The Man Who Knew Too Much: Alan Turing and the Invention of the Computer was published by W.W. Norton in 2006, as part of the Great Discoveries series. The biography tells the story of Alan Turing (1912-1954) — the British mathematician whose 1936 paper “On Computable Numbers” laid the theoretical foundations for modern computing, whose wartime codebreaking at Bletchley Park was instrumental in defeating Nazi Germany, and whose criminal prosecution for “gross indecency” (homosexuality) in 1952 led to chemical castration and, in 1954, his death from cyanide poisoning (ruled suicide, though theories of accident persist).
Leavitt brings a novelist’s sensibility to the biography: he is particularly good on the emotional texture of Turing’s life — the loneliness of genius, the pain of concealment, the brief happiness of his relationship with Arnold Murray, and the horror of the prosecution and its aftermath. As a gay writer, Leavitt understands from inside the particular cruelty of a society that simultaneously benefits from a man’s gifts and punishes him for his nature.
The mathematical content is presented accessibly without being condescending: Leavitt explains the significance of the Turing machine, the Entscheidungsproblem, and the Enigma decryption in terms that a general reader can follow while preserving the intellectual excitement of the ideas.
The biography appeared before Turing’s rehabilitation became a major public cause (the official pardon came in 2013, the apology in 2009), and it contributed to the growing recognition that Turing’s treatment was not merely unjust but catastrophic — the destruction of one of the twentieth century’s greatest minds by the state he had helped save.
Collecting The Man Who Knew Too Much
First edition (W.W. Norton, New York, 2006): Hardcover, dust jacket.
Market values:
- First edition, fine/fine: $15–$30
- Very good/very good: $5–$15