Maurice Wilkes on Alan Turing

Turing’s work was one of many key pioneers of his era. But our digitized world was not created by one man alone.  Peter J. Bentley  writes: Maurice Wilkes went on to become an enormously important pioneer in computing: building the first practical stored program computer in the world, and helping to create many designs for computer architecture and programming methods still used to this day. Sir Maurice Wilkes studied at Cambridge in the same course as Alan Turing, at the same time.  Unlike Turing, Wilkes lived 97 years. 1997 at an after-dinner speech at his old College in Cambridge Wilkes gave his  view about Turing’s contribution. Today these views seem controversial, but provide a fascinating insight into the history and rivalries within computer science, wrote Peter J. Bently (OUPblog-posted June 18, 2012) celebrating Alan Turing's 100th birthday. Wilkes talked about Turing:

“I found him reserved in manner, but the occasional encounters between Alan Turing and myself were entirely cordial. However on a technical level, of course I did not go along with his ideas about computer architecture, and I thought that the programming system that he introduced at Manchester University was bizarre in the extreme. I may have expressed my views rather strongly. Some admirers of Turing thought that perhaps I did not show the proper reverence for the great man. But why should I? We were exact contemporaries. We took the Tripos [a math degree in Cambridge] in the same year and as far as the class list was concerned we achieved exactly the same result. Jack Good [a colleague of Alan] said that Turing was a deep thinker rather than a fast thinker. His IQ was therefore not especially high. That description does I think apply very well to Turing. He was a colourful figure on the English computer scene in the early days of computing immediately after the Second World War. There are differing opinions about what his influence was."

“Turing’s work was of course a great contribution to the world of mathematics, but there is a question of exactly how it is related to the world of computing. There is no reference as far as I know that there might be a real machine as opposed to the one in the paper ["On Computable Numbers, with an Application to the Entscheidungsproblem"]. Suppose someone said to you, ‘In order to design an electronic digital computer, we must first explain and illustrate the working of the Turing Machine.’ What would you think? There’s no connection at all. At least to those of us who built them! "

“It raises the question of the status of theoretical work in the computing field. One view is that such work is really mathematics – its value is to be judged by mathematical standards. I am inclined to that view. On the other hand it can be, and is maintained by some, that there is a subject called theoretical computer science, which has its own standards

and its own criteria. It would have been interesting to have had Turing’s view on this question. He might have been severe on some of the computer science theory that gets published these days, but of course we do not know."  “There are subjects for which there is a mathematical basis, for example Maxwell’s equations provide a real basis for radio engineering. If you were going to design a radio antenna, then you better know something about Maxwell’s theory. The reason why it is a theory is because Maxwell’s equations encapsulate with them very neatly physical laws. They do tell you something about what the world is like. You can’t say that the automata theory [which describes theoretical computing machines such as the Turing Machine, used by theoretical computer scientists] forms the basis for computer science. In fact I myself do not find it helpful to regard it in that light. I would suggest there are two things in this world: automata theory and computer science. These things are level; one is not more important than the other. They exist side by side and there are interesting connections between them.

“Of course Turing also had a great interest in whether machines could think. I was thrilled by the paper he wrote in Mind ["Computing Machinery and Intelligence," which described the Turing Test to measure the intelligence of computers]. I have long felt that Turing, would, if he had lived, have come back to this question and I would have liked to have seen his views. A great deal has been written on Artificial Intelligence. Not all of it is nonsense. It could be that Turing with his prestige, his great insight, and his wit, it is possible that, had he lived, he might have restrained some of the excesses, which you see in that area. But alas he did not.”


Turing's electromechanical bombe machine, (c) Bletchley Park

Peter J. Bentley reminded, in addition to  the ‘strong comments’, of Wilkes some 50 years earlier, on the subject of Wilkes’ designs for his pioneering computer. Turing said the work was, “much more in the American tradition of solving one’s difficulties with much equipment rather than thought." But what about Turing's electromechanical bombe machines for cracking Enigma codes to locate German U-Boat submarines? Probably over 200 of these huge machines were built: isn't this also much equipment rather than thought ? (See the Bletchley Park picture of just one of those bombe machines.) But this my critics is desecration, since Turing is treated as a godhood. As the keynote speaker at a software engineering education conference in 1995 at Washington DC, David Parnas said "Turing is irrelevant". Because of this act of sacriledge he lost his job as a tenured professor. He went to Ireland to become a professor at Limerick. This is not a joke.