For all my desire to be interesting, I have to confess that for most things and people I don't give a damn.

Success is to be measured not by wealth, power, or fame, but by the ratio between what a man is and what he might be.

The religion of the atheist has a God-shaped blank at it's heart.

I write as straight as I can, just as I walk as straight as I can, because that is the best way to get there.

I felt the first inkling of a thing that presently grew quite clear in my mind, that oppressed me for many days, a sense of dethronement, a persuasion that I was no longer a master, but an animal among the animals, under the Martian heel.With us it would be as with them, to lurk and watch, to run and hide; the fear and empire of man had passed away.

Crude classifications and false generalizations are the curse of the organized life.

When the history of civilization is written, it will be a biological history and Margaret Sanger will be its heroine.