The celebrated author rejected his cradle Catholicism for scientific materialism but could never quite let go of the spiritual

Crime pays, at least when it comes to fiction. Whodunnit, whydunnit, legal thriller, locked-room, murder mystery: the list goes on. A third of all books sold in the United Kingdom are drenched in blood, stuffed with dead bodies, and overrun by psychopaths. Our literary love affair with criminality is often traced to the 1920s and 1930s, the so-called “golden age” of detective fiction; but it was Arthur Conan Doyle who, in the twilight of the nineteenth century, really established the genre. Sherlock Holmes was by no means the first fictional investigator, but when he came to life as “the great detective”, something shifted.

Curiously, though, the greatness of Sherlock Holmes is not an expression of boundlessness but rather of limitation. G.K. Chesterton admired Conan Doyle’s tales above all for their economy. Take the example of “Silver Blaze”. A valuable race-horse is stolen, and the trainer guarding him murdered by the thief; various people are plausibly suspected of the theft and murder, and everyone concentrates on who could have killed the trainer – until Holmes realises that it was the horse that had killed the trainer. Because it is the precious jewel, Chesterton explains, the horse is not suspected of being also the deadly weapon. Brilliant simplicity.