Apple Macintosh's icon logo with its partially bitten apple, is said by many to be a visual allusion to Alan Turing, his tragic early death with all its conspiracy theories and one of the few actual recognitions of his place in our modern world's ubiquitous technology, the computer. A star of Bletchley Park, the WWII code-breaking group without whom many creditable historians claim the Allies would not have won the war and on whom Churchill depended a great deal, he was a brilliant, if eccentric, intellectual. (I often wonder at the strange view and desire of many people who must reduce the brilliant and extraordinary individuals to the ordinary, one minute expecting their brilliance but unable the next to cope with their differences and, of course, not all their ideas are brilliant.) He cycled with his gasmask on to avoid hay-fever, from which he suffered a great deal, and chained his tea-mug to the radiator to ensure it was there when he wanted it; he also cracked the Enigma-code and built and pioneered the use of an early computer to do it faster to speed the end of the war. Like many of Bletchley Park's darkest(?) secrets, he became inconvenient after the war and his homo-sexuality opened him to possible blackmail. Turing's brilliant ideas and philosophies are explored in reasonable depth in this brief, well -researched volume. For anyone interested in this fascinating genius, this is a good beginning.