Arthur C. Clarke

. . . Moon-Watcher felt the first faint twinges of a new and potent emotion. It was a vague and diffuse sense of envy--of dissatisfaction with his life. He had no idea of its cause, still less of its cure; but discontent had come into his soul, and he had taken one small step toward humanity.

Two possibilities exist: Either we are alone in the Universe or we are not. Both are equally terrifying.

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

1. When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong. 2. The only way of discovering the limits of the possible is to venture a little way past them into the impossible. 3. Any sufficiently advanced technology is indistinguishable from magic.

One of the great tragedies of mankind is that morality has been hijacked by religion. So now people assume that religion and morality have a necessary connection. But the basis of morality is really very simple and doesn't require religion at all.

One theory which can no longer be taken very seriously is that UFOs are interstellar spaceships.

Many, and some of the most pressing, of our terrestrial problems can be solved only by going into space. Long before it was a vanishing commodity, the wilderness as the preservation of the world was proclaimed by Thoreau. In the new wilderness of the Solar System may lie the future preservation of mankind.

That's one of those meaningless and unanswerable questions the mind keeps returning to endlessly, like the tongue exploring a broken tooth.

It was one thing to have guessed it, another to have had that guess confirmed beyond possibility of refutation.

Once you can reproduce a phenomenon, you are well on the way to understanding it.

It will be possible in a few more years to build radio controlled rockets which can be steered into such orbits beyond the limits of the atmosphere and left to broadcast scientific information back to the Earth. A little later, manned rockets will be able to make similar flights with sufficient excess power to break the orbit and return to Earth. (1945) [Predicting communications satellites.]

Our lifetime may be the last that will be lived out in a technological society.

One of the biggest roles of science fiction is to prepare people to accept the future without pain and to encourage a flexibility of the mind. Politicians should read science fiction, not westerns and detective stories.

Anything that is theoretically possible will be achieved in practice, no matter what the technical difficulties are, if it is desired greatly enough.

The Earth would only have to move a few million kilometers sunward-or starward-for the delicate balance of climate to be destroyed. The Antarctic icecap would melt and flood all low-lying land; or the oceans would freeze and the whole world would be locked in eternal winter. Just a nudge in either direction would be enough.

Now I'm a scientific expert; that means I know nothing about absolutely everything.

In this single galaxy of ours there are eighty-seven thousand million suns. [...] In challenging it, you would be like ants attempting to label and classify all the grains of sand in all the deserts of the world. [...] It is a bitter thought, but you must face it. The planets you may one day possess. But the stars are not for man.

Few artists thrive in solitude and nothing is more stimulating than the conflict of minds with similar interests.

It was a pity that there was no radar to guide one across the trackless seas of life. Every man had to find his own way, steered by some secret compass of the soul. And sometimes, late or early, the compass lost its power and spun aimlessly on its bearings. Alan Bishop

Now I understand,” said the last man.

Science can destroy religion by ignoring it as well as by disproving its tenets. No one ever demonstrated, so far as I am aware, the nonexistence of Zeus or Thor, but they have few followers now.