"Scientific" creationists have an advantage when they debate a scientist defending evolution. Scientists who remain true to their calling must not only persuade their audience, they must also present the scientific facts fairly according to the canons of scientific discourse. Creationists, on the other hand, labor under no such constraint; they reject much of the scientific method and its associated mode of argument and hence don't have to let that get in the way when they try to persuade an audience.
Scientists must worry about a dilemma when they simplify the scientific facts in order to present them to a lay audience. While they want the facts to be comprehensible to the lay person, not wishing to lose their audience with a number of qualifications which, though important, are difficult for a nonspecialist to grasp, the scientists don't want to simplify the issues to the point that false statements are made. This dilemma provides the creationist with a powerful debating advantage. The creationist knows that his or her dogmatic assertions will appear to the lay audience as straightforward, no-nonsense presentations of the facts; in contrast, the scientific opponent will appear obfuscating and evasive. The lay person is simply not used to people who carefully qualify their remarks. Just about the only context in which the lay person may encounter such careful use of language is when they observe politicians attempting to weasel out of taking a definite stand on an issue; and hence, they become cynical about anyone who presents so many qualifications.
Furthermore, the smartest of the creationists are acquainted sufficiently with the scientific literature to be able to catch up a scientist who presents a simple version of the facts without qualifications. The creationist can point out the technical caveats, thereby making it look like he or she knows more than the scientist or like the scientist is trying to hide something embarrassing to the evolution position. The scientist has no similar maneuver available, since the creationist position is entirely lacking in subtlety. There are no qualifications that need to be worried about; thus, the scientist cannot tie the creationist up with such subtleties.
The scientist can, however, point out the blatant contradictions that are readily apparent in the creationist position. But, if the audience cannot see these absurdities on the surface, it will do the scientist no good to dig out more absurdities that lurk deeper.
Frederick Edwords (1982) has made a suggestion that will help with this problem to a certain extent. If the debate is confined to a narrower topic—such as the evidence from paleontology for evolution or creation rather than all the scientific evidence for evolution or creation—the creationist can be criticized for bringing up irrelevancies. Also, the scientist will then have the opportunity to deal with particular points in more detail. When a proper debate format is used, the issue ought to be "resolved that paleontology provides evidence for creationism," rather than "for evolution," because then the onus of providing proof is on the creationist instead of the scientist. Organizing a debate this way would be an answer to the perennial problem of getting the creationist to state his or her position and preempt any absurd attacks on evolution.
This strategy is not foolproof, however; it doesn't prevent the creationist from running all over the map instead of sticking to the issue. It merely means that the creationist will likely lose the debate—not that there is a correlation between the evolution side winning academic debates and creationists changing their minds.
Creationist Misuse of Language
There is a further weapon in the creationists' arsenal which must be dealt with. Creationists specialize in using words in a manner calculated to promote misunderstanding and to confuse the issues. And they often manage this so thoroughly that, when a scientist introduces facts into the discussion, they become lost in a morass of nonsense.
Often creationists play upon emotive connotations which are not part of the meaning of a scientific term but which are part of the lay person's understanding of it. A case in point is the term materialism. As understood by scientists, it has a technical meaning quite unrelated to its common meaning, which is roughly synonymous to "money-grubbing."
But sometimes it is not an emotive appeal that the creationist is after. Often he or she will simply trade on ambiguities that promote misunderstanding, thus preventing the scientist from getting his or her point across. The scientist faces two difficulties here. First, the more he or she is used to dealing with these technical terms in his or her own field, the less likely he or she is to think of the "ordinary" meanings of these terms and, thus, will not realize how the audience is misinterpreting his or her remarks. This would not, by itself, be a serious problem for the scientist who primarily lectures to undergraduates and may be used to un-intentional misunderstandings caused by these ambiguities. But , the second difficulty arises when a scientist is used to dealing with honest academics who are trying to understand a position; he or she is less likely to know how to deal with the charlatan who is purposely trying to promote misunderstanding.
The major mistake often made by scientists when faced with such an opponent is that the scientists think they do not need to deal with this verbal sleight-of-hand directly. Instead, they concentrate, on correcting the factual errors made by the creationist, without realizing that the audience is not in a position to see what the error is, and why it is so important, until the conceptual confusions have been resolved. One reason the scientist does not deal directly with the misuse of terms is the wish to not appear pedantic in front of a lay audience. This is an important consideration, but sometimes it is better to risk sounding pedantic than be systematically misunderstood.
In what follows, I shall discuss six of the terms with which creationists most often play fast and loose: theory, fact, chance, cause, design, and purpose. I will attempt to explain how creationists use these ambiguities to advance their cause. I leave it to the skilled debator to find a way of explaining these points in a manner that will not lose a lay audience.
Theory Versus Fact
Creationists have been so successful at muddying the waters with the terms theory and fact because both words are ambiguous. Scientists wish to maintain that the theory of evolution is both a fact and a theory; but given the ordinary meanings of these terms, it is extraordinarily difficult to clarify this point. The problem arises because in one meaning of theory and one meaning of fact these terms are contrasted with each other. But according to the other meanings of theory and fact, these terms can both be applied to the same statement.
Perhaps it is easiest to see how these different senses of the two terms relate to each other if we display them in the form of a table. In the first column of Table 1, I show the two different senses of theory, and in the second column, the two different senses of fact. The meaning of fact which appears beside the term theory on each row is the sense in which theory is contrasted with fact. Note the words in boldface at the beginning of each definition. If we use these terms, we can help eliminate the ambiguity that the creationists have been exploiting.
Now examine the two concepts in row A. Scientists claim that the theory of evolution is a scientific fact as opposed to a mere hypothesis. That is, the theory of evolution has been confirmed to the same degree that any scientific fact has been confirmed. This is not to say that it is impossible for the theory of evolution to be falsified. It is just that is has not been to date and, given the evidence in its favor, is unlikely to ever be falsified. At any rate, the arguments propounded to date by the creationists do not give us any reason to doubt its truth.
On the other hand, scientists rightly insist that the theory of evolution is a theory in sense B, as opposed to a particular fact. It is because it is a theory in sense B that the theory of evolution is so important for the teaching of biology—and why the creationist opposition to it constitutes such a threat to the teaching of science. Without the theory of evolution to provide coherence and order to the particular facts of biology, learning biology would have scarcely more value than attempting to memorize the telephone directory. Theories have a special status in science because of their ability to allow us to explain the particular facts of a discipline and because they sometimes aid us in the discovery of new facts. One way of seeing the importance of the theory of evolution to biology is to compare modern biology with its "creation science" alternative; creation science simply lacks any unifying theory. That is precisely why it is so jejune.
Theory of Evolution Versus Theories About the Mechanisms of Evolution
There is yet another confusion over the concept of theory that the creationist will exploit if given the chance. This confusion results from ignoring the distinction between the theory of evolution per se and various theories about the mechanisms of evolution. The Oxford English Dictionary defines evolution as "the origin of species of animals or plants, as conceived by those who attribute it to a process of development from earlier forms, and not to a process of 'special' creation." Of course, the defender of evolution wants to do more than simply cite this definition; the point is to present the evidence for it, and this involves discussion of theories of how evolution might have taken place. But care must be taken to ensure that the discussion does not slide, without the audience being aware of it, from a discussion of evolution per se into a straw man caricature of a theory of the mechanisms of evolution. No one in their right mind would defend the latter, but the creationist will try to pass it off as the view of Darwin and the view defended by modern scientists.
As soon as the scientist points out some of the various alternative theories of the mechanisms of evolution—from Lamarck to Lysenko to Darwin to Stephen Jay Gould—the creationist has a new ploy. He or she will attempt to leave the impression that each of these theories of mechanisms are equally plausible yet inconsistent with each other, thus "canceling each other out"—that the probability of any one of them being true cannot be very high if it is no more probable than any of the alternatives.
The first reply to this gambit is to point out that it is not true that the rival theories of the mechanisms of evolution are equally probable, nor that they are inconsistent with each other in the way the creationist would have the general public believe. Many proposed mechanisms of evolution have been falsified—for example, those of Lamarck and Lysenko. The theories which remain are few in number and incomplete (the latter, a point which proponents of these theories are the first to make). Because they are incomplete, we are not in a position to assert that they are inconsistent with each other. As new evidence forces modification of these theories, the possibility remains that this evidence will render probable some synthesis of rival theories which will prove consistent.
The second reply to the creationists' gambit—and perhaps most important—is to point out that, just because at present we are not in a position to know which theory of the mechanisms of evolution is correct does not mean that the theory of evolution must be rejected. The fact remains that we have a small number of theories of mechanisms which are plausible in their own right and—a point that cannot be overemphasized—far more plausible than the creationist or any other alternative.
One of the advantages of drawing a distinction between these two is that it allows the defender of evolution to show why the creationist debating strategy of attempting to argue for creationism by arguing against particular theories of the mechanisms of evolution is so barren. It assumes that creationism and the particular theory of mechanisms are contradictories—that is, that the truth of one entails the falsity of the other, and the falsity of one entails the truth of the other. In reality, they are only contraries—that is, they cannot both be true together, but they could be false together. Thus, even if the creationist could show that a particular theory of the mechanisms of evolution is false, that would do nothing to demonstrate the truth of creationism. Creationism could be false as well and would be if some other theory of mechanisms which the creationist has not examined is true.
Creationism and the theory of evolution are not contradictories either. They also are contraries. Both could be false if some other creation myth of some other religion were true or if Fred Hoyle is right in thinking that we are the descendants of spacemen or if the real scientific creationists who preceded Darwin, who postulated a series of creations in order to account for the fossil evidence available at the time, turned out to be right after all. The creationists do not consider all of these other alternatives. They do not even consider the theory of evolution but, rather, a straw man. And even if they were to consider each of these in turn and provided sufficient reason for dismissing them, this would not make creationism any more probable than it is—and they are at the mercy of the next theory that will be devised. Until they are prepared to provide arguments for their own theory, we cannot take them seriously as scientists. Unfortunately, they are such dangerous pseudoscientists that we cannot afford to take their efforts lightly.
Chance Versus Cause or Design
Creationists play the same game with chance, cause, and design that they play with theory. Again we find the term chance mistakenly opposed to two sets of terms. And if creationists are allowed, like Humpty Dumpty, to use words any way they wish, the argument will fall apart. Of the leading books defending evolution against scientific creationism, Futuyma (1983:132-147, 184) is perhaps most succinct at sorting out the nonsense generated by creationist misuse of these terms.
Chance, as used in discussions of evolution, is an epistemic term; that is, it refers to our degree of knowledge about which of several possible outcomes might occur in a given situation. We invoke the concept of chance when we lack sufficient knowledge to provide a causal explanation of which outcome will occur and, thus, are forced to predict the outcome on the basis of probabilities. To say that a given outcome occurred by chance is not to rule out a cause for it; it merely means that we are not aware of the correct causal explanation. Nor does it rule out a particular type of causal explanation—one having to do with human (or a god's) design or purpose. You may run into your friend at the supermarket by chance, but this does not mean that you or your friend had no purposes that explain your both being there; it simply means that whatever purposes you had did not include meeting the other person. Or if you are unaware that a pair of dice is fixed, you may assume that the chances of them coming up twelve are one in thirty-six, when in fact the dice are designed to display twelve more frequently. Thus, there is no reason to rule out purpose or design when talking about chance.
But let us look at a situation that closely parallels the position scientists are in when they discuss evolution. You meet your friend at the supermarket on purpose, but a third party is not aware of that purpose, although he is aware of some of the other facts which are relevant to explaining your behavior. The information neither rules out nor entails that you have this purpose in mind. Thus, given the information that this person had, he could not predict that you will meet your friend—or that you will not. It would be a mistake for him to claim that the evidence that he does have can settle the question. But this is not to say that he is in a position to deny that you have a purpose or that you will meet your friend. This is the position that a scientist dealing with the scientific information is in with respect to the question of a god's design or purpose behind evolution. The scientific evidence by itself neither entails nor rules out any information about a god's purpose behind evolution. The scientist may have religious beliefs which lead him or her to believe that there is a purpose behind evolution. But it would be a mistake for him or her to claim that the scientific evidence entails his or hers religious speculations.
Assuming that creationists do not succeed in their efforts to destroy science, our knowledge will increase and our reliance upon probabilistic arguments will diminish. However, given our present knowledge, the use of probabilistic arguments provides the creationists with a goldmine of numbers to fiddle with in a scientific manner and bamboozle those who stand in awe of mathematics but do not understand it. The creationists have had the greatest success in this endeavor in arguing that the theory of evolution ought to be rejected because it assigns an absurdly low probability to life forming on earth. Typical of these arguments is Gish (1981) who quotes the information theorist H. J. Morowitz as claiming that the probability of matter arranging itself into a bacterium, without divine intervention, is 101011 or one chance in one followed by one hundred billion zeroes. In the fashion typical of the pseudoscientist, Gish provides us with no information on the background conditions assumed for this calculation.
Aside from calling this calculation into question, we should point out that, even with a few more zeroes tacked on for good measure, this statement by itself does nothing to refute evolution. Three further conditions must hold before this probability estimate can be used to doubt the theory of evolution: first, there must be a rival theory that explains the occurrence of life at least as well as evolution; and second, that theory must entail a higher probability of life occurring than evolution predicts. Creationism fails both these criteria, because it does not explain anything at all about the way life in fact originated, as opposed to the myriad of other possibilities. It cannot assign a probability to that event or series of events. The third, and most important, condition is that we must have independent reasons for thinking that life had a higher probability of originating than the theory of evolution assigns to it. It is simply a fact that some events occur very infrequently; thus, the correct explanation of an infrequent event should predict that it will occur infrequently.
Perhaps an analogy might help. The odds of your getting the last hand that you got in bridge, whatever it was, were one in 635,013,559,600. Does that give you reason to reject the hypothesis that the deck was randomly shuffled and instead to accept the hypothesis that the deck was stacked? Not at all. All that follows is that the world's bridge players are likely to wait a long time before seeing that particular hand again. Now, if you happened to get all thirteen spades in your last hand, you would have reason to suspect some skullduggery, but not merely because this hand is so rare. It is, in fact, no more (or less) rare than any other hand. What gives you reason to be suspicious is the independent evidence you have about your fellow players' intentions and their ability to stack the deck. Only if this independent evidence gives you reason to assign a higher probability to the stacked deck hypothesis (rather than the random shuffle hypothesis) do you have reason to prefer the former to the latter. Of course, you do have independent reason to think that your friends would want to surprise you with thirteen spades—but very little reason to think that they would arrange for you to get a perfectly unremarkable hand. It is because of this independent evidence that cheating is a better hypothesis in the one situation than in the other.
The same point applies to the creation-evolution debate: unless the creationist is allowed to beg the question by assuming that God had some special design for the earth to be exactly as it is, the odds against this particular outcome occurring are irrelevant, even if they do give us reason to reflect upon how lucky we are to be here to raise these questions.
But the questions about what would have become of us if evolution had taken a different course—whether or not we would have been here—are not the province of scientists or even religionists, until they first get the help of philosophers. The first problem that needs to be settled is who, if anyone, answers to the word we in that question. If evolution had taken a different path, such that the creatures which resulted from it were radically different from the way we turned out, it is difficult to know to whom the question would refer. As the old response to the man who wishes he had never been born goes: 'Ah, but who should be so lucky? Not one man in a thousand!"
This, then, is my analysis of creationist misuse of key terms they bring into the debate. Only by a forthright exposure of such rhetorical abuse of language can an audience acquire a clear idea of the real issues and thereby come to better appreciate the contribution of the theory of evolution to our understanding of life.