This is the same comment I left over at Cosmic Variance:

No offense to anyone here but Wheeler himself made the following comment in an interview which I cannot locate but will explain since it is one of the most inciteful things I ever picked up from him. He was asked by his interviewer what he was trying to pass on to his students for them to learn.

His response was that his students never learned a thing from him. Students do not learn from teachers. They learn by teaching.

I took that to mean that when we all turn to stand in front of a class and give a lecture there are many minds in our audience of students. The students’ viewpoints vary over a large spectrum with misinterpretations or new incites that we likely have not considered when we were students. Now, as teachers, we must consider them and be prepared to give a quantitative response if one is possible or an experiment that can realize the answer.