Just when I thought there wasn't room enough for another thought in my head, I had this great idea.

The only true wisdom is in knowing you know nothing.

Action not backed by knowledge and knowledge not translatable into action, both can not stand the test of time.

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

If the facts don't fit the theory, change the facts.

I cannot teach anybody anything. I can only make them think

When I am attacked by gloomy thoughts, nothing helps me so much as running to my books. They quickly absorb me and banish the clouds from my mind.

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

To every action there is always an equal and opposite or contrary, reaction

Learn as though you would never be able to master it; hold it as though you would be in fear of losing it.

A thought is an idea in transit.

Don't worry that children never listen to you; worry that they are always watching you.

There is nothing more awful, insulting, and depressing than banality.

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.

Many much-learned men have no intelligence.

The reading of all good books is like conversation with the finest men of past centuries.

It is what you read when you don't have to that determines what you will be when you can't help it.

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

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

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

Show me a family of readers, and I will show you the people who move the world.