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

I don't try to imagine a personal god; it suffices to stand in awe at the structure of the world, insofar as it allows our inadequate senses to appreciate it.

I do not argue with obstinate men. I act in spite of them.

To forbid us anything is to make us have a mind for it.

Science is not only compatible with spirituality; it is a profound source of spirituality.

Usually when people are sad, they don't do anything. They just cry over their condition. But when they get angry, they bring about a change.

All of us have moments in our lives that test our courage. Taking children into a house with a white carpet is one of them.

Being unwanted, unloved, uncared for, forgotten by everybody, I think that is a much greater hunger, a much greater poverty than the person who has nothing to eat.

If everything isn't black and white, I say, 'Why the hell not?'

I just want to retire before I go senile because if I don't retire before I go senile, then I'll do more damage than good at that point.

When the student is ready, the teacher will appear.

Entrepreneurs are simply those who understand that there is little difference between obstacle and opportunity and are able to turn both to their advantage.

Face the facts of being what you are, for that is what changes what you are.

A scientific man ought to have no wishes, no affections, - a mere heart of stone.

How vain it is to sit down to write when you have not stood up to live.

When you get to a certain age, there is no coming back.

Where grief is fresh, any attempt to divert it only irritates.

You cant have a plan for your day, til you have a plan for your life.

Give up trying to make me give up

Maybe you are searching among the branches, for what only appears in the roots.

I speak for the trees, for the trees have no tongues.