Though it was only briefly mentioned in class, I'm interested in the 'Wisdom of Repugnance', less so for its moral validity, more so for its implications.
The idea is criticized for being an appeal to emotion, and thus intrinsically fallacious, which is undeniably true. Disgust is not a good barometer for morality as shown by movements such as slavery, anti-semitism, prohibition, etc..
Yet somewhat contrarily, one has to concede that disgust is relevant not only as an evolutionary mechanic to avoid disease (fear of bugs, sores, rotting food, etc.) but also in some social norms (incest, murder... table etiquette?). These fears or anxieties usually don't merit a logical explanation because they are generally accepted as valid.
It is when the emotion is "co-opted" morally into non-relevant phenomena such as xenophobia that it loses its validity. Consider the cavemen days where xenophobia would be contributory to survival (other tribes were generally hostile), however, and disgust suddenly seems normative, or at the very least justifiable in a primitive context.
Perhaps we simply live in a time where social change occurs faster than we can adapt our evolutionary intuitions. But then can any deep-seated intuition really be considered normative? We operate plenty on the "pleasure over pain" idea, as well as the assumption that that warm, tingly feeling indicates moral behavior. What do you guys think?