Insanity: doing the same thing over and over again and expecting different results.

The world is a dangerous place to live; not because of the people who are evil, but because of the people who don't do anything about it.

Learn from yesterday, live for today, hope for tomorrow. The important thing is not to stop questioning.

A person who never made a mistake never tried anything new.

Any man who can drive safely while kissing a pretty girl is simply not giving the kiss the attention it deserves.

When you are courting a nice girl an hour seems like a second. When you sit on a red-hot cinder a second seems like an hour. That's relativity.

The difference between stupidity and genius is that genius has its limits.

Gravitation is not responsible for people falling in love.

We cannot solve our problems with the same thinking we used when we created them.

Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.

The true sign of intelligence is not knowledge but imagination.

A question that sometimes drives me hazy: am I or are the others crazy?

Try not to become a man of success, but rather try to become a man of value.

Anyone who doesn't take truth seriously in small matters cannot be trusted in large ones either.

Great spirits have always encountered violent opposition from mediocre minds.

Only a life lived for others is a life worthwhile.

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

A man should look for what is, and not for what he thinks should be.

It's not that I'm so smart, it's just that I stay with problems longer.

Education is what remains after one has forgotten what one has learned in school.

Anyone who has never made a mistake has never tried anything new.

Before God we are all equally wise - and equally foolish.

No problem can be solved from the same level of consciousness that created it.

You have to learn the rules of the game. And then you have to play better than anyone else.

There are two ways to live: you can live as if nothing is a miracle; you can live as if everything is a miracle.

Logic will get you from A to B. Imagination will take you everywhere.

All religions, arts and sciences are branches of the same tree.

If people are good only because they fear punishment, and hope for reward, then we are a sorry lot indeed.

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

Peace cannot be kept by force; it can only be achieved by understanding.

Science without religion is lame, religion without science is blind.