In 1999, the futurist Ray Kurzweil published a book entitled The Age of Spiritual Machines. He looked forward to a future in which the “human species, along with the computational technology it created, will be able to solve age-old problems?.?.?.?and will be in a position to change the nature of mortality.”

Mr Kurzweil is now an executive at Google, one of whose co-founders, Larry Page, launched a start-up, Calico, in 2013 with the aim of harnessing advanced technologies that will enable people to “lead longer and healthier lives”.

Others go even further. Aubrey de Grey, co-founder of Strategies for Engineered Negligible Senescence, a research centre, believes that ageing is just an engineering problem. Technological progress, he maintains, will eventually enable human beings to achieve what he calls “life extension escape velocity”.