Norman Macbeth's concise yet lucid survey of the subject, Darwin Retried, began when he used some idle time while convalescing in Switzerland to read a volume of essays commemorating the 1959 centenary of Origin's publication. His conclusion after the several years of further research that his first impressions prompted was that "in brief, classical Darwinism is no longer considered valid by qualified biologists." 19 They just weren't telling the public. One of the most startling things Macbeth discovered was that while natural selection figured almost as a required credo on all the lists of factors cited in the experts' writings as contributing to evolution, the importance they assigned to it ranged from its being "the only effective agency," according to Julian Huxley, to virtually irrelevant in the opinions of others—even though it was just this that formed the substantive part of the title to Darwin's book.
The reason for this backing off from what started out as the hallmark of the theory is that while mechanisms showing the effectiveness of natural selection can be readily constructed in imaginative speculations, any actual example of the process in action in the real world proceeds invisibly. Early Darwinians were carried away into concluding that every aspect of an animal down to the number of its spots or bristles was shaped by natural selection and thus was "adaptive," i.e., relevant to survival. Purporting to explain how the selective value of a particular, possibly trivial characteristic arose became something of a game among the enthusiasts, leading to such wild flights of just-so-story fancy and absurd reasoning that the more serious-minded gave up trying to account for the specifics, which were observable, while retaining undiminished faith in the principle, which wasn't.
Put another way, it was claimed that natural selection worked because the results said to follow from it were evident all around. But this is the logical fallacy of saying that because A implies B, B must imply A. If it rained this morning, the grass will necessarily be wet. But finding the grass wet doesn't mean necessarily that it rained. The sprinklers may have been on; the kids could have been playing with the hose; a passing UFO might have vented a coolant tank, and so on. Confirming the deductions from a theory only lends support to the theory when they can be shown to follow from it uniquely, as opposed to being equally consistent with rival theories. If only naturalistic explanations are allowed by the ground rules, then that condition is satisfied automatically since no explanation other than natural selection, even with its problems, has been offered that comes even close to being plausible. But being awarded the prize through default after all other contenders have been disqualified is hardly an impressive performance.
The Darwinists' reaction to this entanglement was to move away from the original ideas of struggle and survival, and redefine evolution in terms of visible consequences, namely that animals with certain features did well and increased in numbers, others declined, while yet others again seemed to stay the same. Although perpetuating the same shaky logic, this had the benefit of making the theory synonymous with facts that couldn't be denied, without the burden of explaining exactly how and why they came about, which had been the original intention. In the general retreat from what Darwinism used to mean, "evolution" became a matter of the mathematics of gene flows and population dynamics, in a word differential reproduction, in the course of which "natural selection" takes on the broader meaning of being simply anything that brings it about. 20 So evolution is defined as change brought about by natural selection, where natural selection, through a massive circularity, arrives back at being anything that produces change. What Macbeth finds staggering in this is the ease with which the leaders of the field not only accept such tautologies blithely as inherent in their belief system, but are unable to see anything improper in tautological reasoning or the meaninglessness of any conclusions drawn from it. 21
A consequence of such illogic is that simple facts which practically define themselves become celebrated as profound revelations of great explanatory power. Take as an example the case of the British peppered moth, cited in virtually all the textbooks as a perfect demonstration of "industrial melanism" and praised excitedly as living proof of evolution in action before our eyes. In summary, the standard version of the story describes a species of moth found in the British Midlands that were predominantly light-colored in earlier times but underwent a population shift in which a dark strain became dominant when the industrial revolution arrived and tree trunks in the moths' habitat were darkened by smoke and air pollution. Then, when cleaner air resulted from the changes and legislation in modern times and the trees lightened again, the moth population reverted to its previous balance. The explanation given is that the moths depend on their coloring as camouflage to protect them from predatory birds. When the tree barks were light, the lighter-colored variety of moths was favored, with darker barks the darker moths did better, and the changing conditions were faithfully mirrored in the population statistics. Indeed, all exactly in keeping with the expectations of "evolution" as now understood.
The reality, however, is apparently more complicated. Research has shown that in at least some localities the darkening of the moths precedes that of the tree barks, suggesting that some common factor—maybe a chemical change in the air—affects both of them. Further, it turns out that the moths don't normally rest on the trunks in daylight in the way textbook pictures show, and in conditions not artificially contrived for experiments, birds in daylight are not a major influence. The pictures were faked by gluing dead moths to tree trunks. 22
But even if the facts were as presented, what would it all add up to, really? Light moths do better against a light background, whereas dark moths do better against a dark background. This is the Earth-shattering outcome after a century and a half of intensive work by some of the best-known names in science developing a theory that changed the world? Both light strains and dark strains of moth were already present from the beginning. Nothing changed or mutated; nothing genetically new came into existence. If we're told that of a hundred soldiers sent into a jungle wearing jungle camouflage garb along with a hundred in arctic whites, more of the former were still around a week later, are we supposed to conclude that one kind "evolved" into another, or that anything happened that wouldn't have been obvious to common sense?
If that's what we're told "evolution" in the now-accepted use of the word means, then so be it. But now we'll need a different word to explain how moths came into existence in the first place. Yet along with such examples as Archaeopteryx and the horse series, the peppered moth is offered as proof that sets the theory on such incontestable grounds that to question it is evidence of being dim-witted or malicious. While other sciences have progressed from sailing clippers to spaceships, Morse telegraph to satellite nets, steam engines to nuclear reactors, these constitute the best evidence that can be mustered after a hundred and fifty years.