The playing field was level in a way that it isn't when you're teaching youngsters. I stood to learn as much from them as they did from me: these were people with wide and serious experience. For instance, I taught the philosophy of economics to our class this past summer. When you're talking with people who have worked their whole lives, often in minimum-wage jobs or marginal employment, the conversation takes on more depth. The problems and their responses are more urgent and more deeply felt.