This frustrating exposition, after all, yields a satisfying conclusion. Nagel frustrates with his opaque writing style, and, nearly as frustrating, he rejects the NeoDarwinian account, when it comes to the origin of consciousness, rationality and value—yet retains it in his teleological alternative. That is, he schizophrenically honors the heart of the Darwinian doctrine, natural selection, while insisting that the doctrine is almost certainly wrong. Go figure.
What Darwin Got Wrong." But Nagel dismisses the centerpiece of their attack—the incoherence of natural selection theory—cavalierly, to my mind, opining in a footnote that they misinterpret the theory. Really? How so? Now, that would be worth reading.
Which is not to say that the present book is not. When someone of Nagel's stature presents secular objections to the NeoDarwinian paradigm, feathers are bound to fly, as they do in any number of critical reviews of the book. Science seems to feel pressured to circle the wagons around the Darwinian account no matter the veracity of the counter arguments. It's time to take a break.
Conventional thinkers who keep natural selection theory at the top of their list of explanatory tools can use it to explain any aspect of organic nature. They need only contend that whatever is observed, say consciousness and rational thought, or blue feathers and big beaks, is as it is because that phenotypic trait was "more adaptive" than the alternatives expressed in the ancestral population. If in some instances that explanation seems implausible, then the explanation is “genetic drift.”
In any case, Nagel sidesteps this catch-all application of Darwinian reductionism by pointing out that nature from the outset must have had the potential to sprout living beings with minds. Nothing in conventional scientific thinking accounts for this potential inhering in nature. The prospect transcends the materialist, NeoDarwinian paradigm, or at least that's Nagel's contention.
Nagel advocates as an alternative a natural monism in which ontological bedrock occurs at the intersection of objectivity and subjectivity. Alfred North Whitehead and Charles Hartshorne receive acknowledging footnotes, but Nagel owes them more than footnotes. Any reader of Mind and Cosmos who comes away asking, "Where's the beef?" ought to find an introductory text on Whitehead's process philosophy. Whitehead is a denser read than Nagel, but worth it. Charles Hartshorne took the theological ball from Whitehead and ran with it to score impressively, as a philosopher of theology working in the academy in the twentieth century. He built a rigorously logical case for God's existence. An unconventional God, but still. Maybe Nagel’s aversion to God keeps him from incorporating more overtly the ideas of Whitehead and Hartshorne, their thinking seeming so obviously to dovetail with his own.
Pondering the prospects for panpsychism, Nagel says that he doesn't see how consciousness of partials might through any additive process produce higher-level consciousness. On this point I fault him for not being familiar with the collaborative work of Roger Penrose and Stuart Hameroff. Their model of consciousness draws on quantum physics, not only to reconcile the simultaneity of objectivity and subjectivity, a la Whitehead, and Hartshorne, but also to account for lesser and greater instances of consciousness. An aspect of the Penrose-Hameroff model is the proposed existence of electrons retained in quantum coherent states in neuronal microtubules and these quantum coherencies spanning many neurons. A quantum indeterminacy, of whatever magnitude, whether involving coherence of a few or of a heap of electrons (or any other kind of particle) occasions a proportionately rich moment of subjective experience when it collapses into an objective event. This model of nature’s inherent capacity for subjectivity gets around Nagel's problem of parts and wholes.
Which brings us to Nagel’s broad target: materialism. Since the quantum revolution, what exactly is this "material" at the foundation of materialism? I'm not saying that we should wave a quantum wand wantonly at problems in philosophy of mind. But neither should we pretend still to inhabit a Newtonian world made up ofDemocritean atoms, little bits of insentient stuff. Materialism is due for a re-definition.
The work of Whitehead, Hartshorne, Penrose and Hameroff deserves more acknowledgement than Nagel offers. Then again it's a small book. Also missing is any reference to complexity theory, with its emphasis on nature's capacity for self-organization. It would seem concomitant to any natural teleology, though bringing enthusiasts for teleology to within arm's length of the discredited doctrine of vitalism. In any case, Nagel straddles the fence, arguing for a natural teleology, or teleonomy, minus the theism or deism that traditionally attaches to such notions.
Natural teleology implies that evolution is going somewhere in particular, but it does not imply a determinism. It implies that evolution's direction is, at least to a degree, of its own accord and not entirely a matter of straining under the stresses of contingency but, nonetheless, that the process needs a suitable milieu in which to unfold.
Given the above, what would reconcile natural teleology with a secular worldview?
Development.
It's a simple conceptual move: Natural history is re-conceived of as a process of development, as being a life history. The history of the universe, including expressions of biology and of consciousness, rational thought, and values, unfolds in stages. It is an organism developing, with all of the expected teleological implications of such a model. A developmental model of nature is an alternative to both a God-directed nature and an undirected one. It is an alternative to the options generally taken for granted during the past hundred years.
The developmental model demonstrates its efficacy when applied to, for example, critique of Nagel's argument that H. Allen Orr wrote for the New York Review of Books (Feb 7, 2013). Orr raises facts about organic nature that ostensibly argue against natural teleology. But he assumes that teleology must operate in a particular manner.
After commenting on the proliferation of types of organisms, and their adventures and their extinctions, he says, "The point is that, if nature has goals, it certainly seems to have many and consciousness would appear to be fairly down the list." So it might seem. But the developmental model accounts for the seeming anomaly. When a human zygote, for example, gives rise to the proliferation of cell types that constitutes a developing body, does that imply that the process has lost its direction and become scattered? Does it imply that the developmental process lacks a particular preferred adult phenotype, that it fails to proceed, teleologically, in a preferred direction? Giraffe, Norway pine, and certified public accountant are equally prospective outcomes of any given ontogeny? No, the adult form is constrained phenotypically by the genotype of the zygote, teleologically in effect--despite the body’s proliferation of cell types. Extinctions during natural history don't count against teleology, either, at least not in a developmental model. Various cell types come and go during the developmental cycle of a complex organism, particularly in those organisms that undergo radical metamorphoses. Discarding something no longer needed is no evidence of abandoning a goal. And so it is with evolution, the terrestrial leg of the stellar life cycle.
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