When Steele brings up his work with people, the question he gets asked most often is: “What about overpopulation?” He has a go-to answer he thinks highlights the ridiculousness of the question. “Imagine we’re staring down the barrel of 15bn people on Earth,” he says. “There are lots of ways to try and tackle that problem. Would one of them be: invent ageing?”

That he is asked this question so frequently frustrates him. More so, he is bothered by the implication that what he is suggesting is somehow weird or inhuman or unholy, rather than ultimately helpful for society. “If I’d just written a book about how we’re going to cure childhood leukaemia using some amazing new medicine,” he says, “literally nobody would be like, ‘But isn’t that going to increase the global population?’”

He shakes his head.

“What I’m saying is, ‘Here is an idea that could cure cancer, heart disease, stroke…’ Curing any one of those things would get you plaudits. But as soon as you suggest a potentially effective way of dealing with them altogether, suddenly you’re some mad scientist who wants to overpopulate us into some terrible environmental apocalypse?”