It is science fiction that holds a mirror to this age

From a talk by Brian W Aldiss, the science-fiction novelist, delivered at the Royal Society of Literature in London

What interesting times we live in! Those of us who have survived the Second World War and the Cold War have witnessed the discovery of nuclear power, the exploration by probe of the planets of the solar system, and now the mapping of the human genome. It has been an intellectual feast, if an indigestible one at times.

What interesting times we live in! Those of us who have survived the Second World War and the Cold War have witnessed the discovery of nuclear power, the exploration by probe of the planets of the solar system, and now the mapping of the human genome. It has been an intellectual feast, if an indigestible one at times.

Science fiction is a child of these times. It comes, as they say, with the territory. Science fiction endeavours to tell this thrilling serial story, often in metaphorical terms. Once it was said that SF (to use its pet name) was a predictive genre. That may still be partially true, although those of us who trade in the unlikely are bound to be right some of the time, so unlikely is the modern world.

I prefer to see SF as a mirror to the present. Set up that mirror 50 years into the future and today's confusions become clearer. Of course, this tends to imbue SF with a moralising tone. In the past, SF stories sometimes took the place of 18th-century sermons; particularly in the Sixties, when we were professionally gloomy about nuclear war and overpopulation. Nowadays, much SF, as it addresses a wider audience, becomes more the equivalent of technological fairy stories. But generalising is dangerous. SF is far from homogeneous; there are as many approaches as there are authors.

One thing any writer should do is question - question the society in which he lives, and the rules under which that society lives. For instance, we may believe that the West flourishes, as indeed it does, by taking economic advantage of the rest of the world. Doubt is a costly luxury; but a lifetime of reading and writing SF has persuaded me that doubt is a necessity and conviction an enemy. Always believe in change, even if it comes in the shape of a spaceship.

Fantasies about getting to other planets and about weird creatures living on them are of considerable antiquity. But modern SF begins, appropriately, after the Napoleonic wars have speeded industrialisation, in the heart of the Romantic movement, when young Mary Shelley wrote her astonishing novel Frankenstein, or the Modern Prometheus (published 1818). In that novel, for the first time, mankind by scientific means usurps the power of God in creating life. Her novel marks an end to superstition, an end to mindlessly following the dicta of previous generations. It speaks, as she says, "to the mysterious fears of our nature''.

Mary Shelley confirmed her futuristic bent by going on to write a novel with the ominous title The Last Man, a disaster story in which the human race is destroyed. We see in The Last Man, disguised, the events and loves of Mary Shelley's own life, just as Mary is her own rejected monster in Frankenstein. Literary critics tend to forget that not everything in a book comes from other books: by setting their stories in future time, as HG Wells did later, authors can distance themselves from the events of their personal lives.

What is the essential difference between a SF story and the contemporary or domestic variety? SF is far less inclined to look back on the recent past with nostalgia - as does, say, John Betjeman's poetic Summoned by Bells, with his cloying love of his teddy and the suburbs, and the minute social differences between his family and the neighbouring one. SF aims higher than that - even if, in aiming higher, it shoots itself in the foot. It prefers to talk about the consequences of Now, stretching its long shadows forward, not back.

I had intended not to utter a paean of praise for SF, but the thought of Betjeman's cosy-wosy world, and of all those snug, safe modern English novels featuring parsons and Agas and pet dogs and respectability - and no sense at all that we live through a crisis, intellectual, economic and climatic - rouses me up to give a hearty cheer for the outsider literature of science fiction.