But I *do* think the shorter-term examples, such as the sea change in the nation’s attitude toward slavery or civil rights (or capitalism in the 80′s), does show that people’s minds can be changed. It takes oceans of patience and hard work. But it can be done. We’re seeing that now as the nations rapidly shifts its attitudes on gays. It’s happening far too quickly to represent a swap of prejudices.

But the broader point is correct. Once people shift their attitudes, they then become very stubborn in their holding onto the new ones.

You attribute people’s beliefs changing with time to the influence of reason. How do you know that they aren’t simply exchanging one set of prejudices for another or accumulating new prejudices? If your hypothesis is correct, then we should see a trend with age toward more reason-based political beliefs. The oldest among us should therefore be among the best articulators of the reasons behind their political thinking. Is this the case in your experience?