Suppes, Patrick - Reflections on Ernest Nagel's 1977 Dewey Lectures Teleology Revisited

04/12/2013

The Journal of Philosophy, Aug/Sept 2012

This paper is a summary and examination of Nagel's 1961 chapters on biological teleology and Nagel's further arguments in the 1977 Dewey lectures. In the first section, author reviews Nagel's 1961 arguments against teleological explanation being "essential" to biology: (1) the teleological can be given analogues with the mechanical, (2) the teleological used to be the account for most physical processes, which have since been replaced by the mechanical (thus teleology in biology might be only provisional). Nagel's point is that a type of system theory will also do for biological explanation, that that biology doesn't require "a radically distinctive logic of inquiry". (pg506)

In the next section, author skips to Nagel's 1977 discussions of the various shortcomings of newer theories about explanation in biology. One analysis is of Mayr's "program" view, which separates some biological functions into the "teleomatic" and the "teleonomic" (pg507). The teleomatic is "automatic, as is the case for many human habits" and the teleonomic is more in line with the teleological. Author summarizes Nagel's main objections: That just because a process is controlled by a program does not mean it's teleological, and finding a good criterion to distinguish between the supposed two kinds of programs is not possible. The last part of this section includes Nagel's restatement of his theory which is now called the "system-property view", which includes a difficulty with variables that are not "determinantly connected by known laws of nature" (pg508).

Section III examines the second half of chapter 12 in Nagel's The Structure of Science. In it, Nagel responds to the arguments offered by biologists resisting reduction of biology to physics. Nagel concludes that though this is not possible (yet), there must remain this possibility (pg509). The next section author shows Nagel's discussion of functional explanations and focuses on Nagel's criticisms of functional explanations that may smuggle in teleology, such as: "blood contains leucocytes for the sake of defending the body against invading bacteria." (pg510). Nagel deals with Hempel's analysis of the possibility of multiple causes (pg511) and also a view Nagel is sympathetic to in Michael Ruse's "welfare" view. Nagel's views are summarized on the bottom of pg512. The final section of the paper is author's comments on biological explanation with particular extended discussion on how solving the problem of consciousness will lead to ever more intermixing of physics, chemistry, and biology.