The West needs to relearn what the rest of the world has never forgotten - that there is nothing sinful in leisure as long as it does not degenerate into mere sloth.

A hundred years ago, the electric telegraph made possible-indeed, inevitable-the United States of America. The communications satellite will make equally inevitable a United Nations of Earth; let us hope that the transition period will not be equally bloody.

I sometimes think that the universe is a machine designed for the perpetual astonishment of astronomers.

Religion is the most malevolent of all mind viruses.

There's a passage about 'rivers of molten rock that wound their way... until they cooled and lay like twisted dragon-shapes vomited from the tormented earth.' That's a perfect description: how did Tolkien know, a quarter century before anyone ever saw a picture of Io? Talk about Nature imitating Art.

The difference between machines and human beings is that human beings can be reproduced by unskilled labour.

I'm sometimes asked how I would like to be remembered. I've had a diverse career as a writer, underwater explorer, space promoter and science populariser. Of all these, I want to be remembered most as a writer - one who entertained readers, and, hopefully, stretched their imagination as well.