In mathematics you don't understand things. You just get used to them.
The most savage controversies are those about matters as to which there is no good evidence either way.
It isn't what we don't know that gives us trouble, it's what we know that ain't so.
A cynic is a man who knows the price of everything, and the value of nothing.
Science is what we have learned about how to keep from fooling ourselves.
Books are for people who wish they were somewhere else.
Education is the most powerful weapon which you can use to change the world.
Education is the kindling of a flame, not the filling of a vessel.
Opinion is the medium between knowledge and ignorance.
Real knowledge is to know the extent of one's ignorance.
There is nothing more notable in Socrates than that he found time, when he was an old man, to learn music and dancing, and thought it time well spent.
If you want the present to be different from the past, study the past.
What we know is a drop, what we don't know is an ocean.
As we acquire more knowledge, things do not become more comprehensible but more mysterious.
If the facts don't fit the theory, change the facts.
There is one quality which one must possess to win, and that is definiteness of purpose, the knowledge of what one wants, and a burning desire to possess it.
If one cannot enjoy reading a book over and over again, there is no use in reading it at all.
It is what you read when you don't have to that determines what you will be when you can't help it.
I cannot live without books.
The whole of science is nothing more than a refinement of everyday thinking.
The only true wisdom is in knowing you know nothing.