"Don't ever do a calculation without knowing the answer."

"Don't ever do anything that you don't want to explain to a student."

"We are like children who have found a new toy. We do not know what to do with it, but we are playing with it."

"It does not say in the Bible that all laws of nature are expressible linearly!"

"Before I came here I was confused about this subject. Having listened to your lecture I am still confused. But on a higher level."