I would defend the liberty of consenting adult creationists to practice whatever intellectual perversions they like in the privacy of their own homes; but it is also necessary to protect the young and innocent.

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.

There were some things that only time could cure. Evil men could be destroyed, but nothing could be done with good men who were deluded.

No one of intelligence resents the inevitable.

One orbit, with a radius of 42,000 kilometers, has a period of exactly 24 hours. A body in such an orbit, if its plane coincided with that of the Earth's equator, would revolve with the Earth and would thus be stationary above the same spot on the planet. It would remain fixed in the sky of a whole hemisphere ... [to] provide coverage to half the globe, and for a world service three would be required, though more could be readily utilized. (1945) [Predidicting geosynchronous communication satellites]

Overhead, without any fuss, the stars were going out.

In accordance with the terms of the Clarke-Asimov treaty, the second-best science writer dedicates this book to the second-best science-fiction writer. [dedication to Isaac Asimov from Arthur C. Clarke in his book Report on Planet Three]