Free Will as a good threory in some situations

Lisa Randall, a physicist at Harvard University, points out that even when a scientific theory is superceded by a new theory (and a new paradigm), it often remains useful and indeed more useful in some domains. Thus Einstein's theory of relativity has supplanted Newton's theory of gravity as the most general and accurate in describing motion, as judged by the profession of professional physicists. However, Newtonian equations are used in lots of applications such as the the analysis of trajectories of projectiles, Newton is as accurate for all practical purposes in these applications and a lot easier to use.

Indeed, while there has been some popular interest in "a theory of everything", science advances by developing theories for application in specific domains. Physicists have good theories that atoms are composed of protons, neutrons and electrons, and that these are themselves composed of smaller units, quarks. No one would think of trying to analyze the behavior of the planets starting from the quarks of which they are ultimately composed. So too, psychologists do not start their analysis from neurobiology, nor do macro economists from consumer psychology nor even micro economic models.

I recently posted including the thought that "free will" might be regarded as a theory that is very useful for some purposes, but not necessarily for others. The idea was very much in the spirit of Dr. Randall's comment, and perhaps triggered by it.

I would suggest that when one is faced by a decision, it is best to regard oneself as having free will. Far too many bad decisions (or decisions to be bad) can be justified or rationalized as the result beyond the control of the decision maker. The most admirable decisions are often those which are unlikely -- someone from a poor neighborhood filled with people choosing crime or ignorance to dedicate herself to learning and service, or someone in a jingoistic community en route to war standing for peace against all probability.

On the other hand, there are situations in which I would say free will is not the right theory. Most people would agree that we should not treat poor behavior by people with limited rationality (small children, the insane, seriously mentally retarded) as culpable as we would the same act by a fully rational adult; in some sense those with limited rationality are not as free to choose the right course as their more rational neighbors. Can we feel that the citizens of North Korea, exposed constantly and only to propaganda, are best considered as having free will. Do we assume that the unwanted and uneducated member of an underclass, abusing substances commonly abused in his community, has the same free will as his contemporary different in all these respects? I think not.

In many cases, the model of people's actions as statistically dependent on a number of partial determinants is more illuminating and useful than one of people acting of their own free will.

More generally, is is not only useful to command many theories as one goes through life analyzing and making decisions, but it is important to know which theory to use in which circumstances.