I know that I am intelligent, because I know that I know nothing.

I knew I belonged to the public and to the world, not because I was talented or even beautiful, but because I had never belonged to anything or anyone else.

Man is the only creature that refuses to be what he is.

One man's ways may be as good as another's, but we all like our own best.

The math is dead simple: it seems that the frequency of planets able to support life is roughly one percent. In other words, a billion or more such worlds exist in our galaxy alone. That's a lot of acreage, and it takes industrial-strength credulity to believe it's all bleakly barren.