More from Thomas Nagel on Neo-Darwinian Evolution and the Chemical Origin of Life Casey Luskin October 10, 2012 10:43 AM | Permalink Thomas Nagels new Oxford University Press book Mind & Cosmos: Why the Materialist Neo-Darwinian Conception of Nature is Almost Certainly False includes so many compelling statements about the scientific weaknesses in neo-Darwinian evolution and chemical evolution that it would surely violate copyright to reproduce them all for you. But we can share a couple. John West already cited one striking passage where the well-known atheist, philosopher, and legal scholar credits proponents of intelligent design for providing potent criticisms of neo-Darwinian evolution. Nagel concludes that ID proponents do not deserve the scorn with which they are commonly met. It is manifestly unfair. (p. 10) To see exactly where Nagel stands, its worth looking a little deeper into his criticisms of neo-Darwinian and chemical evolution: It is prima facie highly implausible that life as we know it is the result of a sequence of physical accidents together with the mechanism of natural selection. We are expected to abandon this naïve response, not in favor of an alternative that is really a schema for explanation, supported by example. What is lacking, to my knowledge, is a credible argument that the story has a nonnegligible probability of being true. (Thomas Nagel, Mind & Cosmos: Why the Materialist Neo-Darwinian Conception of Nature is Almost Certainly False, p. 6 (Oxford University Press, 2012).) Nagel then poses two questions. He first asks whether the origin of life is likely to have occurred by purely physical and chemical processes alone. The second question pertains to biological evolution, and he frames it in a way that is very similar to how proponents of intelligent design address the same problem. Nagel asks: In the available geological time since the first life forms appeared on earth, what is the likelihood that, as a result of physical accident, a sequence of viable genetic mutations should have occurred that was sufficient to permit natural selection to produce the organisms that actually exist? (p. 6) Nagel begins to answers those two questions as follows: There is much more uncertainty in the scientific community about the first question than about the second. Many people think it will be difficult to come up with a reductionist explanation of the origin of life, but most people have no doubt that accidental genetic variation is enough to support the actual history of evolution by natural selection, once reproducing organisms have come into existence. Nagel, however, observes that the despite the widespread confidence in Darwinian accounts of the evolution of life, the case has not been made: It is no longer legitimate simply to imagine a sequence of gradually evolving phenotypes, as if their appearance through mutations in the DNA were unproblematic -- as Richard Dawkins does for the evolution of the eye. (p. 9) Also, with regard to the origin of life, he observes that the coming into existence of the genetic code -- an arbitrary mapping of nucleotide sequences into amino acids, together with mechanisms that can read the code and carry out its instructions -- seems particularly resistant to being revealed as probable given physical law alone. (p. 10) What is refreshing about Nagels perspective is that hes willing to ask hard questions -- even if those questions go against the consensus, and even if, as he believes, no satisfactory answers are currently on offer. He writes: My skepticism is not based on religious belief or on a belief in any definite alternative. It is just a belief that the available scientific evidence, in spite of the consensus of scientific opinion, does not in this matter rationally require us to subordinate the incredulity of common sense. (p. 7) He continues, observing that too many people simply defer to the consensus and arent willing to take problems with it seriously: [D]oubts about the reductionist account of life go against the dominant scientific consensus, but that consensus faces problems of probability that I believe are not taken seriously enough, both with respect to the evolution of life forms through accidental mutation and natural selection and with respect to the formation from dead matter of physical systems capable of such evolution. (p. 9) Nagel is a bold scholar who is brave enough to think for himself, and isnt going to be bullied into capitulating to the consensus. He has a lot more to say in his book -- and its worth reading. Pick up a copy and see for yourself. Categories: #Evolution, #LifeSciences & #OriginofLife, #Views
Posted on: Sun, 01 Jun 2014 20:33:00 +0000