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

Just because I don't care doesn't mean I don't understand.

Patience is a virtue, and I'm learning patience. It's a tough lesson.

No power and no treasure can outweigh the extension of our knowledge.

If I have seen further it is by standing on the shoulders of Giants.

If you can't explain it simply, you don't understand it well enough.

A cynic is a man who knows the price of everything, and the value of nothing.

Seek knowledge from the cradle to the grave.

Integrity without knowledge is weak and useless, and knowledge without integrity is dangerous and dreadful.

I decided to teach because I think that any person who studies philosophy has to be involved actively.

Language is courage: the ability to conceive a thought, to speak it, and by doing so to make it true.

Education is the ability to listen to almost anything without losing your temper or your self-confidence.

It isn't what we don't know that gives us trouble, it's what we know that ain't so.

Knowledge is of two kinds. We know a subject ourselves, or we know where we can find information upon it.

Never help a child with a task at which he feels he can succeed.

Know what you are talking about.

Medicine is my lawful wife and literature my mistress; when I get tired of one, I spend the night with the other.

A child miseducated is a child lost.

We could never learn to be brave and patient, if there were only joy in the world

Suddenly degrees aren't worth anything. Isn't that true? When I was a student, if you had a degree, you had a job. If you didn't have a job it's because you didn't want one. And I didn't want one, frankly.

You can never be overdressed or overeducated.