I want to consider, in light of fairly new philosophical and scientific research, two long-standing conceptual objections to evolutionary theory: Wallace’s Problem and Darwin’s Doubt.
It is well-recognized that Wallace saw the need for some supernatural intelligence in explaining human evolution, in contrast to Darwin’s naturalistic speculations in Descent of Man. What is less recognized is that Wallace was, in an important sense, right. He squarely faced the problem, “can natural selection alone account for the unique cognitive abilities of human beings, such as abstract thought, self-consciousness, radical reshaping of the environment (e.g. clothing, building), collective self-governance by ethical norms, and the symbolic activities of art, religion, philosophy, mathematics, logic, and science?” Whereas Darwin thought there was continuity between humans and non-human animals, his evidence is primarily amount emotional displays, rather than the genuinely cognitive discontinuity.
A closely related problem, however, was squarely faced by Darwin: the question, nicely phrased in his famous letter to Asa Gray, as to whether it is plausible to think that natural selection can have equipped a creature with a capacity for arriving at any objective truths about the world. (It is not often noted that in that letter, Darwin says that he believes in an intelligent creator — what is in doubt is whether natural selection gives him reasons to trust in his cognitive abilities.)
These two questions, Wallace’s Problem and Darwin’s Doubt, are two sides of the same coin: if natural selection (along with other biological processes) cannot account for the uniquely human ability to grasp objective truths about reality, then we must either reject naturalism (as Wallace did) or question our ability to grasp objective truths about reality (as Darwin did).
Call this the Cognitive Dilemma for Naturalism. Can it be solved? If so, how?