“Whenever a theory appears to you as the only possible one, take this as a sign that you have neither understood the theory nor the problem which it was intended to solve.”

“Those who are not shocked when they first come across quantum theory cannot possibly have understood it.”

“Men follow their sentiments and their self-interest, but it pleases them to imagine that they follow reason. And so they look for, and always find, some theory which, a posteriori, makes their actions appear to be logical. If that theory could be demolished scientifically, the only result would be that another theory would be substituted for the first one, and for the same purpose.”

“And it is, after all, as good a way as any of solving the problem of existence to get near enough to the things and people that have appeared to us beautiful and mysterious from a distance to be able to satisfy ourselves that they have neither mystery nor beauty.”

“An excellent plumber is infinitely more admirable than an incompetent philosopher. The society which scorns excellence in plumbing because plumbing is a humble activity, and tolerates shoddiness in philosophy because it is an exalted activity, will have neither good plumbing nor good philosophy. Neither its pipes nor its theories will hold water.”

“Now the truth of the matter is that there are a lot of things people don’t understand. Take the Einstein theory. Take taxes. Take love. Do you understand them? Neither do I. But they exist. They happen.”