It is a truism that the structure of a society is basically determined by its technology. Not in an absolute sense-there may be totally different cultures using identical tools-but the tools settle the possibilities; you can't have interstellar trade without spaceships. A race limited to a single planet, possessing a high knowledge of mechanics but with its basic machines of industry and war requiring a large capital investment, will inevitably tend toward collectivism under one name or another. Free enterprise needs elbow room.

So much American science fiction is parochial - not as true now as it was years ago, but the assumption is one culture in the future, more or less like ours, and with the same ideals, the same notions of how to do things, just bigger and flashier technology. Well, you know darn well it doesn't work that way.

Better a life like a falling star, brief bright across the dark, than the long, long waiting of the immortals, loveless and cheerlessly wise.

He had seen too much of the cosmos to have any great faith in man's ability to understand it.

I think the first duty of all art, including fiction of any kind, is to entertain. That is to say, to hold interest. No matter how worthy the message of something, if it's dull, you're just not communicating.

Colonization means potential immortality for the human genus. Man's safety on Earth was never great, and it dwindles hourly. Disarmament, even world government, will not guarantee survival in an age when population presses natural resources to the limit and when the knowledge of how to work mischief on a planetary scale is ever more widely diffused among peoples who may grow ever more desperate.

In Harvest of Stars, there is this notion, not original with me of course, that it will become possible to download at least the basic aspects of a human personality into a machine program.