A man who counted
From The Economist print edition
ADVANCED mathematics is a hard sell, but David Leavitt's biography of Alan Turing, which was published in America last December and is just coming out in Britain, will give even the most innumerate reader an idea of the beautiful and fascinating world he is missing.
Mr Leavitt does not use the word, but in today's parlance Turing, a brilliant misfit who laid the foundations of modern computing and cryptography, would probably have been called autistic. He took things very literally, was almost incapable of lying, cared little for his outward appearance, and was rather bad at understanding what other people felt or meant. None of that helped him live a happy life.
But understanding numbers was another story. Turing's mathematical genius first flowered at school, and then bloomed in the laid-back, brainy atmosphere of 1930s Cambridge. His “vice” (as many termed it then) of homosexuality was regarded sympathetically, at least within the walls of King's College.
The author does a fair job of portraying both the world of pre-war scholarship and the Bletchley Park code-breaking centre where Turing spent the war years. There he created electro-mechanical contraptions that, combined with genius, patience and a lot of help from Poland, cracked the Nazi Enigma code. Without that, the war would have gone on for much longer—perhaps long enough for Hitler to get an atom bomb and win it.
He also portrays convincingly the bureaucratic struggles and intellectual snobbishness that surrounded the development of computing in Britain. Machines that seem to think prompted the same mixture of muddle and panic then that they do now.
Mr Leavitt does his best to explain the principles of both mathematics and philosophy, although it is probably impossible to explain the principles of advanced maths, cryptography and computer design in a way that is simple enough for even the most indolent reader to understand. Mr Leavitt's self-confessed lack of a mathematical background does not help his accuracy. Goldbach's Conjecture, a famous mathematical problem, for example, states that any even whole number is the sum of two primes. Mr Leavitt leaves out the word “even” which may have some readers scratching their heads as they reach for pencil and paper.
The author shows considerable sympathy with Turing's homosexuality and the difficulties he faced as a result of it; when convicted for “gross indecency” in 1952, he was forced to have oestrogen injections, a form of chemical castration that also, humiliatingly, made him grow breasts. He committed suicide two years later. By today's standards that was outrageous treatment. The author implies that this was exceptional. Sadly, in the climate of the day, which treated homosexuality as an abhorrent mixture of sickness and weakmindedness, rather as paedophilia is regarded now, it was not. To see him chiefly as a gay martyr is a mistake. Turing's life added up to more than that.