The universe must be full of voices, calling from star to star in a myriad tongues. One day we shall join that cosmic conversation.

A faith that cannot survive collision with the truth is not worth many regrets.

We always thought the living Earth was a thing of beauty. It isn’t. Life has had to learn to defend itself against the planet’s random geological savagery.

Getting information from the internet is like getting a glass of water from the Niagara Falls.

I'm surprised at some technological development, and the realization that any sufficiently advanced technology is indistinguishable from magic. I think the CD-ROM is the best example of that. The idea of having a whole symphony, or opera, or novel in a little piece of plastic is pretty amazing.

I believe any malevolent supercivilisation would have rapidly self-destructed as we may be in the process of doing ourselves. If we do have contact, physical contact with aliens, I think it will be benign.

The choice, as Wells once said, is the Universe-or nothing. . . . The challenge of the great spaces between the worlds is a stupendous one; but if we fail to meet it, the story of our race will be drawing to its close. Humanity will have turned its back upon the still untrodden heights and will be descending again the long slope that stretches, across a thousand million years of time, down to the shores of the primeval sea.