If we have learned one thing from the history of invention and discovery, it is that, in the long run-and often in the short one-the most daring prophecies seem laughably conservative.

When one has to ask, "Am I really in love?" the answer is always "No".

To find anything comparable with our forthcoming ventures into space, we must go back far beyond Columbus, far beyond Odysseus-far, indeed, beyond the first ape-man. We must contemplate the moment, now irrevocably lost in the mists of time, when the ancestor off all of us came crawling out of the sea.

If there are any gods whose chief concern is man, they can't be very important gods.

I sometimes wonder how we spent leisure time before satellite television and Internet came along…and then I realise that I have spent more than half of my life in the ‘dark ages’!

You can't have it both ways. You can't have both free will and a benevolent higher power who protects you from yourself.

Before the current decade ends, fee-paying passengers will be experiencing suborbital flights aboard privately funded vehicles. . . . It won't be too long before bright young men and women set their eyes on careers in Earth orbit and say: "I want to work 200 kilometers from home-straight up!"