IN “PERMUTATION CITY”, a novel by Greg Egan, the character Peer, having achieved immortality within a virtual reality over which he has total control, finds himself terribly bored. So he engineers himself to have new passions. One moment he is pushing the boundaries of higher mathematics; the next he is writing operas. “He’d even been interested in the Elysians [the afterlife], once. No longer. He preferred to think about table legs.” Peer’s fickleness relates to a deeper point. When technology has solved humanity’s deepest problems, what is left to do?

That is one question considered in a new publication by Nick Bostrom, a philosopher at the University of Oxford, whose last book argued that humanity faced a one-in-six chance of being wiped out in the next 100 years, perhaps owing to the development of dangerous forms of artificial intelligence (AI). In Mr Bostrom’s latest book, “Deep Utopia”, he considers a rather different outcome. What happens if AI goes extraordinarily well? Under one scenario Mr Bostrom contemplates, the technology progresses to the point at which it can do all economically valuable work at near-zero cost. Under a yet more radical scenario, even tasks that you might think would be reserved for humans, such as parenting, can be done better by AI. This may sound more dystopian than utopian, but Mr Bostrom argues otherwise.