Eternal life, in heaven or through reincarnation on Earth, is promised by many faiths. For a simple reason: it eases the fear of death.
The idea of living forever has other devotees, too. It is now pursued by a motley crew of fringe scientists, cultish groups and tech billionaires, united by a conviction that a way to make humans immortal will eventually be found.
Meanwhile, they pin their hopes on experimental, often fraudulent therapies that promise rejuvenation.
In “The Price of Immortality”, Peter Ward, a journalist who has written for The Economist, delves into the origins of these beliefs and the science of purported cures for ageing.
He spends time with groups such as the Church of Perpetual Life in Florida, where congregants discuss food supplements and cryonics (the freezing of bodies at death in the hope that they can be revived later).
America’s “immortalists”, he discovers, are inspired by the dreams of futurists such as the science-fiction writer Isaac Asimov.
Another influence is Nikolai Fedorov, a 19th-century Russian philosopher who thought all living beings could, one day, be resurrected using traces of them floating around in the cosmos—a vision that brings to mind modern DNA cloning.
“Longevity escape velocity” is one of the immortalists’ central tenets. This notion holds that if science manages to extend the human lifespan by 20 or 30 years—to around 110 or 120—it will then rise exponentially as new techniques are developed in time to keep the wizened going longer and longer.
The hypothesis was floated in 2004 by Aubrey de Grey, a British scientist prominent in the field of age-reversal, whose work caught the attention of Silicon Valley moguls.
This is not all pure fantasy. Gene and stem-cell therapies and other types of regenerative medicine can tackle some of the ways in which ageing causes natural deterioration—though these methods are yet to be turned into proven and safe treatments.
That may not take long, though. Tech magnates such as Sergey Brin and Larry Page, the co-founders of Google, and Jeff Bezos of Amazon have been pouring money into longevity research.
Some of the startups conducting it have billions of dollars at their disposal and are poaching leading scientists.
As an investor tells Mr Ward, the goal is extending healthy life spans, not freezing decrepit bodies that might “wake up in 200 years from now and commit suicide if they can”.
Some immortalists back an even more radical aim: doing away with the body and resurrecting a dead person’s mind in a robot or through an alternative digital reality.
The theory is that this could be accomplished using scans of brain tissue or by applying artificial intelligence to reconstruct a personality from “mind files”—vast amounts of digital data accrued during the subject’s life. Tech titans are bankrolling this moonshot, too.
Digital immortalists, like adherents of cryonics, accept that the chances of success are slim; but they are willing to put in the work and money anyway.
Mr Ward combines thorough reporting and lucid scientific explanations in a fluent and balanced account of a diverse movement. He is a vivid storyteller, from the tragicomedies of cryonics’ early years to tales of scam artists and reckless zealots.
And he ponders a world in which people do indeed live a lot longer. Even if old age is made healthier, drastic new kinds of inequality—and political strife—could result. If scientists succeed in making death optional, concludes Mr Ward, resolving such issues will be a prerequisite for a “world worthy of a longer stay”.