A couple weeks ago, I participated in an online debate at Evolution News & Views with Center for Science & Culture fellow Michael Flannery on the question: “If he were alive today, would evolutionary theory’s co-discoverer, Alfred Russel Wallace, be an intelligent design advocate?” The following is my opening statement in the debate. A link to Flannery’s reply can be found near the end of this page.
The double dangerous game of Whiggish What-if? history is on the table in this debate that inexorably invokes hindsight bias, along the lines of “Was Thomas Jefferson a racist because he had slaves?” Adjudicating historical belief and behavior with modern judicial scales is a fool’s errand that carries but one virtue—enlightenment of the past for correcting current misunderstandings. Thus I shall endeavor to enlighten modern thinkers on the perils of misjudging Alfred Russel Wallace as an Intelligent Design creationist, and at the same time reveal the fundamental flaw in both his evolutionary theory and that of this latest incarnation of creationism.
Wallace’s scientific heresy was first delivered in the April, 1869 issue of The Quarterly Review, in which he outlined what he saw as the failure of natural selection to explain the enlarged human brain (compared to apes), as well as the organs of speech, the hand, and the external form of the body:
In the brain of the lowest savages and, as far as we know, of the prehistoric races, we have an organ…little inferior in size and complexity to that of the highest types…. But the mental requirements of the lowest savages, such as the Australians or the Andaman Islanders, are very little above those of many animals. How then was an organ developed far beyond the needs of its possessor? Natural Selection could only have endowed the savage with a brain a little superior to that of an ape, whereas he actually possesses one but very little inferior to that of the average members of our learned societies.
(Please note the language that, were we to judge the man solely by his descriptors for indigenous peoples, would lead us to label Wallace a racist even though he was in his own time what we would today call a progressive liberal.)
Since natural selection was the only law of nature Wallace knew of to explain the development of these structures, and since he determined that it could not adequately do so, he concluded that “an Overruling Intelligence has watched over the action of those laws, so directing variations and so determining their accumulation, as finally to produce an organization sufficiently perfect to admit of, and even to aid in, the indefinite advancement of our mental and moral nature.”
Natural selection is not prescient—it does not select for needs in the future. Nature did not know we would one day need a big brain in order to contemplate the heavens or compute complex mathematical problems; she merely selected amongst our ancestors those who were best able to survive and leave behind offspring. But since we are capable of such sublime and lofty mental functions, Wallace deduced, clearly natural selection could not have been the originator of a brain big enough to handle them. Thus the need to invoke an “Overruling Intelligence” for this apparent gap in the theory.
Why did Wallace retreat from his own theory of natural selection when it came to the human mind? The answer, in a word, is hyper-selectionism (or adaptationism), in which the current adaptive purpose of a structure or function must be explained by natural selection applied to the past. Birds presently use wings to fly, so if we cannot conceive of how natural selection could incrementally select for fractional wings that were fully functional at each partial stage (called “the problem of incipient stages”) then some other force must have been at work. Darwin answered this criticism by demonstrating how present structures serve a purpose different from the one for which they were originally selected. Partial wings, for example, were not poorly designed flying structures but well designed thermoregulators. Stephen Jay Gould calls this process “exaptation” (ex-adaptation) and uses the Panda’s thumb as his type specimen: it is not a poorly designed thumb but a radial sesamoid (wrist) bone modified by natural selection for stripping leaves off bamboo shoots.
Wallace’s hyperselectionism and adaptationism were outlined more formally in an 1870 paper, “The Limits of Natural Selection as Applied to Man,” in which he admitted up front the danger of proffering a force that is beyond those known to science: “I must confess that this theory has the disadvantage of requiring the intervention of some distinct individual intelligence…. It therefore implies that the great laws which govern the material universe were insufficient for this production, unless we consider…that the controlling action of such higher intelligences is a necessary part of those laws….”
After an extensive analysis of brain size differences between humans and non-human primates, Wallace then considers such abstractions as law, government, science, and even such games as chess (a favorite pastime of his), noting that “savages” lack all such advances. Even more, “Any considerable development of these would, in fact, be useless or even hurtful to him, since they would to some extent interfere with the supremacy of those perceptive and animal faculties on which his very existence often depends, in the severe struggle he has to carry on against nature and his fellow-man. Yet the rudiments of all these powers and feelings undoubtedly exist in him, since one or other of them frequently manifest themselves in exceptional cases, or when some special circumstances call them forth.”
Therefore, he concludes, “the general, moral, and intellectual development of the savage is not less removed from that of civilised man than has been shown to be the case in the one department of mathematics; and from the fact that all the moral and intellectual faculties do occasionally manifest themselves, we may fairly conclude that they are always latent, and that the large brain of the savage man is much beyond his actual requirements in the savage state.” Thus, “A brain one-half larger than that of the gorilla would, according to the evidence before us, fully have sufficed for the limited mental development of the savage; and we must therefore admit that the large brain he actually possesses could never have been solely developed by any of those laws of evolution…. The brain of prehistoric and of savage man seems to me to prove the existence of some power distinct from that which has guided the development of the lower animals through their ever-varying forms of being.”
The middle sections of this lengthy paper review additional human features that Wallace could not conceive of being evolved by natural selection: the distribution of body hair, naked skin, feet and hands, the voice box and speech, the ability to sing, artistic notions of form, color, and composition, mathematical reasoning and geometrical spatial abilities, morality and ethical systems, and especially such concepts as space and time, eternity and infinity. “How were all or any of these faculties first developed, when they could have been of no possible use to man in his early stages of barbarism? How could natural selection, or survival of the fittest in the struggle for existence, at all favour the development of mental powers so entirely removed from the material necessities of savage men, and which even now, with our comparatively high civilisation, are, in their farthest developments, in advance of the age, and appear to have relation rather to the future of the race than to its actual status?”
Modern Intelligent Design creationists generally (with few exceptions) believe that the designer is God. Nowhere in this paper does Wallace invoke God as the overarching intelligence. In a footnote in the second edition of the volume in which this paper was published, in fact, Wallace upbraids those who accused him of such speculations:
Some of my critics seem quite to have misunderstood my meaning in this part of the argument. They have accused me of unnecessarily and unphilosophically appealing to “first causes” in order to get over a difficulty—of believing that “our brains are made by God and our lungs by natural selection;” and that, in point of fact, “man is God’s domestic animal.” … Now, in referring to the origin of man, and its possible determining causes, I have used the words “some other power”—“some intelligent power”—“a superior intelligence”—“a controlling intelligence,” and only in reference to the origin of universal forces and laws have I spoken of the will or power of “one Supreme Intelligence.” These are the only expressions I have used in alluding to the power which I believe has acted in the case of man, and they were purposely chosen to show that I reject the hypothesis of “first causes” for any and every special effect in the universe, except in the same sense that the action of man or of any other intelligent being is a first cause. In using such terms I wished to show plainly that I contemplated the possibility that the development of the essentially human portions of man’s structure and intellect may have been determined by the directing influence of some higher intelligent beings, acting through natural and universal laws.
Clearly Wallace’s heresy had nothing to do with God or any other supernatural force, as these “natural and universal laws” could be fully incorporated into the type of empirical science he practiced. It was not spiritualism, but scientism at work in Wallace’s world-view: “These speculations are usually held to be far beyond the bounds of science; but they appear to me to be more legitimate deductions from the facts of science than those which consist in reducing the whole universe…to matter conceived and defined so as to be philosophically inconceivable.”
In Wallace’s science there is no supernatural. There is only the natural and unexplained phenomenon yet to be incorporated into the natural sciences. That he left no room in his evolutionary theory for exaptations of early structures for later use is no reflection on his ambitions and abilities as a scientist. It was, in fact, one of Wallace’s career goals to be the scientist who brought more of the apparent supernatural into the realm of the natural, and the remainder of his life was devoted to fleshing out the details of a scientism that encompassed so many different issues and controversies that made him a heretic-scientist.
If modern Intelligent Design theorists restricted their visage to only natural causes they would, perchance, be taken more seriously by the scientific community, who at present (myself included) sees this movement as nothing more than another species of the genus Homo creationopithicus.
Read Flannery’s reply to my opening statement and tune into Skepticblog in a couple weeks for my response to him.