It was some time ago when Thomas Nagel's book Mind & Cosmos: Why the Materialist Neo-Darwinian Conception of Nature is Almost Certainly False came out, to a spate of vitriol from the Neo-Darwinists, ironic since Nagel is an atheist and also a Darwinist. I finally had the time to read it, and it was illuminating if only to show the philosophical bankruptcy of the naturalistic Neo-Darwinian synthesis (not that I was convinced otherwise prior to reading that).
Nagel's thesis is very simple: The materialist Neo-Darwinian view of the world does not seem able to account for the "immaterial" realities of Consciousness, Cognition and Value. Nagel is an atheist, and does not reject Darwinism at all. His only "crime" was to suggest that Darwinism is not the be all and end all of everything and cannot adequately account for the other aspects of reality. Nagel does not reject any developmental hypothesis for these realities, only that such only explains the development and use of physical faculties, not the development of the subjective states themselves.
On the issue of Consciousness, Nagel deals with the issue of subjective consciousness, i.e. the fact that organisms have subjective consciousness of themselves. Evolution could "in principle provide the framework for a physical explanation of the appearance of behaviorally complex animal organisms with central nervous systems" (p. 44), but to link this with subjective consciousness is a bare assertion. As Nagel states:
It is not an explanation to say just that the physical process of evolution has resulted in creatures with eyes, ears, central nervous systems, and so forth, and it is simply a brute fact of nature that such creatures are conscious in the familiar ways. Merely to identify a cause is not to provide a significant explanation, without some understanding of why the cause produces the effect. The claim I want to defend is that, since the conscious character of these organisms is one of their most important features, the explanation of the coming into existence of such creatures must include an explanation of the appearance of consciousness. That cannot be a separate question. An account of their biological evolution must explain the appearance of conscious organisms as such. (p. 45)
After exploring various theories, Nagel spoke in passing of substance dualism but passed it over in favor of some form of property dualism as a preferred model. Nagel after all is an atheist, despite his aversion to materialism. While Nagel does not exactly settle on any one theory, he proposes some form of panpsychism as something preferable. As he writes:
But since conscious organisms are not compose of a special kind of stuff, but can be constructed, apparently, from any of the matter in the universe, suitably arranged, it follows that this monism will be universal. Everything, living or not, is constituted from elements having a nature that is both physical and nonphysical — that is, capable of combining into mental wholes. So this reductive account can also be described as a form of panpsychism: all the elements of the physical world are also mental. (p. 57)
A comprehensive reductive conception is favored by the belief that the propensity for the development of organisms with a subjective point of view must have been there from the beginning, just as the propensity for the formation of atoms, molecules, galaxies, and organic compounds must have been there from the beginning, in consequence of the already existing properties of the fundamental particles (p. 61)
In other words, in order to explain consciousness without invoking something separate from matter (e.g. spirit), matter itself must become "spiritual" in the sense that it possess within itself the capability of creating beings possessing subjective consciousness. Materialism is rejected for some version of spiritual-matter emergentism.
The second reality Nagel deals with is that of Cognition. Here, the problems go even deeper than that of consciousness. The problem cognition poses to materialism has two aspects, the first has to do with "the likelihood that the process of natural selection should have generated creatures with the capacity to discover by reason the truth about a reality that extends vastly beyond the initial appearances" (p. 74), and the second is the "difficulty of understanding naturalistically the faculty of reason" (p. 74). The first aspect comes to the fore when the naturalistic theory behind cognition is looped in on itself, which gives rise to the strange notion that our theory of evolution is itself anti-realist, since notions of reality have no objective ground but are rather formed through the random process of evolution. Such is of course unacceptable for any naturalist. Nagel muses about the possibility of some function of a Kantian categorical imperative as the backdrop and evolutionary pressure for the discovery of some form of "objectivity," which he admits is rather far-fetched. (p. 78) Yet even admitting that, the second aspect of the problem rears its ugly head. Instead of merely looping the naturalistic theory upon itself, this loops theories and cognition in general upon itself. The concept of second-degree reasoning (thinking about thinking) is a big problem because how does one explain the assumed objectivity in such meta-reasoning? As Nagel states:
...whenever we take such a reasonable detached attitude toward our innate dispositions, we are implicitly engaged in a form of thought to which we do not at the same time take that detached attitude. When we rely on systems of measurement to correct perception, ... we take ourselves to be responding to systematic reasons which in themselves justify our conclusions, and which do not get their authority from their biological origins. ...
...in a case of reasoning, if it is basic enough, the only thing to think is that I have grasped the truth directly. I cannot pull back from a logical inference and reconfirm it with the reflection that the reality of my logical thought process is consistent with the hypothesis that evolution has selected them for accuracy. ... It is not possible to think, "Reliance on my reason, including my reliance on this very judgment, is reasonable because it is consistent with its having an evolutionary explanation. Therefore, any evolutionary account of the place of reason presupposes reason's validity and cannot confirm it without circularity. (pp. 79-81)
Abstract reasoning is the bane of naturalistic explanations of cognition, because they do not confer any selective advantage to an organism. Meta-reasoning is the abstract of abstract reasoning, reasoning about reasoning, and such cannot be explained naturalistically at all. How could random molecules come up with not just a thinking individual, but an individual that can theorize about thinking itself presupposing objective rules of reasoning while doing so thinking about thinking. To be sure, evolution could conceivably "explain" how those faculties develop, but historical development is insufficient as in the prior case of consciousness. An explanation of "how" is not an answer to "why."
As in the previous section dealing with consciousness, Nagel acknowledges the theists have a simple and workable answer. Nevertheless, he explicitly states his bias against that view even though it does solve all the problems that he is raising for naturalism. As he writes, "My preference for an immanent, natural explanation is congruent with my atheism" (p. 95). Thus, in dealing with this issue, Nagel does accept an emerging constitutive explanation for how rationality could be, but supplements it with a naturalistic teleological principle for its historical emergence as something objective. This principle says that "in addition to physical laws of the familiar kind, there are other laws of nature that are 'biased toward the marvelous'" (p. 92). Such teleological laws, by their status as being teleological, would not be universally applicable and thus temporally historically applicable, functioning only at a particular time and space. With this explanation, Nagel puts forward what he thinks is the best natural explanation for rationality.
The last concept to deal with is value, which stretches the naturalistic scheme to near the breaking-point. Value, which deals with moral and evaluative truth, is what pushes us towards making moral or evaluative judgments. Nagel first denies all subjectivist metaethical theories for moral objectivism. Agreeing with fellow philosopher Sharon Street's position that moral realism is incompatible with a Darwinian account of "the evolutionary influence on our faculties of moral and evaluative judgment" (p. 105), Nagel bites the other end of the bullet and rejects the Darwinian account as inadequate to explain the evolution of value. He notes that the "ability to detect such truth, unlike the ability to detect mind-independent truth about the physical world, would make no contribution to reproductive fitness" (p. 107). He then puts forward the example of pain and pleasure, arguing that there is no reason why pain is bad and pleasure good, since "as far as natural selection is concerned, pain could perfectly well be in itself good, and pleasure in itself bad..." (p. 109). To put it simpler, evolution can only explain judgments of fact, but not of value (The Is-Ought divide). Just because person X intends to murder person Y only tells us what would happen if we decide on certain courses of actions, but not which one is better than the other. For example, one could decide to aid in the murder. Evolution can only explain the judgment that doing so would result in the death of that person, but where is the judgment that says that action is good or bad in itself?
Nagel's proposed solution to the problem of virtue is to embrace some form of teleology, in which "the natural world would have a propensity to give rise to beings of the same kind that have a good — beings for which things can be good or bad" (p. 121). In this manner, the concept of an objective good or evil can be established, much like that of cognition as being inherent to the development of nature.
From the relatively easiest to the hardest to explain, Nagel's metaphysical theory is one of non-reductive emergentism, a panpsychism with a teleological focus. What it is consistent with is some form of spiritual, non-materialistic evolution. He is brilliant yet at the same time remarkably frank about his own presuppositions, admitting that his rejection of theism is purely a priori. Such honesty is commendable, while Christians could certainly benefit from his critique of materialism.