It’s an old line: When asked about the experience of teaching, a teacher replies that he learned more from the students than they learned from him. One can understand the impulse, and why the answer endures as a kind of proverb or cliché: it’s an expression of humility; it resists the impression of the master dispensing Knowledge from on high; it conjures a classroom in which student and teacher collaborate together in the search for knowledge; it appeals to our democratic sensibilities; it might even tickle our know-nothing instincts, dormant though they may be.