by Patrick Appel

Ron Replogle uses the abortion debate to explain political group formation:

Your ideological community is the class of people whose moral and political sensibility, their inventory of political principles and battery of moral reflexes, carry weight in your political deliberation. An ideologue is prepared to reject a favorite principle when enough of her ideological comrades have sufficiently powerful moral qualms about its applications. And she’ll swallow her own moral qualms about a principle when she and her comrades can’t think of a better one.

This needn’t be a matter of peer pressure subverting one’s better judgment.

All other things being equal, a conviction’s being shared by a deliberative community large and culturally diverse enough not to be taken in by idiosyncratic or narrowly parochial prejudices, but sufficiently like-minded to unite behind a substantive political agenda, is a good reason for believing it. That makes the gravitational pull ideological communities exert on the content of their members’ beliefs an essential feature of political rationality. When such a community deliberates effectively, its members draw on the wisdom of the group to attain a measure of objectivity they can’t achieve on their own. When it deliberates less-than-rationally, its members’ views will be ill-considered.

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