“Of course, I am interested, but I would not dare to talk about them. In talking about the impact of ideas in one field on ideas in another field, one is always apt to make a fool of oneself. In these days of specialization there are too few people who have such a deep understanding of two departments of our knowledge that they do not make fools of themselves in one or the other.”

“Pompous fools drive me up the wall. Ordinary fools are alright; you can talk to them and try to help them out. But pompous fools – guys who are fools and covering it all over and impressing people as to how wonderful they are with all this hocus pocus – THAT, I CANNOT STAND! An ordinary fool isn’t a faker; an honest fool is all right. But a dishonest fool is terrible!”

“There was a Princess Somebody of Denmark sitting at a table with a number of people around her, and I saw an empty chair at their table and sat down.She turned to me and said, "Oh! You're one of the Nobel-Prize-winners. In what field did you do your work?""In physics," I said."Oh. Well, nobody knows anything about that, so I guess we can't talk about it.""On the contrary," I answered. "It's because somebody knows something about it that we can't talk about physics. It's the things that nobody knows anything about that we can discuss. We can talk about the weather; we can talk about social problems; we can talk about psychology; we can talk about international finance--gold transfers we can't talk about, because those are understood--so it's the subject that nobody knows anything about that we can all talk about!"I don't know how they do it. There's a way of forming ice on the surface of the face, and she did it!”

“I can live with doubt and uncertainty and not knowing. I think it is much more interesting to live not knowing than to have answers that might be wrong. If we will only allow that, as we progress, we remain unsure, we will leave opportunities for alternatives. We will not become enthusiastic for the fact, the knowledge, the absolute truth of the day, but remain always uncertain … In order to make progress, one must leave the door to the unknown ajar.”

“How can we tell whether the rules which we "guess" at are really right if we cannot analyze the game very well? There are, roughly speaking, three ways.First, there may be situations where nature has arranged, or we arrange nature, to be simple and to have so few parts that we can predict exactly what will happen, and thus we can check how our rules work. (In one corner of the board there may be only a few chess pieces at work, and that we can figure out exactly.)A second good way to check rules is in terms of less specific rules derived from them. For example, the rule on the move of a bishop on a chessboard is that it moves only on the diagonal. One can deduce, no matter how many moves may be made, that a certain bishop will always be on a red square. So, without being able to follow the details, we can always check our idea about the bishop's motion by finding out whether it is always on a red square. Of course it will be, for a long time, until all of a sudden we find that it is on a black square (what happened of course, is that in the meantime it was captured, another pawn crossed for queening, and it turned into a bishop on a black square). That is the way it is in physics. For a long time we will have a rule that works excellently in an over-all way, even when we cannot follow the details, and then some time we may discover a new rule. From the point of view of basic physics, the most interesting phenomena are of course in the new places, the places where the rules do not work—not the places where they do work! That is the way in which we discover new rules.The third way to tell whether our ideas are right is relatively crude but prob-ably the most powerful of them all. That is, by rough approximation. While we may not be able to tell why Alekhine moves this particular piece, perhaps we can roughly understand that he is gathering his pieces around the king to protect it, more or less, since that is the sensible thing to do in the circumstances. In the same way, we can often understand nature, more or less, without being able to see what every little piece is doing, in terms of our understanding of the game.”

“It was thought in the Middle Ages that people simply make many observations, and the observations themselves suggest the laws. But it does not work that way. It takes much more imagination than that.So the next thing we have to talk about is where the new ideas come from. Actually, it does not make any difference, as long as they come.”

“They didn't put two and two together. They didn't even know what they knew. I don't know what's the matter with people, they don't learn by understanding; they learn by some other way—by rote, or something. Their knowledge is so fragile!”