“The scientist has a lot of experience with ignorance and doubt and uncertainty, and this experience is of very great importance, I think. When a scientist doesn’t know the answer to a problem, he is ignorant. When he has a hunch as to what the result is, he is uncertain. And when he is pretty damn sure of what the result is going to be, he is still in some doubt. We have found it of paramount importance that in order to progress we must recognize our ignorance and leave room for doubt. Scientific knowledge is a body of statements of varying degrees of certainty-some most unsure, some nearly sure, but none absolutely certain.”
— "What Do You Care What Other People Think?”: Further Adventures of a Curious Character by Richard P. Feynman, p.186
“You see, one thing is, I can live with doubt and uncertainty and not knowing. 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 certainty about different things, but I’m 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, and what the question might mean. I might think about it a little bit and if I can’t figure it out, then I go on to something else, but I don’t have to know an answer,I don’t feel frightened by not knowing things, by being lost in a mysterious universe without having any purpose, which is the way it really isso far as I can tell. It doesn’t frighten me.”
— Richard Feynman - The Pleasure of finding things out.
When you are thinking about something that you don’t understand you have a terrible, uncomfortable feeling called ‘confusion’. It’s a very difficult and unhappy business. And so, most of the time you are rather unhappy, actually, with this confusion. You can’t penetrate this thing. Now, is the confusion… is it because we are all some kind of apes that are kind of stupid working against this? Trying to figure out to put the two sticks together to reach the banana and we can’t quite make it? …the idea? And I get that feeling all the time: that I am an ape trying to put two sticks together. So I always feel stupid. Once in a while, though, everything… the sticks go together on me and I reach the banana.
“No, you’re not going to be able to understand it… You see, my physics students don’t understand it either. That is because I don’t understand it. Nobody does. … The theory of electrodynamics describes Nature as absurd from the point of view of common sense. And it agrees fully with experiment. So I hope you can accept Nature as She is: absurd.”