
Finn Brunton
THE STORY of the 2015 hack of the adulterous-hookup dating site Ashley Madison starts with a party in Manchester, UK, in 1950. It’s a hypothetical fete, imagined by the great mathematician, computing pioneer, and cryptanalyst Alan Turing, at which a game is played: You, the “interrogator,” are sitting at a teletype keyboard or something like it, chatting with a man (X) and a woman (Y). They’re both trying to convince you that they’re female; the object of the game is for you to guess correctly who really is. You ask: “Will X please tell me the length of his or her hair?” The man tries to pass