This could be frightening, but we already knew something was wrong. Here's the path to understanding why all our attempts to understand the problems attending the human condition have so far failed.

It's pretty to think that we all decide our political affiliations by methodically studying each party's positions on the issues. But a recent study by Paul Goren at Arizona State found that voters typically formed their party affiliations before developing specific political values. They become Democrats first and then decide that they, say, oppose capital punishment and support trade unions. But how do they make that initial decision to be a Democrat? The most likely indicator of political preference is your parents' party affiliation, but if everyone simply voted along family lines, the dominant party would simply be the one whose members had the most voting offspring. The real question is why someone would ever break from the family tradition -- without feeling strongly either way about specific issues.

Those M.R.I. scans suggest an explanation. Perhaps we form political affiliations by semiconsciously detecting commonalities with other people, commonalities that ultimately reflect a shared pattern of brain function. In the mid-1960's, the social psychologist Donn Byrne conducted a series of experiments in which the participants were given a description of several hypothetical strangers' attitudes and beliefs. They were then asked which stranger they would most enjoy having as a co-worker. The subjects consistently preferred the company of strangers with attitudes similar to their own. Opposites repel.

Of course people don't make all their decisions this way. From continental drift to Newtonian physics, some ideas have managed to win assent from pretty much everyone capable of understanding them. It's definitely worthwhile figuring out how to move politics from one category to the other. Per unit effort, it would probably be more help to our grandchildren than college trust funds.