Politically correct errors are tolerated; offensive truths are shunned.
Freakonomics.com has a very good interview with psychologist Jonathan Haidt. Haidt has written several great books and articles analyzing how humans form moral, ethical and political ideologies. His work has shown that we use our intuitions first followed by strategic reasoning. This should not be too surprising since overall we are emotional creatures. I would say that we are still in our reasoning infancy. Haidt’s work also supports the material reductionist’s stance on human nature as being guided by internal and external stimuli and not the result of some esoteric concept of mind that drives our actions.
Read the interview here.