Francis Bacon composed his autobiography in paint, not words. His portraiture laid bare the skull beneath the skin, the beast pregnantly housed inside the human form, and all of the figures he painted – copulating men, hybrid monsters, bystanders at a crucifixion, many of them trapped in chrome cages or sadomasochistic cellars – were fractured images of himself. The verbal self-portrait that Michael Peppiatt has assembled could never match that lacerating self-scrutiny; in his correspondence, his scrappy memos for paintings and his repetitive interviews, Bacon hid behind evasive banality or wilful obscurity. Descended from Irish gentry, he took a snobbish...