Before another century is done it will be hard for people to imagine a time when humanity was confined to one world, and it will seem to them incredible that there was ever anybody who doubted the value of space and wanted to turn his or her back on the Universe.

To those who are trained in science, creationism seems a bad dream, a sudden coming back to life of a nightmare, a renewed march of an Army of the Night risen to challenge free thought and enlightenment.

The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!' but 'That's funny...'

What would I do if I knew I only had six months to live? Type faster.

It is in meeting the great tests that mankind can most successfully rise to great heights. Out of danger and restless insecurity comes the force that pushes mankind to newer and loftier conquests.

People are entirely too disbelieving of coincidence.

The Master created humans first as the lowest type, most easily formed. Gradually, he replaced them by robots, the next higher step, and finally he created me, to take the place of the last humans.