Sunday, October 14, 2012

South Dakota Politics: Teleology & Efficient Causation in Biology

If you want to know what a college is supposed to be, spend some time on the third floor of the Tech Center at NSU. On Friday Professor Schaff and I sat in my office discussing the difference between the concepts of the cosmos and of the universe and the limits on legitimate teleological explanations in biology. A third colleague of ours joined in the discussion and, in effect, so did a fourth: the cosmos/universe distinction was put forth by someone who was not present.

As I understand the first question, both terms stand for the whole of things in space and time (excluding alternative universes or a God who stands outside space and time). To call this whole a cosmos is to imply that it is ordered and coherent in the same way as a beating human heart is ordered and coherent. To call the whole a universe is to avoid any such suggestion. The universe may be a disordered mess without any hierarchy or coherence of any kind. I apologize to my absent colleague if I got this wrong.

I am not entirely comfortable with the terminology. The term universe can also imply coherent order just as the term university does. However, I accept the distinction and I think it is important, though I will not tip my hand on this one. The suggestion was made that a cosmos has to involve teleology, which is to say that its order must be understood in terms of the ends or goals which that order serves. At that point I stated that teleology is indeed involved in biological explanations.

There the discussion shifted to a more specific question: taking Darwinian theory seriously, what counts as a telos or goal in organic activities? It was put forth that survival is a Darwinian telos. I argued to the contrary and what follows is my argument after a little thinking.

Aristotle distinguished four basic kinds of explanations, of which only two concern us here. Consider the flight of an arrow from the bow to the target. An efficient explanation goes like this: the energy imparted by the bow string to the arrow was sufficient to carry the arrow in the right direction and far enough to reach the bulls eye. A teleological explanation focuses on the intentions of the archer: he hit the target because that is what he was aiming at. The two kinds of explanations are not in any way at odds with one another; they are simply answers to different questions.

Although this position is not uncontroversial in the philosophy of biology, I think that teleological explanations are entirely appropriate and indeed essential in biology. The growth of an animal from its original cell is an end-directed process. Countless subordinate processes are constantly being redirected toward the telos: a mature adult. Likewise, when a bull elk pursues a cow in heat, his actions are guided by a pre-programed goal. The philosopher of biology Ernst Mayr called such program-guided processes teleomatic.

Now for the question: is survival among the teloi, if not the telos, of biological processes? I say no. First, survival is purely subordinate to successful reproduction in Darwinian biology. Secondly, the bull is neither trying to survive nor trying to produce offspring. What he is trying to do is mate. That is the telos of his amorous actions. Okay, but isn't reproduction the reason for his actions? Yes, but this is an efficient rather than a teleological explanation.

An efficient explanation begins with some action or event and works backward in time to articulate the causes that produced it. The arrow flew because first the string pushed it. The string pushed it because first the archer pulled it back and then let it go. It doesn't matter where you start in time, with the arrow, the string, or the biceps, efficient explanation works backwards in time.

A teleological explanation proceeds forward in time from the action to the goal that the action was intended to achieve. The archer releases the string at time T1 because he intended the arrow to reach the target at T2.

The bull's amorous pursuit is explained teleologically by the goal that he is trying to achieve in the near future: mating. If we could read the elk's DNA coherently, we would find a set of genetic information adding to a schema that guides mating behavior, predator avoidance, etc. What we wouldn't find is language coding for survival of the individual or the species.

How do survival and successful reproduction figure in as explanations? The bull behaves as he does because his father behaved that way. Every existing organism is the offspring of an unbroken line of successful breeders. Natural selection is efficient causation, not teleological causation.

This distinction is rather important. Critics of Darwinism frequently argue that it is brutish because it reduces all values to the mere struggle to survive and reproduce. This is flat wrong. Fitness for survival and reproduction are not values in any sense in the theory. They are efficient forces that explain how the forms of the various organisms emerge and are sustained.

I think that I and my colleagues came to some agreement on this, but as a result of that conversation I have clarified my own thoughts. If you want to know what a college really is, that would be it.

Source: http://southdakotapolitics.blogs.com/south_dakota_politics/2012/10/teleology-efficient-causation-in-biology.html

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