Alan Turing: The Enigma

This is a re-release of a book that was first published in 1983 (and largely researched during the 10 years prior to that), so it first came out in a very different time than today--a time when World WarII secrets were still being somewhat protected, and when the details of a homosexual man's life were still not easy to explain to the average audience without giving offense. Also, it was written and published in Great Britain. As a result, there are many allusions and off-hand references that are opaque to an American living in 2015.Although the author is a gay rights activist himself, as well as a mathematician, and wrote this book in part to try to see Alan Turing's life from a sympathetic point of view, some of his narration comes across as coy to the point of obscurity--he mentions Turing's trip to Sweden, but it is not till much later that it finally becomes clear that he went there to pick up young men. It is never completely clear which of his friends were also lovers and which were just colleagues. And perhaps that was necessary when those men were still alive, or were only recently deceased, but if the book is going to be re-issued, it needed to be re-edited as well. The intro, which details places where changes should or could be made, was not an adequate substitute for a revised edition.The explanations of code breaking is detailed, but perhaps necessarily obscure as well. I still have no idea of how Turing's insights were different than what the Polish codebreakers had already accomplished. One point that was a big issue in the movie, about how the Allies should use the information that they from their ability to read the Enigma code was never mentioned in the book, yet it is a crucial question--the movie has the military allowing a ship carrying one of the codebreakers's brothers go to its death, because otherwise the Germans would know that the Brits were able to read their messages, and would then change it. This is not in the book (fine, maybe it was fiction), but it's a key aspect of game theory--how do you use your hard-won information without tipping your hand? And if you can't use it, what's the point of having it?It is a bit ironic that a book whose title implies that Alan Turing himself is the biggest enigma manages to leave him still an enigma in many ways, but that is the case.I think the aspect of the book that I most grasped and that was the most thought-provoking was Turing's ideas about machine intelligence. Turing was not actually most interested in making machines that were intelligent; he was most interested in exploring intelligence in machine form in order to understand what human intelligence actually is. He posited an extreme statement: machines can (and will some day) do everything that human brains do. But his point was to show that there was no "ghost in the machine," no special non-material "spirit" or "will" or "intuition" or "insight" necessary to explain human intelligence.Like most people, I resist this idea to some extent. Could machines (computers, that is) ever make judgments? At first, my answer is no. But then they made computers that play chess at a Grand Master level (in the 1980s!). Ok, but that seems like a sort of a stunt. Recently IBM's Watson beat Ken Jennings and Brad Rutter at Jeopardy. Still, it seems more like looking things up on Wikipedia really fast, rather than actually thinking. But then I read that Watson is actually being used to diagnose illnesses, and that computers are more accurate than physicians, less liable to be led astray by forgetting or overlooking or dismissing crucial details. Hmmm, In advance, I would have said that the ability to diagnose a disease was an example par excellence of the sort of human judgment that computers would never have. And if they can drive our cars, and avoid accidents better than human drivers? Who would have thought it? Apparently the answer is, Alan Turing would have!One off-hand remark in the afterword is that the author wonders if some day, a computer will be able to write a book such as his. Unimaginable, I think. But my daughter reminds me that computers already compose news items (rather badly, but still.) And we discuss the possibility that a basic undergraduate research paper could be composed by a computer today, and I think the answer is Yes. I can imagine that one could teach a computer to write a paper that discusses Domestic Violence, pulling together statistics on its frequency, demographics,causes, effects on children, possible solutions, and so forth.I am left still puzzled by Alan Turing, finding it hard to picture him as a man, but deeply impressed by his mind, by his foresight and his insight, and I think that perhaps in some ways, he is in fact as significant a figure as Darwin and Einstein. What a tragedy that he died so prematurely, whether his death was in fact suicide, or possibly murder, or even more unlikely, a weird accident. How fitting and how odd that he died by (apparently) eating a poisoned apple. If it were fiction, it would just be too neat.

This was an excellent book about Turing, his life, his work, and his contributions. There was a lot of the technical aspects of his work which at times I had a little trouble following and it did slow down the book a bit. But still, overall I did enjoy it.

The book begins with the obligatory summary of his parents' lives and Turing's rather uneventful early years. It gets interesting when Turing gets to Cambridge, where he faces real intellectual challenges and starts on what was to be his major scientific accomplishment: the question known as “computability”. Hodges provides a very good discussion of this question and Turing's resolution, and how it lead to the concept of the Turing machine, a model that can be said to be implemented in all modern computers, but in no way serves as an ancestor of any of them.The real fascination of Turing's career (for most of the reading public) is his work on calculating machines to aid in the decrypting messages from the German Enigma machine used to encode their naval communications, most particularly with their submarines. The particular contribution of Turing was the design of the electro- mechanical device called the “bombe” (an anglicization of the polish “bomba”, for a prior device for a similar purpose developed in Poland based on even earlier work in France in the late 1930's, at a time when both these countries seemed more sensitive to the need for decoding German military communications than was England). Turing's bombe was an electro-mechanical device that efficiently replicated the action of several Enigma machines wired together. As used by the Germans, the rotors of the Enigma (which provided the random encryption) were reset each day. The challenge for the British was to twiddle the rotors in the array of bombe's until they got some rational looking text from an attempted decryption of the intercepted German messages. Most of the enormous number of possible rotor settings were generally reduced by screening out those that did not produce any of a frequently used set of terms (called “cribs”) anywhere in the message. Once a promising setting was determined, all the rest of the messages for that day could be decoded. The book provides extensive details of bombe operations and how they were applied.The book describes the roles of many individuals as the bombes were improved and their numbers expanded to operate at several sites in England (as a precaution against arial bombardment of a single site). While the book gives Turing the most important role in this process, it is nowhere near the “but for” importance implied in the movie “The Imitation Game”, which is loosely based on this book. The book describes several of Turing's unique contributions including his famous letter to Churchill, dated October 21, 1941, as an eminent scientist pleading for more funds to accelerate the Bletchley Park effort, Churchill's positive response may have made a significant difference in anti-submarine warfare at that time. Another unique contribution was Turing's visit to the United States from November 1942- March 1943, with his offering very perceptive guidance on the US bombe construction program (which eventually surpassed the British in numbers and speed of computation).Nearly half of the last 100 pages of the book is devoted to Turing's affair with Arnold Murray and his subsequent prosecution for it. The author reveals that he (Hodges) is also a homosexual, as if to prepare the reader for some insight on the matter. I would have appreciated some explanation of the fact that, although Turing had a number of sexual relations with men of his own age, class and intellectual attainments (described fleetingly in the prior narrative), he suddenly chose a working class man, less than half his age, with only modest intellectual yearnings and no accomplishments. [My own interpretation is that he wanted, consciously or subconsciously, to be a martyr and brought the whole thing on himself by going to the police to report a minor burglary connected to the affair.] As for the larger social significance of the situation, Hodges tries to build a case that Turing was especially prosecuted because it was perceived that his uncontrollability made him a serious security threat. This argument is not very convincing since Turing had done no security work for at least 5 years previous and had no prospect of doing any in the future. Furthermore, there is no evidence of any involvement by high government officials, only a few local police and prosecutors.I would advise skipping the rather lengthy introduction (31 pages) until after you've read the book; it doesn't introduce the subject, but does give some interesting tidbits of discoveries and re-interpretations since Turing's death. This subject is also treated in the Author's note at the end of the book.

Like a lot of people, I became consciously aware of Alan Turing from the film the imitation game and given a reasonable interest in history and social history, particularly ordinary people doing extraordinary things, I thought I would give this a go. This book is superbly researched and superbly written. Hodges is able to write detail in (the most part) an accessible manner, and I found about half this book fascinating. I particularly really enjoyed learning about Turing the person, whether that be at school, home, Cambridge, Bletchley, Princeton and his personality and aims. I also had some interest in his great contribution to computing as we now know it and his work. So, why only 3 stars? This book is full of some very heavy detail and about half of it is taken up with detailed maths, and when i say detail i mean pages and pages. In order m to understand any of it, I would imagine you would need to understand maths at degree level at least. However, if you have interest in Turing, i would recommend this just be warned...If you wanted to read the book of the film be aware, as it's harder going and the film's interpretation seems loose to say the least (as much as I enjoyed it)

When I saw that this book had over 700 pages my heart sank. Look, I want to learn the essential facts about the thoughts, influential life events, and achievements of Alan Turing. I don't want a catalogue of facts about his ancestors dating back 500 years. This book needed heavy editing. Congratulations to the author for doing the research. If that's what you wanted to present, a research monograph on Alan Turing, it should have been an academic publication. However, as a popular account of his life I'm afraid it has irrelevant detail that I quite frankly don't want to know. So now I'm looking for a shorter book that gets to the point quicker.

This book is not easy going, but you would expect that judging by the complex character it is based upon. For once I am extremely glad to have seen the film before reading this book, upon which the film is based. In that way I have been able to follow what is a very complex biography and dare I say, a bit boring in places.So why 5 stars? I have read more than my fair share of biographies over the years and in order for the author to receive their rightful praise and for the subject to be recorded, it is often appropriate for the author to leave no stone unturned and that is what I believe Andrew Hodges has done. I have no idea if he has missed anything out about Alan Turing's life, but from what I have read, this is a very thorough recording of this incredible man's life.It is very thought provoking and removed some of my stereotypical prejudices and hopefully by watching the film, visiting Bletchley Park and listening to his dad going on and on about what a hero Alan Turing was, I hope that my 14 year old son has learned that not all heroes are involved in brave acts and that as a nation we have much to be grateful to this truly wonderful man. It is sad that our "establishment" drove this poor man to suicide and thankfully my son is growing in a more liberal society than the one that I grew up in as a child and therefore I would hope that we never persecute a man to the depths of despair and then sought to erase his achievements from the nation's history. Well done Andrew Hodges; I would like to see an abridged copy prepared for schools, not only would it allow children to see that not all heroes wore rows of medals, but that there is a place for everyone in our society whatever their views or persuasions.

A brilliant book, beautifully written with meticulous and exhaustive research. It presents a portrait of Turing very different from the autistic-genius-scientist stereotype offered by the film The Imitation Game, which claims to be based on this book. Quite how that basis worked I'm not sure as the film shows a Turing who doesn't know what a joke is and seems unable to grasp the function of humour at all, whereas this book is full of instances of his humour, often engagingly silly. It also does what no film could be expected to do, which is present his ideas in detail (too much detail for some, apparently.) The book gives readers a chance to get a handle on an extraordinarily intense and original intelligence which not only played a critical role in Britain's wartime history but was reaching into the future possibilities of maths in very strange ways - for example working out formulae to reveal the patterns that leads to the markings of animals such as zebras.

The story of Alan Turing is a sad one, but his work and his memory live on and he's now belatedly given the credit he deserved.The story of the enigma doesn't just involve Alan though, there were a lot of other people involved, not least of all he used the work started by code breakers in Poland to create his own method of breaking enigma.If you've watched the movies, the documentaries or had the good fortune to visit Bletchley park then this book is fantastic for learning more about the man.