HOW, if at all, will the 1990s be remembered? The Internet rose and the Soviet Union fell. Mammals were cloned, Bosnia broke up, and peace came to Ireland, maybe. Something happened in Canada, though no one was sure precisely what. On the whole it has been a decade like any other, agreeably dull. In a thousand years, or in ten thousand or a hundred thousand, what will matter? Mainly an event which hardly anyone noticed at the time: the first, tentative sprouting of an idea which can transfigure humanity.

Thank—if you think it cause for thanks—Les U. Knight of Portland, Oregon. Great ideas sometimes have peculiar beginnings, and Mr Knight is a case in point. He knows that the idea for which he acts as principal spokesman is featured in a book called “Kooks: A Guide to the Outer Limits of Human Belief”, and on a related website called “Kooks Museum”. This does not trouble him, since he is lucky to be listed in any sort of reference work at all. “I don't mind being considered a kook; somebody's got to do it,” he says in his gentle, almost musical baritone. “This is the natural progression of ideas. First we have to be ridiculed.” In that, if in nothing else, the Voluntary Human Extinction Movement looks set for creditable success.

Mr Knight is a middle-aged substitute teacher in Portland's secondary schools, but it is for his avocation that history should remember him. Around 1970, when he was back from service in the Vietnam war and was finishing university, he became interested in the environmental movement, which was just celebrating its first Earth Day. This sparked a number of changes in his personal philosophy (and also the insertion of the “U.” into his name). “It took a very short time to see that all of the environmental solutions were linked to the number of people on the planet,” he says. He joined a group called Zero Population Growth, but soon saw that this was no permanent solution. “That's when I realised that the best thing for the planet would be for us to phase ourselves out completely.”

In his imagination, if nowhere else, Mr Knight became the founder of the Human Extinction Movement; but over time he realised that the name he had chosen missed the central element which sets his vision apart as both liberal and sublime. “It's got to be voluntary,” he says—a Voluntary Human Extinction Movement (VHEMT, pronounced, he intones, “vehement”, because that is what they are). There is more than enough coercion in the world already, he reckons, and in any case governments that cannot manage forests should not be expected to manage people.

Since 1991 he has used newsletters to ask people to become Movement “volunteers” by forswearing procreation. The task, he concedes, is difficult, but the longest journey begins with a single step. “I consider it a success every time one more of us decides not to add one more of us.” The movement has no organisation or membership list, and consists of anyone who supports the idea. How many followers it boasts is impossible to say. In 1995 Daniel Metz, a Willamette University researcher, counted close to 400 people on Mr Knight's mailing list, and even managed to survey them. The supporters tend to believe two things: that humans will soon face a massive “die-off” as population surges past the planet's carrying capacity, and that humans would do the world a favour by going away, because their continuation obliterates so many other species.

“In a short time,” says a middle-aged New Yorker, in an e-mail to your correspondent, “we'll see the unmistakable signs of the next big population crash.” Meanwhile, so long as humans continue, we wreak destruction. “We can't help it,” avers a vehement woman from Jersey City, “and we can't stop ourselves—we simply must strip the earth of all natural resources, and drive other species to extinction, for our own short-term benefit.”

It must be said, with all respect, that neither rationale is quite compelling. The notion of a growing number of people fighting over a fixed resource pie is Malthusian bosh, as this newspaper has argued in the past. Human ingenuity, energised by sensible policies, creates resources faster than people use them; people learn to substitute sand (in the form of microchips) for sweat, and fuel cells for petrol engines. The second contention—that humanity owes it to other species to die off—is a little harder to dismiss. The egalitarian premise that Homo sapiens has no innate moral precedence over other species, which human activity does indeed obliterate at an impressive rate, is one you must simply take or leave. If you take it, then at a minimum humans should find ways to leave a smaller footprint. Still, that argues for better conservation, or perhaps for fewer humans. It is not a compelling argument for no humans at all.

At about this point in the article, the clever reader begins to wonder why a serious newspaper is wasting ink on such silly ideas. The answer is that once in a while someone comes up with the right idea for the wrong reasons. Mr Knight's notion of voluntary human extinction is one of those profoundly right ideas.

Consider, in this connection, a question so obvious, and so important, that it has rarely if ever been posed: Why should there always be a next generation? Of course parents will make one, at least for the foreseeable future, but to say they have no choice in the affair is a reply suitable for a bacillus or a slime mould or a tumour, not for a thinking being. The command to make children and grandchildren, to be fruitful and multiply for ever and ever, is an imperative of the genes, not the mind. Humans will be the slaves of two little coils of nucleotide bases so long as they fail to take into their own hands the ultimate question, which is how long the People Show should go on.

An exit chosen, not ordained

It is clear that human history will end; the only mystery is when. It is also clear that if the timing is left to nature (or, if you prefer, to God) and humans hang on until the bloody end, the race's final exit will be ignoble. If future generations escape the saurian agony of extermination by a wandering chunk of rock or ice, the sun's unavoidable growth to gianthood will still incinerate their last successors: only cinders and gases and dust will remain.

Far future generations might prolong the process by posting colonies beyond the earth's orbit, but these would be sad outposts at the end of the solar system's long day, clutching memories of a lost planet and of billions of immolated souls. The difficulties—fantastic difficulties—of interstellar travel might be overcome, but the mightiest of starships could do no more than defer the dies irae. An ignoble existence hopping from planet to planet—clinging to each clod until it, in its turn, was vaporised or frozen—might still be bearable were it not for the knowledge of its final futility. In the end, there is only death by gravity or entropy, the fiery quantum pit or the heatless grey soup.

The great violinist Jascha Heifetz was great not least because he quit the concert stage at his peak, before the show became stale or the audience drifted away. To exit gracefully is sublime, as Heifetz understood. And only one species is capable of choosing a similarly graceful exit; all others march on like robots. To call time on the human race by choice, not necessity, would be the final victory of the human spirit over animal nature, an absolute emancipation from the diktat of DNA. Precisely because no other known life-form could do or even conceive such a thing, humanity must.

More: science has revealed only one place in the universe that is hospitable to intelligent life, and humans are the only intelligence that, as far as is known, has ever enjoyed the opportunity to occupy it. If people left the stage after a reasonable run, in the fullness of time intelligence could evolve again (dolphin-people? chimp-people? orchid people?). And then, in due course, when this new species deciphered human books or reached the marker that might be left for them on the windless moon, they would know that man ended his dominion so that theirs might begin. Imagine, then, how they will regard us. It is, far and away, the greatest act of goodness ever contemplated, the ennoblement of a whole species; an act, almost, of angels.

By departing the scene humanity will leave much undiscovered, much unexplored and unfinished. Perhaps in the reaches of space there is life, or even intelligence: a pity to extinguish the race before meeting it. Yet the future is always an unwritten page, and the nobility of voluntary extinction resides precisely in shutting the book at a time of our own choosing. To make contact with an alien race while still alive would be interesting, for a while; but mankind will doubtless make a better impression posthumously. Then the aliens will know the ancients of earth as a legendary race that gave itself back to the dust and the stars. They will speak of us with awe to their children for as long as, ignoring our example, they continue to have any.

Imagine the poetry, the music, of those last few human generations; imagine the moral exaltation of those last few souls, the pregnant richness of sound and light and colour and even of thought in the last months of humanity's twilight. Who would not give everything to know the ineffable sadness and nobility of being among the last? Then, at last, the lights will go out, and the world will begin anew, and the sand will cover our name. That would be a finale worthy of a great race.

It is hard, indeed, to imagine any reason to be against voluntary human extinction. The tricky question is not whether to extinguish, but when. Certainly not right away, if only because, as yet, we can't. As Mr Knight himself says, “Convincing 6 billion people to stop breeding is indeed a daunting task.” But there need be no rush. Look at it this way. For humans to reach a state of such collective rational consensus that they become capable of choosing their end may take a few millennia, or a few dozen or a few hundred millennia; but this decision need only be made once. When even the last few men and women left holding out answer the call to the sublime, and choose to bear no more children—then that will be the species' finest hour. And so that will be the time to leave. The timetable of voluntarism is perfect: it provides ample time, but not a day too much of it.

Let this article be a hopeful obituary, then, for a race that may yet hurl its defiance into the teeth of the cosmos, and surpass itself as no earthly creature has ever done before. Let Homo sapiens' epitaph say that nothing in our career became us like the ending of it.