This is an essential part of our story. Americans now bear such animosity toward one another that it’s almost as if many are holding up signs saying,… - Jonathan Haidt

Although I am a political liberal, I believe that conservatives have a better understanding of moral development (although not of moral psychology in general — they are too committed to the myth of pure evil). Conservatives want schools to teach lessons that will create a positive and uniquely American identity, including a heavy dose of American history and civics, using English as the only national language. Liberals are justifiably wary of jingoism, nationalism, and the focus on books by “dead white males,” but I think everyone who cares about education should remember that the American motto of e pluribus, unum (from many, one) has two parts. The celebration of pluribus should be balanced by policies that strengthen the unum.

If you take home one souvenir from this part of the tour, may I suggest that it be a suspicion of moral monists. Beware of anyone who insists that there is one true morality for all people, times, and places — particularly if that morality is founded upon a single moral foundation. Human societies are complex; their needs and challenges are variable.

If you think that moral reasoning is something we do to figure out the truth, you’ll be constantly frustrated by how foolish, biased, and illogical people become when they disagree with you. But if you think about moral reasoning as a skill we humans evolved to further our social agendas — to justify our own actions and to defend the teams we belong to — then things will make a lot more sense.