I refuse to engage in an intellectual battle with an unarmed man.

The wonder of nature does not become smaller because one cannot measure it by the standards of human moral and human aims.

I do not believe in the God of theology who rewards good and punishes evil.

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

The world is not threatened by evil people, but by those who allow evil to take place.

When I'm judging a theory, I ask myself whether, if I were God, I would have arranged the world in such a way.

If the bees disappear, man would have only four years of life left.