Richard P. Feynman

"I thought one should have the attitude of 'What do you care what other people think!"

"I think that when we know that we actually do live in uncertainty, then we ought to admit it; it is of great value to realize that we do not know the answers to different questions. This attitude of mind - this attitude of uncertainty - is vital to the scientist, and it is this attitude of mind which the student must first acquire."

"We are trying to prove ourselves wrong as quickly as possible, because only in that way can we find progress."

"Religion is a culture of faith; science is a culture of doubt."

"I learned very early the difference between knowing the name of something and knowing something."

"The first principle is that you must not fool yourself and you are the easiest person to fool."

"Physics is like sex: sure, it may give some practical results, but that's not why we do it."

"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."

"I think it's much more interesting to live not knowing than to have answers which might be wrong. I have approximate answers and possible beliefs and different degrees of uncertainty about different things, but I am not absolutely sure of anything and there are many things I don't know anything about, such as whether it means anything to ask why we're here. I don't have to know an answer. I don't feel frightened not knowing things, by being lost in a mysterious universe without any purpose, which is the way it really is as far as I can tell."

"I have a friend who's an artist and has sometimes taken a view which I don't agree with very well. He'll hold up a flower and say look how beautiful it is, and I'll agree. Then he says I as an artist can see how beautiful this is but you as a scientist take this all apart and it becomes a dull thing, and I think that he's kind of nutty. First of all, the beauty that he sees is available to other people and to me too, I believe. Although I may not be quite as refined aesthetically as he is ... I can appreciate the beauty of a flower. At the same time, I see much more about the flower than he sees. I could imagine the cells in there, the complicated actions inside, which also have a beauty. I mean it's not just beauty at this dimension, at one centimeter; there's also beauty at smaller dimensions, the inner structure, also the processes. The fact that the colors in the flower evolved in order to attract insects to pollinate it is interesting; it means that insects can see the color. It adds a question: does this aesthetic sense also exist in the lower forms? Why is it aesthetic? All kinds of interesting questions which the science knowledge only adds to the excitement, the mystery and the awe of a flower. It only adds. I don't understand how it subtracts."