The Last Word on Teleology, or Optimality Models Vindicated

Abstract

In their work biologists frequently use language apparently making reference to ends or consequences or goals, as, for instance, when they say that “the purpose or function of the heart is to pump the blood”, or that “the heart exists in order to pump the blood”. This ‘teleological’ dimension to biology attracts a great deal of attention from philosophers, although those of us with nasty minds suspect that the essence of the attraction does not really lie in the topic itself — certainly the attraction does not lie in solving a problem in biology for its own sake. Rather, what draws philosophers towards teleology is that one has to know, or at least it is generally thought that one has to know, absolutely no biology at all! One makes a dutiful obeisance in the direction of the life sciences by noting that the heart beats in order to pump the blood and that it does not beat in order to produce heart sounds, and then one can cheerfully move the discussion into the unreal world of the imagination so beloved by philosophers. Biology forgotten, one can talk about door knobs serving as paper weights, sewing machines with buttons to be pressed when one wants them to self-destruct, multi-purposed water beds, or whatever else it is that turns one on; in the unreal world of the imagination, that is! And if someone like myself tries to bring matters back to biology, smugly pointing out that perhaps heart sounds do serve an end, namely soothing babies at the maternal breast, the objection is considered irrelevant — almost bad form in fact. Philosophers want no empirical factors deflecting them in their neo-scholastic pursuits (Figure 4.1).