What strange being could have produced the most caustic, lucid, perplexing satires in the English language? Jonathan Swift has always both attracted and nettled biographers. Soon after his death in 1745, memoirists were jostling to unpuzzle the private life of this censor of his times. Modern biographers have followed their lead, trying to diagnose his misanthropy. All Swift's satires were written in some invented first person – the clever economist with A Modest Proposal to make the Irish eat their babies, the up‑to-date hack who narrates A Tale of a Tub, gullible Gulliver, tumbling from pride to self-disgust; all were published anonymously. Swift is not "there" in any of them. All the more reason for trying to find the author, whom none of us can quite detach from Gulliver in his final dark enlightenment, realising that he is but a Yahoo: sly, vicious and lecherous.