“We absolutely must leave room for doubt or there is no progress and there is no learning. There is no learning without having to pose a question. And a question requires doubt. People search for certainty. But there is no certainty. People are terrified — how can you live and not know? It is not odd at all. You only think you know, as a matter of fact. And most of your actions are based on incomplete knowledge and you really don’t know what it is all about, or what the purpose of the world is, or know a great deal of other things. It is possible to live and not know.”

“I couldn’t claim that I was smarter than sixty-five other guys–but the average of sixty-five other guys, certainly!”

“When it came time for me to give my talk on the subject, I started off by drawing an outline of the cat and began to name the various muscles.The other students in the class interrupt me: “We *know* all that!””Oh,” I say, “you *do*? Then no *wonder* I can catch up with you so fast after you’ve had four years of biology.” They had wasted all their time memorizing stuff like that, when it could be looked up in fifteen minutes.”

“All the time you’re saying to yourself, ‘I could do that, but I won’t,’ — which is just another way of saying that you can’t.”