There is a pivotal scene in The Hobbit where Bilbo Baggins is lost and alone deep under the Misty Mountains, and by happenstance finds the infamous One Ring and puts it in his pocket. Soon after, he encounters the creature Gollum, and is forced to play a riddle game to determine whether Gollum will show him the way out, or eat him instead. Bilbo wins the contest, but Gollum realizes that Bilbo has his ring, which confers invisibility upon the wearer. As Gollum moves to attack him, Bilbo puts on the ring, evades Gollum, and escapes.

But there’s an important caveat here: Bilbo wins by breaking the rules of a game that in Middle-Earth is considered to be “sacred and of immense antiquity.” Bilbo was at a loss to come up with another riddle, and as he fidgeted and fumbled in his pocket he said aloud to himself, “What have I got in my pocket?” Gollum assumed this was a riddle, but of course there was no way he was going to be able to answer it correctly. Yet Bilbo’s question wasn’t a “genuine riddle according to the ancient laws,” as the narrator tells us.

“Sacred and of immense antiquity.” Sounds a lot like human morality, doesn’t it? In a recent essay collection, Thinking, John Brockman observes that “everyone seems to be studying morality these days.” But why are so many devoting so much time to it? Perhaps because moral norms pervade every aspect of our lives, from the most mundane to the most profound. The peculiar thing about morality, however, is that we expect the truly moral person to submit to its demands regardless of her own interests or desires. She should do what morality commands because it is her duty to do so. We want to know why that is.