Reading is to the mind what exercise is to the body.

My alma mater was books, a good library.... I could spend the rest of my life reading, just satisfying my curiosity.

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

All knowledge that the world has ever received comes from the mind; the infinite library of the universe is in our own mind.

Necessity is the mother of invention.

Imagination is the source of every form of human achievement. And it's the one thing that I believe we are systematically jeopardizing in the way we educate our children and ourselves.

I like poems you can tack all over with a hammer and there are no hollow places.

What is freedom of expression? Without the freedom to offend, it ceases to exist.

A witty saying proves nothing.

An investment in knowledge pays the best interest.

I have no special talents. I am only passionately curious.

Opinion is the medium between knowledge and ignorance.

Better know nothing than half-know many things.

The real solution lies in a world in which charity will have become unnecessary.

It is better to know how to learn than to know.

A man who has never gone to school may steal a freight car; but if he has a university education, he may steal the whole railroad.

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

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

A little knowledge that acts is worth infinitely more than much knowledge that is idle.

You can never be overdressed or overeducated.

In order to stave off covetouness, greed, and spite, citizens world over must be educated.