I’m just reading a review copy of Steven Pinker’s (excellent) new book The Better Angels of Our Nature: Why Violence Has Declined.
This section, on how moral motivation is over-rated as a control on violence, just made me laugh out loud.
The human moral sense can excuse any atrocity in the minds of those who commit them, and it furnishes them with motives for acts of violence that bring them no tangible benefit. The torture of heretics and conversos, the burning of witches, the imprisonment of homosexuals, and the honor killing of unchaste sisters and daughters are just a few examples. The incalculable suffering that has been visited on the world by people motivated by a moral cause is enough to make one sympathize with the comedian George Carlin when he said “I think motivation is overrated. You show me some lazy prick who’s lying around all day watching game shows and stroking his penis and I’ll show you someone who’s not causing any fucking trouble!”
Link to more information on the book.
Mind Hacks 
Honor Code by Appiah is about how moral revolutions (abolition of dueling, foot-binding, and dueling, for example) have happened. I’ve only heard an interview about the book, but I believe the idea is that people can know the moral and practical arguments against a bad practice, but nothing changes until they come to believe that the bad practice is the sort of thing an inferior person would do.
Haha! Looking forward to reading the book.
In concert with this, I’d recommend Baumeister’s “Evil: Inside Human Violence and Cruelty.” The two tie together very well.