place. A broken, still-warm, candle was found on the floor at a place where there is no candlestick.

"Religion Journal; Is Satan Real? Most People Think Not" by Gustav Niebuhr, The New York Times May 10, 1997

... a recent finding by the Barna Research Group, market researchers in Oxnard, Calif., ... reported last week that nearly two-thirds of Americans do not believe in the Devil as a living entity.

In a nationwide telephone survey of 1,007 randomly selected people earlier this year, Barna's pollsters asked whether they agreed that Satan is "not a living being, but is a symbol of evil." Sixty-two percent agreed with the statement, while 30 percent disagreed; the remaining 8 percent had no opinion. ...

Belief in a literal Satan can certainly find a basis in Scripture, ... In the Bible, the Devil appears, most famously, as Job's tormentor and Jesus' tempter. ("Get thee hence, Satan," Jesus declares in Matthew 4:10, rebuking the Devil for having offered Him "all the kingdoms of the world.") ...

Yet there are many for whom the Devil remains a reality, the ultimate and undiminished embodiment of evil.

Among those belonging to this group is most of the membership of more than 15 million in the Southern Baptist Convention, said William Merrell, that evangelical denomination's vice president for convention relations.

"I think the vast majority of Southern Baptists would believe that Satan is a real personage, not someone to be taken lightly," he said. "He is the implacable enemy of all God's people." ...

We would all like to know why the two Abners went astray. Given that a significant minority of the American population believes in angels, fallen or otherwise, there seems to be a gap in the educational program of proponents of Scientific Creationism. "The Devil made me do it" would seem from their perspective to have as much to recommend itself as "God made all living things." Why have not they not pressed for similar application of purpose-directed explanation in psychology? It may be that modern Satanism (not to mention the Inquisition) has given this idea a bad name, which suggests that it is all the more important for proponents of Scientific Creationism to rescue the underlying ideas from such bad press. The question becomes even more puzzling when we look at the depth of parallels between Scientific Creationism and Angelic Science. For the sake of brevity, let's look only at Satanic Science, or demonology; but much of what can be said about the latter will also apply to the systematic study of non-fallen angels and their role in human affairs.

Like Scientific Creationism, Satanic Science is well-grounded in the Bible and in subsequent theological writings. (I say "is" rather than "would be" since there is an extensive professional literature, focusing on both theory and application, in Christian demonology alone. More of that later.) For example, the book of Revelation describes Satan in the form of the ten headed dragon as he does battle with the armies of God, led by Michael. At Job 4:13: "If God places no trust in his servants, if he charges his angels with error.." These passages can also be given as scriptural warrant for belief in angels:

Old Testament references: Cherubim at entrance to Garden of Eden Gn 3:24; Appear to Abraham Gn 18:1-33; Saved Lot and his family Gn 19:1-22; Intervened with Isaac Gn 22:11-18; Heavenly vision of Jacob's Ladder Gn 28:12; Accompanied Israel through the desert Ex 23:20; Nm 20:16. Aided the prophets: Isaiah IS 6:2-7; Ezekiel Ez 1:4-28; Daniel Dn 7:9-10; Zechariah Zec 1:9-19.

New Testament references: Appeared in connection with birth of Christ Mt 1:20 Lk 1:26-38. Appear to: Paul Acts 27:23; Peter Acts 12:7-11; Cornelius Acts 10:3-6; Sadducees didn't believe in angels Acts 23:8; 12 Legions of Angels Mt 26:53. Mentioned by name: Raphael Tb 12:15; Michael Dn 10:13 Rv 12:7; Gabriel Dn 8:16 Lk 1:19. Fall of the angels: Dt 32:17; 2 Pt 2:4; Jude 1:6; Rv 12:7-9.

The notion that there are satanic influences in the universe also plays a key conceptual role in the Free Will Defense, one resolution of the classic Problem of Evil, most forcefully be stated as a challenge to the existence of God as conceived in the main Western religious traditions:

The Problem of Evil

If God exists, then there is an omnipotent, omnibenevolent, omniscient creator of the universe.

If there is omnipotent, omnibenevolent, omniscient creator of the actual universe, then the actual universe is be the best possible universe.

If the actual universe is the best possible universe, then the actual universe contains no evil.

The actual universe does contain evil.

Therefore, God does not exist.

The first premise is true by the relevant definition of "God." The second premise seems true because God, as an omniscient being, will know which universe is best; being omnipotent, God will have the power to create any possible universe; and being omnibenevolent, God must choose to do what is best by creating the best possible universe. In favor of the third premise, it seems that a universe containing no evil at all is better than a universe that containing some. And the fourth premise seems to have all too much support: our own corner of the universe often seems full of evil.

This problem has a long history, with many versions having been studied and many more replies offered. One of the more persuasive replies denies the third premise, arguing instead that the best possible universe must contain some beings with free will - for example, us - since free will is such an enormously great good in itself. But genuinely free beings will sometimes make mistakes, and evil will result. This Free Will Defense, as it is called, has a weakness, however: it does not account for natural evil, the kind that results from natural disasters such as disease, hurricanes and volcanic eruptions. There is, however, a natural extension of the Defense to address natural evil: just as free humans bring about evil, so do free non-humans, among which are Satan and his legions, and it is they who are responsible for the natural evil in what is nevertheless the best possible universe.

While the problem and the Defense deserve longer, more careful discussion, perhaps this brief summary is enough to show that an important conceptual role is played in religion by the notion of a fallen, superhuman entity.

Like Scientific Creationism, modern demonology would be able to rely on a substantial prior literature, one that stresses both theory and application. On theory, one of the best known works is the Malleus Maleficarum, the main guidebook of the Spanish Inquisition. As Paul Feyerabend remarks in "The Strange Case of Astrology,"

The Malleus is a very interesting book. ... The description of phenomena is sufficiently detailed to enable us to identify the mental disturbances that accompanied some cases. The aetiology is pluralistic, there is not just the official explanation, there are other explanations as well, pluralistic explanations included. ... alternatives are discussed and so one can judge the arguments that lead to their elimination. This feature makes the Malleus superior to almost every physics, biology, chemistry textbook of today. Even the theology is pluralistic, heretical views are not passed over in silence, nor are they ridiculed; they are described, examined, and removed by argument. The authors know the subject, they know their opponents, they give a correct account of the positions of their opponents, they argue against these positions and they use the best knowledge available at the time in their arguments.

Of course, the way in which the theory was used by the Inquisitors was often itself horrific, but the theory is not to blame for their excesses; after all any theory can be misapplied by unscrupulous power-mongers.

In both biology and psychology, it is important, as well as very interesting, to explain malfunction as well as normal function, for it is in this way that the normal is clearly distinguished from the abnormal. Some moral urgency may also attach to the restoration of normalcy for a creature, human or otherwise, who has fallen below normal. Teratology, which studies congenital malformations, provides some of the most poignant examples of malfunction in the life sciences, and evolutionary theory and Scientific Creationism must both have something to say by way of explanation of these sometimes horrendous "mistakes" of Nature. Of course, for Scientific Creationism, there are no real mistakes in God's design; there are only apparent flaws that seem unnecessary because the relevant purpose-directed explanation has not been given sufficient depth - and, on the Creationist view, it may not always be within human powers to do so. Likewise, abnormal psychology and demonology need to address abnormal human thought and behavior, not only to aid in restoration of normal function, but also to help us assess the degree to which moral responsibility for behaviors are diminished. Many complain about the "medicalization" of evil in modern psychotherapy and psychiatry; by letting people off the hook as diseased, some say, we miss the very real evil that infects their behavior. If, however, we are to make the relevant moral judgments reliably, we must take special care that a demonically purpose-directed explanation is given due consideration. For example, in the heart-rending case of the two Abner Stolzfus's, as described at the beginning of this section, one may wish to consider the possibility that this apparent failure of family values to take appropriate hold in these young men is really the work of the devil. (This is not to imply that the religious views of the Amish themselves would warrant such consideration.)

For application, there are carefully specified procedures for exorcism, the main therapeutic method for dealing with demonic possession. These procedures include detailed guidelines on differential diagnosis: it is crucial to determine if the person presenting with undesirably deviant behavior is suffering from a physical or mental disease, or if the person is in fact possessed. In one especially careful article on Multiple Personality Disorder (MPD), at his web site on trauma and religious issues [http://www.jmahoney.com/exorcism.html], Father Mahoney recommends the following precautions:

If someone is diagnosed as having MPD based on other personalities, a demonic presentation should be presumed to simply be another personality, unless clearly demonstrated otherwise.

An MPD personality will have an identifiable time of formation and functional role within the personality system consistent with the trauma as it was occurring. MPD specific therapy will result in psychologically consistent change in that personality, with improvement over time in the presence of a healthy therapeutic alliance.

As the personality is worked with, emotions such as rage will be clearly "human" in origin, and if the personality is more developed there will be the clear existence of state-dependent learning. Knowledge possessed will be appropriate to the role and function of the personality.

Unusual phenomena will be those seen and reported in at least some other patients clearly diagnosed with MPD, and will follow the general patterns for those phenomena.

Unusual phenomena consistent with true possession would be clearly outside the "natural order" and/or would be situations not reasonably accounted for by science.

There are strange phenomena that are frequently seen and observed in MPD patients. They are accepted as MPD dynamics, and are often present with some personalities and absent with others. In different patients, they may or may not be linked with a subjective sense of "being evil" and are clearly linked both to trauma and attempts at adapting to that trauma. These phenomena would include at least the following:

Susceptibility to hypnosis and an unusual ability to cause others to enter hypnotic or trance states.

Body memories having physical characteristics. These are reenactments of past trauma and follow the same characteristics as the classic stigmata phenomena. They may appear and disappear without external manipulation and may include rashes, welts, cuts, burns, blood, swelling, and significant physiological changes.

Apparent telepathy, clairvoyance, and unexplained knowledge. These may reflect hyperacute senses, such as hearing thoughts reflected in the movement of the larynx. Photographic state-dependent memory, extremely acute awareness of others' body language and visual cues, and unusual mental feats are also common.

Physical strength beyond ordinary perceptions of what is humanly possible.

Highly accelerated healing, control of bleeding, and ability to regulate physiological states in ways not normally considered possible or under conscious control.

Ability to cause in an observer a sense of cold, evil, or threat.

Acts of self-harm and extreme self-mutilation, hatred of God and religious objects.

Ability to go for long periods with neither food or sleep.

Selective, personality specific anesthesia and the blocking of normal pain stimuli.

It should be noted that many unusual phenomena that are considered in popular culture to be "psychic" or otherwise unexplainable are often based on the skills and illusions of magicians, the use of various forms of trance states, suggestibility, intentional fraud, etc.

These, of course, are the very sorts of guidelines that we'd hope would be carefully observed when demonic hypotheses about deviant behavior were also being taken seriously.

It is common for historians of medicine to recount demonic explanations offered of long past plagues; for example, in "The dancing plague: a public health conundrum," Public Health 1997 Jul; 111(4): 201-4, the authors LJ Donaldson, J Cavanagh, and J Rankin, write,

The phenomenon of mass, frenzied dancing affected large populations in various parts of Europe from the thirteenth century and lasted, on and off, for three centuries. The exact aetiology of the Dancing Plague (or Dancing Mania) is still unclear. Retrospective historical review of this public health problem reveals claims for causative factors including demonic possession, epilepsy, the bite of a tarantula, ergot poisoning and social adversity. It seems unlikely that Dancing Mania resulted from a single cause but rather resulted from multiple factors combining with a predisposing cultural background and triggered by adverse social circumstances. Dancing Mania remains one of the unresolved mysteries of public health.

And what were once seen as incidents of demonic possession are now understood as the result of simple physical ailment, such as poisoning or epilepsy, as suggested in

Kemp-S; Williams-K Demonic possession and mental disorder in medieval and early modern Europe. Psychological Medicine 1987 Feb; 17(1): 21-9

ABSTRACT: Western European belief in demonic possession as a cause of mental disorder has been traced through the medieval and early modern periods. Generally it appears that the range of disorders attributed to demonic possession has gradually narrowed. In any period, however, there seem to have been marked individual and cultural differences in outlook; some of these differences are still evident today in the survival of belief in demonic possession in pentecostal sects.

Spanos-NP Ergotism and the Salem witch panic: a critical analysis and an alternative conceptualization. J-Hist-Behav-Sci. 1983 Oct; 19(4): 358-69

Eadie-MJ The understanding of epilepsy across three millennia. Clin-Exp-Neurol. 1994; 31: 1-12

ABSTRACT: The phenomena of epilepsy have been known for at least 3000 years, the earliest recorded account being in an Akkadian text called the Sakikku (written around 1067-1046 BC). Over nearly all the subsequent centuries the popular belief has been that epilepsy is a disorder of supernatural origin, and to some extent such ideas have carried over into medical thought. In Western civilisation, the long dominant belief was that epilepsy was due to possession by a devil or a demon, an interpretation given authoritative support by the miracle story of the cure of the epileptic child which is recorded in all three synoptic Gospels. However, there have been many other interpretations e.g. epilepsy as a consequence of wrong doing or of lunar or magical influences. Such ideas began to die out only in the past 200 years. From Hippocrates (c. 400 BC) onwards, there has been a continuing line of thought that considered epilepsy a medical condition due to natural causes. The hypotheses concerning its pathogenesis have ranged from excess phlegm in the brain, through boiling up of the vital spirits in the brain (Paracelsus), explosion of the animal spirits in the centre of the brain (Willis), heightened reflex activity at a spinal (Marshall Hall) or medullary level (Brown Sequard), to Hughlings Jackson's notion of an occasional, an excessive, and a disorderly discharge' in part of the cerebral cortex. Among thinking men, epileptology in the past century has proved largely to be a matter of exploring the ramifications of Jackson's concepts.

de-Villiers-JC A few thoughts on the history of epilepsy. S-Afr-Med-J. 1993 Mar; 83(3): 212-5

ABSTRACT: The history of epilepsy is a saga of the struggle by which scientific understanding of an unusual disease was gained by a long and circuitous route. In the beginning this affliction was attributed to demon possession and defied understanding for centuries when it was still regarded as a sacred disease and surrounded by superstition and mysticism; therapy of necessity had to follow similar lines of reasoning. The gradual realisation that cerebral dysfunction was the cause of this disease was highly significant although still followed by misunderstanding and misinterpretation--those two essential steps to progress. Clear, inspired reasoning and lucid clinical descriptions of epilepsy by John Hughlings Jackson and William Gowers set the scene for what was to follow. Experimental neurophysiology, cortical simulation, cortical localisation, new technologies of electro-encephalography, modes of visualisation of structures histologically and radiologically led to our present-day concepts of this complex disorder. We have been brought to new thresholds of understanding through the co-operative exertions of many workers from all parts of the world and this saga tells of some of the highest scientific accomplishments in medicine.

Sjoberg-RL False allegations of satanic abuse: case studies from the witch panic in Rattvik 1670-71. Eur-Child-Adolesc-Psychiatry. 1997 Dec; 6(4): 219-26

ABSTRACT: The creation of false memories, psychiatric symptoms and false allegations of satanic child abuse during an outbreak of witch hysteria in Sweden in the seventeenth century are described and related to contemporary issues in child testimonies. Case studies of 28 children and 14 adults are presented. The mechanisms underlying the spread of these allegations, as well as the reactions and influence of the adult world on the children's testimonies, are discussed.

Just how difficult and important differential diagnosis will be is highlighted by these two very recent articles:

Ferracuti-S; Sacco-R; Lazzari-R Dissociative trance disorder: clinical and Rorschach findings in ten persons reporting demon possession and treated by exorcism. J-Pers-Assess. 1996 Jun; 66(3): 525-39

ABSTRACT: Although dissociative trance disorders, especially possession disorder, are probably more common than is usually though, precise clinical data are lacking. Ten persons undergoing exorcisms for devil trance possession state were studied with the Dissociative Disorders Diagnostic Schedule and the Rorschach test. These persons had many traits in common with dissociative identity disorder patients. They were overwhelmed by paranormal experiences. Despite claiming possession by a demon, most of them managed to maintain normal social functioning. Rorschach findings showed that these persons had a complex personality organization: Some of them displayed a tendency to oversimplify stimulus perception whereas others seemed more committed to psychological complexity. Most had severe impairment of reality testing, and 6 of the participants had an extratensive coping stile. In this group of persons reporting demon possession, dissociative trance disorder seems to be a distinct clinical manifestation of a dissociative continuum, sharing some features with dissociative identity disorder.

Goodman-GS; Quas-JA; Bottoms-BL; Qin-J; Shaver-PR; Orcutt-H; Shapiro-C, Children's religious knowledge: implications for understanding satanic ritual abuse allegations Child-Abuse-Negl. 1997 Nov; 21(11): 1111-30 [Comment in: Child Abuse Negl 1997 Nov;21(11):1109-10]

ABSTRACT: OBJECTIVES: The goals of the present study were to examine the extent of children's religious, especially satanic, knowledge and to understand the influence of children's age, religious training, family, and media exposure on that knowledge. METHODS: Using a structured interview, 48 3- to 16-year-old children were questioned about their knowledge of: (a) religion and religious worship; (b) religion-related symbols and pictures; and (c) movies, music, and television shows with religious and horror themes. RESULTS: Although few children evinced direct knowledge of ritual abuse, many revealed general knowledge of satanism and satanic worship. With age, children's religious knowledge increased and became more sophisticated. Increased exposure to nonsatanic horror media was associated with more nonreligious knowledge that could be considered precursory to satanic knowledge, and increased exposure to satanic media was associated with more knowledge related to satanism. CONCLUSIONS: Our results suggest that children do not generally possess sufficient knowledge of satanic ritual abuse to make up false allegations on their own. However, many children have knowledge of satanism as well as nonreligious knowledge of violence, death, and illegal activities. It is possible that such knowledge could prompt an investigation of satanic ritual abuse or possibly serve as a starting point from which an allegation is erected.

There is even some limited clinical evidence for efficacy of exorcism, as suggested in a recent 60 Minutes feature. In the case depicted, exorcism seemed to work when standard therapy and medication did not, and there are other reports in the psychiatric literature (e.g., Dr. Fraser's from the Royal Ottawa Hospital in Canada). Here, too, we must be careful to consider the power of (ordinary, human) suggestion in addition to the well-known placebo effect. But then they must always be taken into account as possible explanations.

There thus seems to be no compelling reason for proponents of Scientific Creationism not to press the case for teaching Satanic Science in, for example, public school social science classes, where the darker portions of human history (e.g., crime, war) must inevitably be discussed. And at the college level, courses in abnormal psychology might also find a place for discussions of demonic possession as a possible diagnosis for abnormal behavior. While Satanic Science may in the end fare no better as a theory than did Scientific Creationism, that certainly does not explain the failure of the latter's proponents to advocate the teaching of the former. Indeed, this failure seems intellectually indefensible, given the parallels noted. So I remain puzzled about that failure.

New Age Resonances

Scientific Creationists misuse purpose-directed explanation in the pursuit of their religiously inspired aims. But New Agers dilute purpose-directed explanation to the point of disappearance. When it was first suggested that I discuss New Age beliefs in this book (thanks very much, Professor Kitcher), I despaired of finding sufficient intellectual content in them to warrant their examination. They are such a varied lot that it was not at all clear to me that they had more than the label in common; nor was I hopeful that I could find interesting 'family resemblances' among them. Further investigation did, however, yield a bold, somewhat cynical, two-part hypothesis, which I'll now present.

It seems typical of New Age beliefs to focus on resonances between disparate entities, for example, you and a crystal, or you now and you in a past life. At least, the term "resonance" appears fairly often and looks to be used in roughly similar ways in the New Age literature. What is it a term for? It is not mere similarity that is connoted; rather, it is similarity conceived of and explained in a particular way. That way is given voice in

The Fundamental Principle of the New Age: Every similarity has a purpose-directed explanation.

Or, equivalently, every similarity is a pattern that is in turn a purpose-indicator.

Whatever the failings of Scientifc Creationists, they do not lose sight of the fact that purpose-directed explanation derives its power from a conceptual distinction between purpose-indicators and relations (among parts or stages) that are not purpose-indicators. The Fundamental Principle, by linking of the concepts of similarity, purpose-indicator and explanation, imposes such great stress on them that they lose structural integrity. The effect is to wash out distinctions and to dilute the notion of purpose-directedness so much that it loses its identity. After all, any two things will be similar in some, perhaps very simple and obvious, way.

Why then do New Age leaders often speak in ways that are inconsistent with their Fundamental Principle? Here we need to augment a standard, tripartite distinction familiar to all who study the workings of language. Rudolf Carnap, the logician and philosopher, suggested that a language has three aspects: syntax, semantics, and pragmatics. Very few know that he had a half-brother, Rolf, who for many years ran Chicago's largest sausage factory. Rolf was often heard exhorting his employees, "Never mind what's inside! Marketing's the thing!" In making sense of the speech acts of New Age leaders, I suggest that we pay close attention to syntax, semantics, pragmatics and marketing. And I offer this bold, falsifiable, empirical hypothesis: to the extent required by marketing considerations, they will depart from the Fundamental Principle. If a potential follower becomes skeptical to the point of financial reticence over the Fundamental Principle's absurdly watered-down 'use' of purpose-directed explanation, they will postulate the minimum restriction on purpose indicators that will reopen the wallet.

If these bold hypotheses about the New Agers are correct - and I look forward to lots of grant money to support the urgently needed research - then the main challenge will be to explain the enormous diversity of New Age systems. But the outlines are now clear. After all, there is bound to be disagreement among New Age leaders about how to restrict the application of the Fundamental Principle in a way that optimizes unidirectional cash flow.

I'm inclined to leave it at that, but I've found that some attempts at mild humor need to be highlighted as such, lest they be mistaken for serious proposals.

When confronted with the task of disentangling a bowl of multicolored spaghetti (add sauce to taste, for marketing), it is tempting to impose order on the material. My bold hypotheses, while not entirely frivolous - I meant what I said about the contrast with Scientific Creationism - do very little to explain or even neaten the chaotic mess of New Age beliefs. The sources of those beliefs are so varied and so often re-mixed that what they have in common is really nothing more than being labeled "New Age." And the reasons for the labeling are so varied and so often remixed, not to say mixed-up, that there's no longer any "there" there (apologies to Gertrude Stein). The strategy that I used to impose a false order to the subject, is, however, a disturbingly common one that you ought to watch out for. I began with respectable, fairly well-understood concepts and distinctions and then put them together in such bizarre ways that it became difficult to retain any sense of the originals, although the puzzlement at seeing them so linked may have temporarily upset your sense-detectors. The distinction among syntax, semantics, and pragmatics is an important and moderately well-defined one in the serious study of natural and formal languages, but the adjoined category of marketing is nothing better than a dump - a repository for the messy stuff that we haven't taken the trouble to sort out. No problems are solved by slapping a label on the unsolved ones. So, be on the alert for pseudoscientific accounts of pseudoreligion. Caveat emptor!

Chinese Acupuncture - A Useful Theory

"I'm a practical kinda guy/gal. What I want are theories that work. What more could one want from a theory than practically useful predictions? Anything else is a waste of time and money." It's hard not to have some sympathy with the underlying sentiment here. Given all the pain and difficulty with which life is full, and given our limited resources for dealing with them, some impatience with the 'merely theoretical' is to be expected. But a moment's reflection shows that a predictively successful theory that does not explain what it predicts will be far less useful than one that also explains, since the latter will also have a wider future application. Suppose, however, that a theory gave precise and accurate guidance throughout its domain of application. Wouldn't that also guarantee that it was a good explanation? It's not hard (and can be a lot of fun) to cook up screwy theories that match observed outcomes exactly, if one can work backwards from a good theory. But it can also be done without cheating in this way. Let's consider the possibility of super-acupuncture.

Chinese acupuncture is a very old and widely implemented medical theory that postulates the existence of Qi energy in the universe and seeks to explain human maladies as Qi imbalances. It is these imbalances that the insertion of needles into (or the burning of herbs near) the skin (moxibustion) are supposed to correct by restoring proper patterns of energy flow. This description might lead you to think of the ways in which we redirect the flow of water by building or removing dams, shifting river banks, and constructing other systems of gates and channels; or, if you are more electrically inclined, to think of electrical current flow in circuits - a closer analogy to the functioning of the human nervous system. According to standard texts on acupuncture, however, Qi energy is not like any other kind of energy and is itself undetectable. The flow patterns in health and disease can, it is also said, be inferred indirectly, and the texts offer elaborate maps of flow patterns.

There is no question that the practice of acupuncture is useful in inducing some sorts of anesthesia. There is also no evidence that its success has anything to do with Qi energy, and there is excellent reason to think that there is no such energy. The maps of Qi flow lines do overlap with some of the paths of nerve fibers in our bodies, but so would any map with enough lines on it. (Imagine wrapping yourself in rubber-sheet graph paper.) What acupuncturists have managed to do, through a great deal of trial and error, is to find some points for needle insertion that have pain-relieving or -preventing effects. But this is not based on an understanding of neuroanatomy.

Imagine, however, that we give acupunctural research more time and many more subjects, so that researchers can conduct many more trials and learn from their numerous errors - which, unfortunately for the subjects in this case, won't be hard to spot. Given enough trial and error, it is conceivable that a system of needle insertions could be developed that did as much as it possibly could for a human being - without ever having to study the details of human nervous function. Would such Super-acupuncture be scientific because all of its predictions are true and it is very useful (in its intended domain)? It seems not, because it would still fail utterly to explain why needle insertion ever works to relieve pain or block other nerve functions. And its practical utility would be severely limited by this failure. A good theory of human nerve function would have much greater theoretical interest and practical utility. It would help us to deal with any malfunction of the nervous system.

Saucers and Sex - UFOlogy and Sexology

"Saucer sightings and sex - not worth investigating and best left to kooks and perverts." There are, it seems to many, subjects that are beyond respectable scientific inquiry. Even the reports of UFO sightings are confined mainly to tabloids ("I SOLD MY BABY TO UFO ALIENS!" screams the headline) and enthusiasts' newsletters. And judging from the behavior of parents, teachers, clergy, legislators, and others in authority, sex is a personal, subjective matter, best left virtually undiscussed.

This desire to declare some subjects off limits to scientific investigation is similar to the second objection to parapsychology: it's virtually certain that no reliable evidence about the relevant phenomena will be discovered. But in this case, it is not the methods that are in question; rather, the phenomena themselves have features that allegedly make their scientific study infeasible.

UFOlogy

UFOlogy is pseudoscience because we know that it is very unlikely that alien spacecraft have visited Earth.

Such reservations about subject matter can be countered by showing how to approach these subjects scientifically. In each case, there are broader questions of clear and considerable scientific interest that include UFOlogy and sexology in their scope.

The broader question for UFOlogy is, of course, Is there extraterrestrial life? and its variants: How likely is it that there is extraterrestrial life? How likely is it that Earth has been visited by any such life? How likely is it that there have been any close encounters? And there is the deeper question, which we will pick up later, What is life?, and how closely tied to terrestrial examples should the concept itself be?

Arguments for the existence of such life fall into two kinds, both of which were exemplified in ancient times. Because they have not changed in their essentials since then, I will present ancient versions of each. The first was offered by Plutarch and is an argument from design; the second, given by Lucretius, has a very modern ring because it avoids notions of design and instead relies on chance in atomic theory.

Plutarch's Purpose Argument

Plutarch begins by arguing that Earth was designed for the purpose of supporting life. His argument stands in a long tradition of arguments from design. In their most controversial uses, they purport to show that the universe itself was designed by a divine being. But, as hinted in the discussion of the Argument from Design (Vegetabilist Version - see the discussion of Separation by Standards in the next chapter), such reasoning has more everyday, nontheological, uses. We are surrounded by artifacts that show a purposeful arrangement in their parts. Although we can often tell what the purpose is, sometimes - when, for example, the artifact is a complex, unfamiliar piece of laboratory equipment - we can tell little more than that the arrangement is for a purpose (or purposes) we've not been able to discern. The patterns exemplified by such arrangements can also be found in processes. For example, both a camera's stable structure and the production process that results in that structure give us an indication of purposiveness; and in this case, we can tell that picture-taking is the purpose in question. Let's call the relevant sorts of patterns "purpose-indicators." Wherever we find purpose-indicators, we readily conclude that it's very likely the object was designed for its purpose(s). But why draw such conclusions only about human artifacts? After all, we can observe purpose-indicators in many natural objects and processes. The reasoning seems to apply with equal force to, say, eyes, as to cameras, both of which 'take pictures'. Why not conclude that the eye, too, was designed for its purpose? Plutarch employed exactly analogous reasoning about Earth. He began by observing that Earth is a complex object that exemplifies the purpose-indicator of supporting life. So, he reasoned, Earth was designed to support life. Plutarch then claimed that there is a heavenly body that can be observed to be like Earth in exemplifying the purpose-indicator of supporting life. If so, then it is unlikely that its intended purpose would go unfulfilled. So, very likely, it, too, supports life. Plutarch's astronomy was a bit off: he thought that the heavenly body in question was the Moon. Now we know better. But we also have better ways of making astronomical observations. With the additional assistance of astrophysical theories of planetary formation, we can find reason to believe that there are Earth-like planets Out There. If we accept the principles linking purpose and design, we, like Plutarch, have some reason to believe in extraterrestrial life somewhat similar to life here.

While purpose-directed explanation has real power, applying it is a subtle matter. There are three issues that Plutarch's Purpose Argument raises and that will affect the other applications of purpose-directed explanation we will be considering later. First, we need to know which patterns are purpose-indicators and which are not, and we need to know what counts as evidence of their presence. Analogies between natural objects and artifacts made to resemble them (e.g., eyes and cameras) are instructive, but they don't answer this first set of questions in a general and precise way. Second, we need to figure out how the purpose-indicators confer particular degrees of likelihood on the conclusion that the object was designed. In effect, we need a mathematical function that looks at purpose indicators and yields a numerical probability as output. Third, we need to determine the actual kind and degree of similarity between the purpose indicators of Earth and heavenly companions and to construct a theory that will tell us how life develops under such similar constraints. The first two issues have kept some of the best minds busy for a couple of millennia, and they're not done yet. The third issue will require significant advances in both astrophysics and biology. So, when I say that we have some reason to believe in life Out There if we accept Plutarch's application of purpose-directed explanation, the reason is very weak and could well be defeated by future theoretical or observational progress.

Lucretius's Luck Argument

Lucretius denied the very existence of purposive beings and designers, and instead held that the universe consists solely of infinitely many material atoms moving about in the infinite void (space without bounds) through infinite time. With so many atoms and so much space and time for them to move in, every possible pattern of atomic arrangements will be repeated infinitely many times in infinitely many places. Since one such pattern is life on Earth, we are guaranteed the existence of extraterrestrial life just like us. So, Lucretius held, you have infinitely many indiscernible twins (as do Fido and Fluffy) scattered throughout the cosmos.

Lucretius even had available an argument for the infinity of the void. Suppose, for the sake of argument, that space were not infinite. Then it must have an edge or boundary. Imagine standing near the boundary and conceiving of what lies beyond it. By hypothesis, nothing lies beyond the boundary, but what is nothing but more empty space? So it is inconceivable that space itself has a boundary, and whatever is inconceivable is impossible. Hence, there is no boundary to space after all. So space is unbounded, which in turn means that space is infinite. Aside from the assumption that what is inconceivable is impossible ­ are our minds really such reliable guides to impossibility? ­ the final step of the argument is questionable. If we are like bugs on a balloon, then we could go anywhere and everywhere without ever meeting a boundary, despite the fact that our domain was no bigger than the balloon's surface. Perhaps our own three-dimensional space is spherically folded in such a way and is thus unbounded but finite. Contemporary cosmologists say things that suggest this is a real possibility. I have a hard time grasping just what they mean (and I suspect they do, too). But apart from the weakness of this subordinate argument, there is another problem with Lucretius's proof of the existence of extraterrestrial life.

The main problem with his argument is that, although the duplication he describes is possible on his view of the universe, it is also possible that the pattern here is never repeated anywhere else because it is possible that lifeless collections of atoms are repeated endlessly throughout space and time ­ except here on Earth. It takes an additional argument to show that the randomness of atomic motion guarantees the actual occurrence of every possible configuration at some place or time. As we've see in the discussion of Scientific Creationism, however, randomness is not an easy concept to manage, and we shouldn't be too hard on Lucretius for having assumed that it would work in his favor.

Both Plutarch and Lucretius had concepts of living thing tied closely to terrestrial examples. If we loosen the ties, then we need to redraw the boundaries of the concept of living thing, and this will reshape the question of extraterrestrial life. Biologists have speculated that noncarbon-based life is possible, and some computer scientists have suggested that living things are mainly devices for preserving (genetic) information, so a chemical basis is unnecessary ­ a self-reproducing automaton, or automata capable of "machine sex," should be counted among the living. We will return to some of these issues when we tackle the meaning of "life."

Sexology

Sex, a great and mysterious motive force in human life, has indisputably been a subject of absorbing interest to [hu]mankind through the ages; it is one of the vital problems of human interest and concern.

Justice William J. Brennan, Roth v United States, U. S. Supreme Court, 1957

Although Justice Brennan's remark has been derided as too obvious, no one should deny the truth it expresses. But many seem anxious to keep the truth out of public view, as if knowledge of sex were itself a violation of privacy. Sex is a subject severely, perhaps uniquely, infected by guilt, shame, anger, fear, and ignorance, and these characteristics feed on themselves and one another, discouraging people from asking (much less trying to answer) often urgent questions about both quality and quantity of life. Research about sex is, therefore, extraordinarily difficult, not just because it seeks to study complex phenomena, but because powerful social and political forces pervert and distort the subject and the potential subjects. Justice Brennan's insight notwithstanding, the situation may seem hopeless:

Sexology is pseudoscience because we know that its information sources are highly unreliable (because they are contaminated by self-perpetuating anger, fear, guilt, shame, and ignorance).

Two recent publications reinforce this impression of hopelessness.

In 1995, the Social Science Research Council issued a report on the state of sexuality research in the United States. What is striking about the report is not that it lists about fifty major unanswered questions ­ every 'standard' branch of science has plenty of unanswered questions ­ but that the questions concern such elementary and basic conceptual and empirical matters. Here are a few examples:

What individual behaviors, abilities, attributes, motivations, and practices contribute to sexual health?

How is sexuality defined and what does it signify or represent over the life span for individuals in varied and changing social roles?

How are male and female roles and attributes assumed and what is the significance of this process for sexual behaviors expressed at various developmental junctures?

What is the link between male and female gender roles and the risks and responsibilities of sexual behaviors?

[What is] the diversity and distribution of sexual values, beliefs, and behaviors within different populations [that may be affected by AIDS] and their meanings for individuals?

What is the range of adolescent sexual behaviors?

What is the impact of [adolescent] peer relations on sexual activity?

What is the actual prevalence and range of experiences of abusive and coercive sexuality in the United States?

What impact do experiences of sexual coercion as a child have on subsequent adult sexual development and behaviors?

Why is the public rhetoric and treatment of sexuality issues so distinct?

How does knowledge produced by research get disseminated and refracted through a political lens?

The importance of these questions is beyond question. But it's a bit as if physicists had issued a report saying that they needed to figure out what light is, and how lenses bend it; one might have hoped for something a bit more specific by now.

The largest survey of American sexual behavior, The Social Organization of Sexuality, has been very sharply criticized by biologist R. C. Lewontin. In designing and conducting their study, the researchers appear to have made some indefensible assumptions about their subjects, leading Lewontin to say, quite defensibly, with some sarcasm:

...Why should anyone lie on a questionnaire that was answered in a face-to-face interview with a total stranger? After all, complete confidentiality was observed. It is frightening to think that social science is in the hands of professionals who are so deaf to human nuance that they believe that people do not lie to themselves about the most freighted aspects of their own lives, and that they have no interest in manipulating the impression that strangers have of them.

Unlike many, however, Lewontin does not indulge in the invalid inference, "Doing X is very difficult; therefore, doing X is impossible." (Add as many "very"s as you like ­ the inference is still invalid.) Instead, he says, wisely and sympathetically,

The social scientist is in a difficult, if not impossible position. On the one hand there is the temptation to see all of society as one's autobiography writ large, surely not the path to general truth. On the other, there is the attempt to be general and objective by pretending that one knows nothing about the experience of being human, forcing the investigator to pretend that people usually know and tell the truth about important issues, when we all know from our own lives how impossible that is. How, then, can there be a "social science"? The answer, surely, is to be less ambitious and stop trying to make sociology into a natural science although it is, indeed, the study of natural objects. There are some things in the world that we will never know and many that we will never know exactly. Each domain of phenomena has its characteristic grain of knowability. Biology is not physics, because organisms are such complex physical objects, and sociology is not biology because human societies are made by self-conscious organisms. . . . (Italics added)

So, although he is a tough critic of some current work in sexology, Lewontin does not conclude that sexology is pseudoscientific, any more than he concludes that biology is pseudoscientific. Because judgments about science and pseudoscience often take (a certain conception of) physics as typical and definitive of science, any attempt to study highly complex systems may seem less scientific ­ but this is just a way of repeating the error in the invalid inference from difficulty to impossibility. Because judgments about sexology are often tainted by attitudes toward sex, it faces additional barriers to investigation that do not bedevil, say, invertebrate zoology or botany. Given that Justice Brennan is right about sex, we have good reason to be more than hopeless about the future progress of sexology, and no good reason to dismiss it as pseudoscience. This is a clear case in which insufficiency of resources has helped to foster an impression of substandard status, thus making it more difficult for researchers to claim the needed resources. In the meantime, people suffer and die.

Chaos and Paradigms

In 1983, a mathematician named Benoit Mandelbrot published the second edition of a beautifully illustrated book, re-entitled The Fractal Geometry of Nature. The book is an extended discussion of mathematical objects with an exceptionally rich structure. The objects were called "fractals" by Mandelbrot, a contraction of "fractional dimensional measure." The book is mathematically interesting, but the excitement it caused extended well beyond mathematics. Mandelbrot himself is an applied mathematician and has worked in many areas of applied mathematics, among them information theory, linguistics, biology, geography, economics, diffusion theory. In each, he found fractals. One of Mandelbrot's favorite trick questions is to ask, "How long is the coast of the eastern seaboard of the U. S.?" Most people will say something like 1,000-2,000 miles, and almost no one says 10 million miles. But both answers are equally plausible: it all depends on the scale of measurement. As you measure more and more finely, the coast "gets longer." Also, you will find that patterns found at coarser scales get repeated at finer scales. This phenomenon of scaling, or self-similarity, is characteristic of many fractals. When it is found, it suggests that a simple law is at work, being applied repeatedly to produce great complexity. The most familiar such patterns are snowflakes.

It has been known for a long time that order and symmetry underlie such crystalline structures. What is somewhat surprising is that the same sort of order appears in apparently disorderly systems. Such systems are called "chaotic," and the branch of mathematics that studies them is called "Chaos." (It used to be called "non-linear dynamics," but the new term is sexier.) It is beginning to seem that there are limits on Chaos, that there are certain types of disorder which can be classified and studied in theory and in the laboratory. A mathematician at University of California at Santa Cruz who has a small lab to study a dripping faucet has found that the faucet may begin dripping at one rate, but then the system changes to oscillate between two rates. When those rates split again, four unstable equilibrium points emerge, then eight, and so on, until the system becomes completely chaotic. This is the period-doubling route to Chaos, and it characterizes many chaotic processes. In 1976, a Los Alamos lab physicist, Mitchell Feigenbaum, was sitting at his desk playing with a desk calculator, fooling around with the equation for a parabola, and feeding the results of one iteration into the next. When he looked at the ratio of rates at which the equation approached certain values, he found a numerical constant showing up again and again. This was mildly surprising, but he at first thought that it was just a peculiarity of the particular equation he was studying. With a mathematician's instinct for generalization, however, he decided to see if the number showed up anywhere else. So he moved to a bigger computer and found very much to his and everyone else's surprise that the same number showed up in many cases of period doubling. Since period doubling as a route to chaos is common to many processes ­ heart attacks, stock market fluctuations, atomic phenomena, biological populations and epidemics, etc. ­ this is a significant result. It places a very stringent limit on how disorderly such processes can be. The numbers he discovered are now called "Feigenbaum numbers" (which are transcendental, like e and ).

[The systems I have been alluding to are usually modeled using differential equations describing continuous, as opposed to discrete processes. But it is possible to model fractal and chaotic systems as discrete processes. If our scale is fine enough, we won't be able to "see" the difference. This is what we do when we solve differential equations on a computer. We use difference equations to get approximate solutions to differential equations.]

I'll describe the amazingly simple rule that generates the most famous fractal: the Mandelbrot set, which has been called the most complex object ever discovered by human beings. It might even be compared in some respects to thinking things.

[WARNING! MATHEMATICAL FORMULAE AHEAD!]

First I need to tell you a bit about complex numbers. A complex number is simply an ordered pair of real numbers: z = (a,b). Call the first coordinate the "real part" of z and the second coordinate the "i-part" of z. We can think of such complex numbers as coordinates in the plane. The set of all complex numbers forms a mathematical set called a field if we define addition and multiplication as follows:

(a,b) + (c,d) = (a + c, b + d)

(a,b) * (c,d) = (ac - bd, ad + bc).

Note that (0,1)*(0,1) = (-1,0). We can define (distance and) magnitude as follows:

|z| = (a^2 + b^2).

We can have functions of complex variables, too. Consider the very simple one defined by

fc(z) = z^2 + c, for c some complex constant, possibly negative.

Imagine that we pick some value for c and that we start iterating. Let z = (0,0) to begin with, plug it in to the equation and then feed the result back into the equation. That gives 0^2 + c = c. And with z = c, fc(z) = c^2 + c. At the next iteration we get (c^2 + c)^2 + c, and so it goes. When the magnitude of the numbers reaches a certain size, the result of iteration begins to grow very quickly, though just how fast it grows depends on the initial choice of c.

The Mandelbrot set is the set of all complex numbers c for which the magnitude of fc(z) = z^2 + c is finite even after indefinitely many iterations. We can represent this set with a black region in the complex plane, using colors from red to violet to represent different rates at which points outside the set "go off to infinity."

[DONE WITH FORMULAE. PHEW.]

That's all there is to it. The result is amazing for its beauty and complexity. You owe it to yourself to take a look at some of the many books that feature pictures of this extraordinary object, and, if possible, to view some of the many videos made to exhibit its beauty and some of its infinite complexity. Only graphical descriptions of the Mandelbrot set will enable you to visually appreciate the fact that it is both deterministic and unpredictable: although each and every point in the graph has its position and color determined with absolute precision and rigidity, the global result is utterly unexpected.

This last feature ­ the paradoxical sounding combination of determinism and unpredictability ­ is a consequence of the key feature of chaotic systems: sensitive dependence on initial conditions. In nonchaotic systems, a very small change in the initial state will result in a correspondingly small change in successive final states. In chaotic systems, even the smallest change in how things start is magnified in ways that can't be anticipated exactly, and the resulting change in the system may be enormous. If a chaotic system changes fast enough and is complex enough, it will outrun even the capacity of the fastest physically possible computer to simulate its operation. Such a system would be unpredictable in a very profound sense: the laws of nature would make it impossible for us to know what it was going to do before it actually did it; as a matter of physical necessity, the most efficient way to find out about the system would be to watch it change.

Because of the prevalence of chaotic systems in nature and in the world human beings have created, the visual beauty of the graphs of chaos, and the tantalizing near-contradictoriness of such systems' basic natures, Chaos theory has received a great deal of attention in the popular media and has spawned a sizeable cottage industry in fractal and chaotic products. James Gleick's Chaos: Making a New Science was on the New York Times best-seller list for many weeks, and many other popularizations have been published in its wake. An episode of NOVA was devoted to the "new paradigm of scientific explanation, Chaos theory."

Some scientists have seen the flurry of public attention as excessive, and there's been some discussion of just how big a change Chaos theory induces in previously well-established scientific perspectives on non-linear systems. Describing Chaos theory as bringing a "new paradigm" tends to heat up the discussion, sometimes to the point of chaos.

The notion of a paradigm was introduced into twentieth-century discussions of science by the historian of science Thomas Kuhn in his famous book, The Structure of Scientific Revolutions. Before Kuhn wrote the book, many scholars of science had shown an unfortunate tendency to view science as a steadily progressive enterprise with a largely stable stock of concepts, standards, and methods. Kuhn emphasized that scientific revolutions sometime occur in which conceptual and methodological upheaval results. One paradigm is discarded and replaced by another. Although Kuhn himself never endorsed the view, some even proposed that science itself is defined by the process of paradigm development and replacement: science and science alone is governed by paradigms. If this is correct, then it might yield a gatekeeper:

Chaos theory is scientific because it is governed by a paradigm

and if, say, astrology, failed to be paradigm-governed it could be dismissed as pseudoscientific.

None of this is very helpful unless we have a very clear idea of what a paradigm is and are sure that the notion is coherent. Soon after The Structure of Scientific Revolutions was published, reviewers began to criticize it for failure on both scores. One of the earliest, most highly critical and influential reviews was by Dudley Shapere. Here is Shapere's selection of Kuhn's key remarks about paradigms:

Paradigms are "universally recognized scientific achievements that for a time provide model problems and solutions to a community of practitioners" (x).

Because a paradigm is "at the start largely a promise of success discoverable in selected and still incomplete examples" (23-24) it is "an object for further articulation and specification under new or more stringent conditions" (23); hence from paradigms "spring particular coherent traditions of scientific research" called "normal science." Normal science consists largely of "mopping-up operations" (24) devoted to actualizing the initial promise of the paradigm "by extending the knowledge of those facts that the paradigm displays as particularly revealing, by increasing the extent of the match between those facts and the paradigm's predictions, and by further articulation of the paradigm itself" (24).

A paradigm provides "a criterion for choosing problems that, while the paradigm is taken for granted, can be assumed to have solutions" (37).

"Scientific revolutions are . . . those non-cumulative developmental episodes in which an older paradigm is replaced in whole or in part by an incompatible new one" (91).

A paradigm is [simply?] "a set of recurrent and quasi-standard illustrations of various theories," and these are "revealed in its textbooks, lectures, and laboratory exercises" (43).

Paradigms, as accepted examples of prevailing scientific practice "include law, theory, application, and instrumentation together" (10).

A paradigm consists of a "strong network of commitments - conceptual, theoretical, instrumental, and methodological" (42) among which are "quasi-metaphysical" ones (41).

A paradigm is, or includes, "some implicit body of intertwined theoretical and methodological belief that permits selection, evaluation, and criticism" (16-17). Such a body of beliefs is never implied by the facts, and so "it must be externally supplied, perhaps by a current metaphysic, by another science, or by personal or historical accident" (17).

"From [paradigms] as models spring particular coherent traditions."

So far, astrology, phrenology and Scientific Creationism seem to be doing very well. But things get murkier.

Most fundamentally, they are not rules, theories or the like, or a mere sum thereof, but something more "global" (43) from which rules, theories, etc., are abstracted, but to which no mere statement of rules or theories, etc., can do justice. So anything that allows science to accomplish anything can be a part of, or somehow involved in, a paradigm.

"Once a first paradigm through which to view nature has been found, there is no such thing as research in the absence of any paradigm" (79).

"There can be no scientifically or empirically neutral system of language or concepts, [so] the proposed construction of alternate tests and theories must proceed from within one or another paradigm-based tradition" (145).

Paradigms are open to "direct inspection" although they cannot in general be formulated adequately (44).

"An apparently arbitrary element . . . is always a formative ingredient" (4) of a paradigm.

A paradigm is "the source of the methods, problem-field, and standards of solution accepted by any mature scientific community at any given time, . . . the reception of a new paradigm often necessitates a redefinition of the corresponding science . . .. And as the problems change, so, often, does the standard that distinguishes a real scientific solution from a mere metaphysical speculation, word game, or mathematical play. The normal-scientific tradition that emerges from a scientific revolution is not only incompatible but often incommensurable with that which has gone before" (102). Thus the paradigm change entails "changes in the standards governing permissible problems, concepts, and explanations" (105). "The differences between successive paradigms are both necessary and irreconcilable" (102).

"The competition between paradigms is not the sort of battle that can be resolved by proofs" (147), but is more like a "conversion experience" (150). In a scientific revolution (paradigm-shift), "What occurred was neither a decline nor a raising of standards, but simply a change demanded by the adoption of a new paradigm" (107). "In these matters, neither truth nor error is at issue" (150). "We may . . . have to relinquish the notion . . . that changes of paradigm carry scientists . . . closer and closer to the truth" (169).

With the notion of paradigm characterized in this way, Kuhn's use of it seems to suggest not just that standards can change in science, but that there really are no standards in science and that any hope of distinguishing between science and pseudoscience had best be abandoned. In the second edition of The Structure of Scientific Revolutions, Kuhn disowns this highly provocative first edition view that almost all his critics took him to be proposing. As modified in the second edition, his views seem to come to no more than rather bland remarks about the social context of science, for example, "scientists often work in groups, sometimes disagree with members of their own research groups, but may sometimes be able to resolve such intra-group disagreements more easily than inter-group disagreements."

To return to Chaos theory, we can fairly say that it offers some surprises and some hope for gaining a better understanding of a turbulent world, but there seems no point in saying that it involves a new paradigm.

Lessons about Gatekeeping

What lessons can we draw from our discussion of four alleged examples of pseudoscience, and over a dozen failed demarcation criteria? There are two sorts of lessons, negative and positive. I'll say first what we have and what we have not established about Scientific Creationism.

With Kitcher's help, it has been shown that evolutionary theory is a much better theory than Scientific Creationism; it has characteristics that any good explanation ought to have, and Scientific Creationism seems to have very little of any of those characteristics. Scientific Creationism is pretty clearly an awful theory, with little of the justifying evidence, predictive success, or explanatory power of evolutionary theory.

By itself, this does not show that evolutionary theory is true and Scientific Creationism false. Scientific Creationists sometimes write as if those views were the only two possible explanations of the relevant phenomena, but we should not join them in their mistake. Although it may be hard to think of a plausible explanation besides evolutionary theory, we haven't proved that evolutionary theory is correct just by showing that it is better.

Nor have we shown that evolutionary theory and religion are incompatible. In fact, we haven't said anything even to suggest that Christianity, in all its forms, is incompatible with evolutionary theory. All we have done is to show that some of the Biblical interpretations of some members of a minority religious group are deficient as scientific explanations of some biological phenomena. Scientific Creationism is just one of many ways of expressing a religious viewpoint and values ­ not the only way. Sympathy with such viewpoints and values should not mislead us into endorsing a view as if it were the only way. Rejecting Scientific Creationism does not mean that nothing that it says is right or worth preserving. It may be possible to preserve parts of the view without buying all of it. Nor does a sense of fairness require that any and every view should be taught in science courses.

Should Scientific Creationism be taught in public school science courses? We haven't settled that question either.

The First Amendment to the U. S. Constitution says in part, "Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof ...." This has been interpreted as placing some restrictions on public school curricula. But we haven't studied the relevant court cases. The language itself rings a bit odd in late twentieth-century ears. The authors of the Constitution did not waste words, so they surely had very good reasons for writing the amendment exactly as they did. Why did they write of an "establishment"? The word's not purely decorative. And their use of "respecting" is somewhat unusual. We know what it is to respect a person (if that's anything like the intended usage), but what does it mean to respect an establishment? And then there the $64,000 question: What is a religion? Suppose, however, that we could figure out exactly what the authors meant. We'd still face another major question in constitutional law: Are we now bound by the originally intended meanings, or is the Constitution better thought of re-interpretable in changed social circumstances? Since we've not addressed any of these jurisprudential questions, we've not settled many issues relevant to deciding whether Scientific Creationism can legally be taught in public school science courses. (The U. S. Supreme Court has not entirely settled this either, in no small part because it can get things wrong and can change its institutional mind. There are some respected constitutional scholars who believe that although the Arkansas and Louisiana "Creation Science" laws were flawed, it is feasible to draft such laws that will pass muster.)

Constitutional and other legal questions aside, there are questions about educational psychology that need to be addressed. A main purpose of teaching theories in elementary and secondary schools is to instruct students about what in general makes for a good explanation. It might be that teaching Scientific Creationism would serve a useful purpose in science courses: it could provide an example of what never to do. Making an example of it in this way ­ a bad example ­ might help students to do better, and to appreciate the richness of evolutionary theory. Scientific Creationists would not view that as a victory, but this is not about pleasing them. On the other hand, teaching Scientific Creationism and evolutionary theory in tandem might overload students, resulting in a diminished appreciation of the latter theory's virtues, and that would be a disaster. My hunch is that which of these two possibilities obtains will depend on features of the teachers and the students in a particular class, and that it'd be a rather complicated matter to sort out the two sorts of situations. But I'd hate for the future of US science education to depend on my hunch. I'd much rather someone did the necessary empirical research so that we can improve our children's science education.

Lessons about Demarcating Science from Pseudoscience

It would have been very nice if we could have had a nice, clear, clean, simple criterion for separating the good stuff from the bad. We have looked at over a dozen such criteria, and they're all rotten, either because they misrepresent science or because they misrepresent the view being assessed, or both. Two things are clear from our examination of Scientific Creationism and other views: (i) the difference between science and pseudoscience is a difference in degree not a sharp difference in kind; and (ii) there is simply no substitute for careful and detailed scrutiny of a theory when its scientific status is in question; sometimes, we must even spend some of our scarce resources on experimental evaluation of the theory. Things are even more complicated when it's not a theory, but a branch of inquiry whose status is in question. Astrology, phrenology, Scientific Creationism, and Chinese acupuncture are theories; unlike them, parapsychology, UFOlogy, sexology, and Chaos theory are not theories, but branches of inquiry defined by the questions that they pose. To show that any of the latter are pseudoscientific, we would have to demonstrate that the questions themselves are not worth asking (or, perhaps, that they have no hope of being answered), and that's generally very difficult to do.

This does not mean that there are no standards in science, that there is no difference between truth and falsehood, between correct and incorrect, between good reasons and bad, etc. There are such standards, and many of them are quite familiar. It is a main job of courses in inductive logic and deductive logic to evaluate and systematize just such standards.

But ­ and this is the most important lesson of our investigation so far ­ science has no corner on the market in high standards. This is such an important, and often ignored, point that I want to restate it in a different way, to reinforce understanding.

There are two independent uses of the word "science" that often get confused in debates on these matters: one is the "list" use: we give a list of areas that we think of as clear examples of science, e.g., physics, chemistry and biology, and the applied sciences based on them; the other is an "approval" use: "science" means whatever accords with the highest cognitive standards. It is important to keep in mind that these are two different uses. Failure to do so has two bad consequences: (a) we may think that what's on the list always meets those standards, and so be led to overvalue it; (b) we may think that only the things on the list meet those high standards. Both (a) and (b) are false, but (b) is the most pernicious. It leads some to think that if it's not physics, etc., then it's garbage. No wonder some religious groups feel threatened. But they should not buy into the errors of their opponents. There is no reason why literary analysis, history, philosophy, and religion ­ to give just a few examples ­ cannot be "scientific" in the approval sense.

Why is this error so common? While I have no deep explanation of this complex psychological and social phenomenon, I'll offer one observation. When we are anxious to draw sharp lines and to find clear differences between two things, we often exaggerate the differences, just to help us get started (and to hit opponents over the head). One way of exaggerating differences is to compare the worst examples of one kind of thing with the best examples of the other. In this case, depending on their initial biases, participants in the debate compare the best science to the worst religion, or the worst science to the best religion. If, for example, one compares the best science to the worst religion, one will be struck by the lack of systematic, empirical investigation in the latter. The picture is different if one compares the worst science to the best religion or the best religion to the best science. Even a stalwart atheist who is utterly devoid of religious sentiment must credit the highly systematic, exquisitely careful collection and evaluation of religious experience that is characteristic of religion at its best. And where else would one seek the essence (if any) of religion? Whatever the cognitive or rhetorical utility of exaggeration, we cannot allow its distortions to deprive us of the truth.

Some of the most vocal opponents of Scientific Creationism are themselves clergy and other deeply religious people. They realize the latter point. They also fear that by setting Scientific Creationism up as a direct competitor to evolutionary theory, religion opens itself up to challenges that it should not have to face. Because, despite the recognition that there are cognitive standards in religion as well, many believe that religion and science are so different that there is really no possibility of any serious conflict between them. We'll need to take a close look at that widely held belief in the second part of the course, when we address the question, What is the difference between science and religion? For now, let us summarize what we have learned so far by quoting an old Shaker saying, "God dwells in the details."

(c)2000 David F. Austin

This page last updated on July 14, 2000