In January 1962, Sir Oswald Mosley, founder of the British Union of Fascists, wrote to Bertrand Russell fishing for a public debate on fascism’s merits. Russell, then a few months from turning ninety, declined without a shred of debate-club politeness: “The emotional universes we inhabit are so distinct, and in deepest ways opposed, that nothing fruitful or sincere could ever emerge from association between us.” He signed it “Yours sincerely.”