Moral Minds

I'm enjoying the new Marc Hauser book now. It's like a meta-take on the "Justice" class I took with "Professor" Michael Sandel sophomore year. For example, Sandel seemed to take the following question very seriously as a deep philosophical thought experiment (I paraphrase it):

Maxmillian is standing on a platform above the train tracks, watching an oncoming train. Maxmillian used to design trains and then drive them, so he knows an out-of-control train when he sees one, and right now, he's seeing one. Ludwig, whom Maxmillian has never seen before (he'd recognize him for reasons that will immediately become apparent), due to a glandular problem, weighs so much that his heft alone would be enough to stop the train (without derailing it) before it crashed into the 5 deaf girl scouts who are walking down the tracks, oblivious to the doom rocketing towards them. Is it morally acceptable for Maxmillian to push Ludwig off of the ill-placed platform in order to save the disabled children?

Hauser looks not at the question (his disdain for moral philosophy is at best thinly veiled), but rather at what factors seem to control how people across ages, places, and times would answer the question.