Tuesday, October 26, 2010

Irreducible Complexity

In the debate between intelligent design advocates and their Darwinian opponents, the claim is made by the IDers that there are systems in living things that are irreducible complex, i.e. they could not have evolved step by gradual step because they cannot function until all the parts are in place and operating. The bacterial flagellum is considered the paradigmatic example of IC but there are numerous others.

This site, for example lists a couple dozen systems or structures that are alleged to be irreducibly complex. Whether they are or not may be debated, but I'll leave that debate to others more qualified than I. Here are some examples for which the article offers brief explanations:
  1. Bacterial Flagellum
  2. Eukaryotic Cilium
  3. Aminoacyl-tRNA Synthetases (aaRS)
  4. Blood clotting cascade
  5. Ribosome
  6. Antibodies and the Adaptive Immune System
Students of biology will find the complete list interesting reading.

Psychological Egoism

Here's a question: Does genuine altruism exist in human beings? By this I mean, do human beings, or better, can human beings, act for the benefit of others if there's no benefit in the act for the doer? Do we do what we do for others only because we believe, if even subconsciously, that there's some benefit in the act for us?

Before you answer you should read a brief essay by Georgetown philosophy professor Judith Lichtenberg on just this question.

Lichtenberg notes that psychological egoism (PE), the view that all our actions, including those ostensibly done for others, are really done for self-benefit, is impossible to falsify. This means that one cannot imagine a circumstance which, if it obtained, would prove PE wrong. The inability to think of such a circumstance means that the theory can't be tested and this is, in fact, a detriment. Immunity to testing is a weakness in a theory, not a strength.

Lichtenberg might have also mentioned that PE is ultimately based upon circular reasoning. To see this consider the case of Wesley Autrey which she discusses in the beginning of her piece. Autrey risked his life in 2007 to rescue a man who had fallen onto the subway tracks in New York City as a train bore down upon him.

To the question, what was in it for Autrey the PE might reply that Autrey hoped for a reward, either monetary, psychological or perhaps even eternal, for doing what he did. Suppose, though, that upon being interviewed Autrey denies that any of those considerations ever entered his mind. He didn't have time to think, he attests. He saw the man fall, he saw the train approach, and he reacted.

The PE might then resort to this fallback position: "There must have been some self-benefit in saving the man that Autrey felt." If asked why there must be such a motive, the PE can only answer, "because saving the man is what he did and everything people do they do in their own self-interest."

In other words,

  1. We always act for our own benefit
  2. Cases where people seem to act genuinely for others only seem to be altruistic. There's always a self-beneficial purpose buried somewhere in the person's motivations.
  3. We know there must be a self-beneficial motive driving the person's act because we always act for our own self-benefit.
This is a circular argument and circular arguments are logically invalid. Thus, although PE seems formidable, it's ultimately based on fallacious reasoning.

Anyway, read Lichtenberg's column and see what you think.