This is an obvious cross-reference for this group—indeed, many of you likely already read it. Peter Singer and Agata Sagan have an column in NYTimes' "The Stone" today called "Are We Ready for a Morality Pill?" They present the conundrum of the how to factor in our growing understanding of the effect of brain chemistry not just on our mood and temperment, but also our inclination toward morally good actions. Essentially, there's growing evidence that there are significant brain-chemical correlations not only for rather clear psychological pathologies like schizophrenia, major depression, and extreme anti-social behaviors, but also more subtle distinctions like our sensitivity for morally good behavior and our predisposition for altruistic or good-samartian-type acts. (We talk about some of this in our neurobiology episode with Pat Churchland.) Singer and Sagan conclude with:
But if our brain’s chemistry does affect our moral behavior, the question of whether that balance is set in a natural way or by medical intervention will make no difference in how freely we act. If there are already biochemical differences between us that can be used to predict how ethically we will act, then either such differences are compatible with free will, or they are evidence that at least as far as some of our ethical actions are concerned, none of us have ever had free will anyway. In any case, whether or not we have free will, we may soon face new choices about the ways in which we are willing to influence behavior for the better.
So, part of what we face here is that the variety in our behaviors and dispositions has some significant portion that is like the variation in our heights or the amount of our body hair. Such variations are just part of the myriad of distinctions between one human and another. Put that way, we're faced with the question of what culpability for our actions really means—we certainly don't expect to hold people guilty for their extreme height or their hair loss (though, pertinently, both have social effects).
I'm inclined to put a slightly different spin on it, however. Our chemistry, like the rest of our bodies, mark limitations, but generally a range rather than a determined value or relation—a boundary that constrains without determination. Sometimes, that boundary is very tight. For instance, as a group we humans can tolerate fairly little variation in the amount of potassium in our blood without dying. In other cases the boundary is pretty loose. We flourish is nearly all the climates on the earth. The question we have socially is how much variation in behavior do we tolerate (even encourage) and what do we do about it before generating technological solutions to the failures of our physiology. (Shelter and clothing anyone?) Faced with the possibility of modifying even more behaviors through advancing knowledge of how chemistry affects moral behavior, we must confront the need to make explicit judgements about letting unapproved, even bad things, happen, just as much as we concern ourselves with encouraging good things to happen and hamper bad ones.