Tuesday, October 01, 2019

Thomas Nagel on Materialism

Thomas Nagel is an atheist and professor of philosophy at New York University. I have just read his book called Mind and Cosmos: Why the Materialist Neo Darwinian Conception of Nature is Almost Certainly False. The book is a hard read, but he has some interesting comments about the weakness of the evidence for evolution.

For a long time, I have found the materialist account of how we and our fellow organisms came to exist hard to believe, including the standard version of how the evolutionary process works. The more details we learn about the chemical basis of life and the intricacy of the genetic code, the more unbelievable the standard historical account becomes (p.5).

What is lacking, to my knowledge, is a credible argument that the story has a nonnegligible probability of being true. There are two questions. First given what is known about the chemical basis of biology and genetics, what is the likelihood that self-producing life forms should have come into existence spontaneously on the early earth, solely through the operations of the laws of physics and chemistry? The second question is about the sources of variation in the evolution process that was set in motion once life began. 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 selection to produce the organisations that actually exist (p.6)?

The available evidence is very indirect, and general assumptions have to play an important part (p.7).

Doubts 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 system capable of such evolution. The more we learn about the intricacy of the genetic code and its control of the chemical processes of life, the harder these problems seem.

Again; with regard to evolution, the process of natural selection cannot account for the actual history without and adequate supply of viable mutations, and I believe it remains an open question whether this could have been provided in biological time merely as a result of chemical accident without the operation of some other factors determining and restricting the forms of genetic variation.

With regard to the origin of life, the problem is much harder, since the option of natural selection as an explanation is not available. And the coming into existence of the genetic code—and 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 provable given physical laws alone (p.10).

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