Alan Turing: the Enigma - Book Review

Alan Turing (23 June 1912 - 7 June 1954) was one of the most unlikely and yet most remarkable heroes of the second world war. A top Cambridge Mathematician whose expertise lay in mathematical logic and who crossed swords with Wittgenstein is unlikely to be an easy figure for the popular biographer, but Andrew Hodges, himself a lecturer in Maths at Oxford, is a match to the challenge.

Hodges neither shies away from expounding the complexities of the mathematical problems with which Turing was grappling in his pre- and post- war academic research, nor the inner turmoil of that he faced grappling with his [homo-] sexuality, which is a thread that runs throughout his life from School to his untimely suicide. At times when reading this book, one is conscious of touching on the secret world of the mathematician "this being the frightening subject of which even educated people know nothing" [p.239].

Turing's life impacted on three important areas of British society beyond the narrow confines of academe, although in all three areas his contributions were appreciated much more in retrospect than at the time. First, Turing is perhaps best known for his influential war-time role cracking the German U-boat Enigma cipher (1939-40) as part of the Bletchley Park code-breaking team. Secondly, he was the founder of computer science (1936) and was involved in the early development of the first computers, most notably as one of the first computer programmers at Manchester University, subsequently being made a Fellow of the Royal Society in 1951. Thirdly, Turing's prosecution for Gross Indecency contrary to Section 11 of the Criminal Law Amendment Act 1885 (1952) is in stark contrast to the way in which homosexuality is viewed today and highlights how far social attitudes have changed in the past sixty years.

This is by no means an easy read. The world of the professional mathematician is not particularly action packed - and the finer points of mathematical theory take quite a lot of getting your head around - so be prepared to be challenged. However, for those who take the trouble, this is a most rewarding book with unanticipated insights into a range of scientific, philosophical, technological and historical issues.