We stand now at the turning point between two eras. Behind us is a past to which we can never return... The coming of the rocket brought to an end a million years of isolation... the childhood of our race was over and history as we know it began.

The time was fast approaching when Earth, like all mothers, must say farewell to her children.

Isn't killing people in the name of God a pretty good definition of insanity?

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.

But please remember: this is only a work of fiction. The truth, as always, will be far stranger.

Trying to predict the future is a discouraging and hazardous occupation. If by some miracle a prophet could describe the future exactly as it was going to take place, his predictions would sound so absurd that people everyone would laugh him to scorn. The only thing we can be sure of about the future is that it will be absolutely fantastic. So, if what I say now seems to you to be very reasonable, then I will have failed completely. Only if what I tell you appears absolutely unbelievable have we any chance of visualizing the future as it really will happen.

The realisation that our small planet is only one of many worlds gives mankind the perspective it needs to realise sooner that our own world belongs to all its creatures.