The Three Failures of Creationism. Walter Fitch
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known predators of these moths, and it was soon suggested that the increase of dark moths was a matter of camouflage. When the bark of trees was black, dark moths were difficult for the birds to see, but when the bark of trees was whitish, peppered moths were the variant that were difficult to see and thus their chances of survival were enhanced. The positive correlation between the blackness of the trees and the frequency of dark moths supports the proposition of natural selection going on before your eyes. Kettlewell illustrated the camouflage by pinning a peppered and a dark moth side by side on a dark tree trunk and also a similar pair on a light-colored tree. It was astonishing how well the dark moths blended in with the blackened trunk, and equally astonishing how the peppered moths blended in with the light-colored trunk.
But things are not quite as simple as they may at first appear. The Kettlewell study was incomplete in that it failed to properly consider other possible factors, such as migration of moths from surrounding areas that could have overwhelmed the influence of selection. The Kettlewell study also gave undue emphasis to moths resting on tree trunks and failed to consider that birds see ultraviolet light much better than humans and thus might have been able to detect moths that are well camouflaged to human eyes. There are unanswered questions, but the evidence for differential survival in agreement with the selection hypothesis is basically sound, despite the incompleteness of the Kettlewell study.
Wells published a rejoinder to criticisms raised by Padian and Gishlick—criticisms that included pejorative phrases like “notorious peppered moth experiments,” “staged photos of moths on tree trunks,” and “the statistic is bogus” (Emphases mine.) The statistic arises from the observation of forty-seven peppered moths observed resting in the wild, of which twelve were resting on a tree trunk, giving 12/47 = 0.225 of the resting peppered moths located on tree trunks. This was hardly the critical measurement of the study, but it can be said to demonstrate the assertion that peppered moths do rest, in sizable numbers, on tree trunks. That is important, not bogus. In conclusion, loaded words should not be used to attempt to sway your audience.
4. Repetition. “Testing Darwinism by the molecular evidence has never been attempted…. The true scientific question—Does the molecular evidence as a whole tend to confirm Darwinism when evaluated without Darwinist bias?—has never been asked.” Repetition is a form of emphasis present in the two phrases “has never been attempted” and “has never been asked.” Moreover, “Darwinist bias” would be unloaded were it altered to “the Darwinist view.”
F. OTHER TERMS RELEVANT IN LOGICAL ANALYSIS
1. Bias: Any assumption, often unrecognized, that tends to cause the experiment to produce inaccurate answers, pushing the results in one direction. (See objectivity and subjectivity below.)
2. Objectivity: A scientist's goal, reflecting the scientist's attempt to see what is there in his experiments rather than what he hopes, believes, or expects is there. It is the overcoming of one's personal biases or inclinations. This is something that is often difficult to achieve. A common phrase is “If I hadn't seen it, I wouldn't have believed it.” This typifies the nature of objectivity. A different humorous phrase, also typifying objectivity, is “If I hadn't believed it I wouldn't have seen it.” Shakespeare seems to have recognized the problem:
HAMLET: Do you see yonder cloud that's almost in shape of a camel?
POLONIUS: By the mass, and ‘tis like a camel, indeed.
HAMLET: Methinks it is like a weasel.
POLONIUS: It is backed like a weasel.
HAMLET: Or like a whale?
POLONIUS: Very like a whale.
Wishful thinking can often lead us to accept “evidence” that would be rejected by a more objective observer. For example, a primitive human called “Nebraska Man” was once thought to have existed, based on the evidence of a tooth. It was found later that the tooth was not from a human but from an extinct peccary (a piglike hoofed mammal), and had been misidentified as being primitive human. Other examples include the “Paluxy Event” and the “Piltdown Affair.” (See the discussion in sections I and J of chapter 4.) In a more famous example, Martin Fleish-mann and Stanley Pons claimed to have produced “cold fusion” in 1989—but this claim has not been accepted by the scientific community. A case of wishful thinking? In science, it is best to proceed with a good dose of humility.
3. Subjectivity: The misreading of evidence because of personal beliefs. (See bias and objectivity above). Problems associated with bias, (lack of) objectivity, and subjectivity are common to evolutionists and creationists alike. But the two groups typically do not respond in the same manner.
Suppose there is disagreement over two proposed dates for the age of some event or artifact. The evolutionist, understanding the requirements of the scientific method, will ask whether his determination of the dating is repeatable on another sample from the same geographic site. The creationist, on the other hand, doesn't have much interest in repeatability except for its hoped-for conclusions. Then the lack of scientific repeatability is, for the creationist, evidence that the science is wrong and creationism is right. Of course, in the worst case for the scientist, both dates are quite wrong, whereas in the best case for the scientist, both dates are correct but with larger-than-hoped-for error bars. An extreme example of this sort is the date for the Earth's origin.
4. Relevance: the appropriateness of an argument for the question being asked.
5. Moot: no longer relevant. For example, the question “Did any dinosaurs survive their great extinction at the end of the Cretaceous 65 million years ago?” would become moot if a fossil dinosaur were to be found that dates to more recently than 65 M.Y.A.
6. Implication: a proper conclusion, given acceptance of the prior assertions (the premises). Whenever it is impossible for A to be true without B also being true, it is said that A strictly implies B. Although the word entails is sometimes used as a synonym for implies, some logicians (notably Alan Ross Anderson and Nuel D. Belnap) have argued that for A to entail B, not only must it be impossible for A to be true without B being true, but there must be some relevance between the truth of A and the truth of B. For example, a contradiction implies the truth of any proposition whatsoever: “Wolves eat meat and wolves do not eat meat” logically implies “The Earth was created six thousand years ago”; yet it entails only those propositions that are relevant (e.g., “Wolves eat sheep”).
7. Invalid: not having the proper structure of a syllogistic argument. When the conclusion does not follow from the premises, the syllogism is said to be invalid. Even if the conclusion is true, and even if it is an observable fact, if the structure is not proper, the logic is invalid. It is possible to have a true conclusion in an invalid syllogism. The conclusion may be true, but since it does not follow from the premises, the syllogism is invalid.
CHAPTER TWO
The Basics
What is “basic” to the understanding of creationism and evolution? This chapter discusses some of the categories of knowledge and belief, and examines areas of knowledge and information.
A. HOW DO I KNOW ANYTHING?
I suggest seven ways of knowing, not all of which are equally dependable. Examining these ways can be critical in deciding the logic or correctness of a conclusion.
1. Experience is intended to cover the effects of a lifetime of living in the world and learning that if we're hungry and cry, mother will give us milk; if we stand in the rain, we're likely to get wet. Every time we throw our toy out of the crib, it falls on the floor and we begin to learn about gravity and balance. Through the use of induction (reasoning from specific facts to general rules), we begin to formulate laws that seem to us to govern events in our world. Our experiences are formed through our perceptual senses: seeing, hearing, touching, smelling, and tasting. Unfortunately, our perceptions are fallible. The philosopher