What is genius like? Newton left over 8 million words of notes at his death, and somewhere in that mass was the answer. But many of those who first got a glimpse of them were so appalled at what they found that, as Sarah Dry, the author of this fascinating tale recounts, they made sure the bulk of the papers ‘remained unexamined, hidden from sight for more than seven generations’.

It was only the keen eye of John Maynard Keynes and others, at a Sotheby’s auction in 1936, that helped bring the papers to a wider audience. Soon after Keynes began skimming them, he realised – as he put it in a public lecture – that ‘Newton was not the