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

The books that the world calls immoral are books that show the world its own shame.

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

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

It is beyond a doubt that all our knowledge begins with experience.

An investment in knowledge pays the best interest.

The knowledge of all things is possible

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

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

What we know is a drop, what we don't know is an ocean.

All stable processes we shall predict. All unstable processes we shall control.

I think that kids have a greater capacity for processing things than we give them credit for.

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

Science is not only a disciple of reason but, also, one of romance and passion.

Books are as useful to a stupid person as a mirror is useful to a blind person.

The first principle is that you must not fool yourself and you are the easiest person to fool.

The more I read, the more I acquire, the more certain I am that I know nothing.

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.

I am a part of everything that I have read.

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

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