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

Better know nothing than half-know many things.

To educate a person in the mind but not in morals is to educate a menace to society.

Books are for people who wish they were somewhere else.

My weapon is literature

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

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

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

It is not enough for the teacher to love the child. She must first love and understand the universe. She must prepare herself, and truly work at it.

The deepest sin against the human mind is to believe things without evidence.

You can never learn less, you can only learn more.

The ability to observe without evaluating is the highest form of intelligence.

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

It is possible to fly without motors, but not without knowledge and skill.

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

Make it a rule never to give a child a book you would not read yourself.

For a successful technology, reality must take precedence over public relations, for Nature cannot be fooled.

Necessity is the mother of invention.

If you want the present to be different from the past, study the past.

Real knowledge is to know the extent of one's ignorance.

Know what you are talking about.