Alan Turing

The Turing Machine is a well-used term, yet is largely unknown outside of the world of computer science. Alan Turing, the renowned mathematician suffers from the same fate as his namesake of being an unknown scientist in the eyes of the general populous. Despite the unfamiliar name and creations, Mr. Turing’s 95th birthday recently passed providing an opportune time for an award to be given to Alex Smith of Birmingham, UK for the smallest Turing Machine ever discovered. Yet in today’s modern age, the smallest Turing Machine is a small step with little fanfare. Alan’s inventions and life are less than a century old and despite being unknown, they have a major impact on most aspects of computers as we know them. Who was Alan Turing, what is a Turing Machine, and what does the machine have to do with computers?

Alan Mathison Turing, Born June 23, 1912 in a nursing home in Paddington, England to his father Julius Mathison Turing, mother Ethel Stoney Turing, & 4yr old brother John. Despite his father being an ICS official in British India, Alan never saw the Middle East. He also saw little of his father, living mostly with his mother and brother.

Shortly after birth, the First World War kept Mrs. Turing and her boys in England and despite being too young for school Alan’s ambitions drove him to teach himself to read and began to appreciate figures and problem solving. With his advanced attitude toward learning Mrs. Turing chose to get him into the system early and sent him off to a private day school named St. Michael’s to learn Latin. After a short couple of years, at ten years of age, Alan was deemed a genius by the headmaster at St. Michaels and he was sent to Hazlehurst primary school like his brother. It was here at Hazlehurst that Alan was first greeted with organized classes, culture, and regime that would haunt Alan for the rest of his life.

The regime that he found at these schools also gave him a place to learn to work around the system and allow him to progress easily with his talents and his parent’s money to Sherborne Public school in 1926. At fourteen years of age, Alan chose to deal with the ongoing tradition of English public school by withdrawing and taking to learning math and sciences in his spare time. His highly capable status became unnoticed, his math and science skills left un-nourished by the system that was trained to ignore these skills. Despite this lack of nourishment and his withdrawal, it was at Sherborne where Alan both discovered himself and was inspired to explore the unknown. He fell in with a crowd of other semi-withdrawn science types and discovered that he had strong feelings for one of the boys. Christopher Morcom in particular held his interest and gave him the feelings in return. His relationship with Christopher Morcom inspired him to learn and dabble in sciences that were previously unknown to him. Astronomy and Electricity entered his purview as he tried to get on the same level as Christopher.

Christopher led Alan down the path of concocting a number of in-depth experiments that were at a university level. Alan of course with his knack for science and messy style both impressed everyone with his results and disappointed everyone with his poor documentation and record keeping of the projects. All of his projects became an effort to impress Christopher and despite this effort Alan was unable to produce anything important and presentable enough to get his most desired scholarship at Trinity College, Cambridge where Christopher would be attending. Instead he took his second choice of King’s College, Cambridge a year later in 1931. By 1935 he was elected as a fellow at King’s College and only a year later in May of 1936 he submitted the one paper that would change his place in history and the world, “On Computable Numbers, with an application to the Entscheidungsproblem”. This was clearly an example of his extreme insight and vision in computing. His withdrawal and general distaste for the rigmarole that continued to plague his academic experience did not get in the way of his ground breaking discovery. This paper finally achieved a level of grandeur that would have impressed Christopher, yet the paper came too late; the love of Alan’s youth had passed away before the paper was published.

 The paper itself used a logic machine to examine David Hilbert’s Entscheidungsproblem. The logic machine, later referred to as a Turing Machine, proved that the Entscheidungsproblem is not possible (meaning that it is not possible to algorithmically decide if an arithmetic statement is true or false). Alan’s paper and his machines were an example of this problem that would drive Alan through most of his Mathematical career.

With Alan driving into new paths of largely undefined mathematical branches (after all computer science did not exist as a possibility in 1936), he quickly rose to notoriety and by the 23rd of September 1936 was off to the United States to study math and logic with Alonzo Church (who had published a paper, proving the same thing as Alan, but in a different way) and the other prominent mathematicians gathering at Princeton. This trip to Princeton was his first of many trips to the United States and provided a good foundation for future returns to the states with a variety of agendas. He stayed at Princeton through 1938 obtaining a Ph. D. before going home to Cambridge.

Upon returning to England, Alan returned to King’s and began to work with the German Code and Cypher School on a part time basis. His thinking was that the government would probably have a use for his skills in math and logic as an application to code breaking. Of course World War II started shortly after that and Alan was ready to report to the Cypher School’s Bletchley Park on a full time basis, putting his fellowship at King’s on hold.

At Bletchley Park, Alan performed a number of critical roles. He relied on his previous ideas that were expressed in Computable Numbers and inspired the idea that the system being used to attack the German Enigma machines could be automated further. Basing their work on the information England acquired from Poland, Alan and Gordon Welchman devised what would be known as the British Bombe. The Bombe itself was based on the fact that when the Enigma was configured in a specific state, the letter “A” would be translated in the Enigma to the letter “G”, given that translation, the letter “G” would in turn be translated to letter “A”. The Bombe was used extensively and became one of the critical factors in the rapid success of the English code breakers. Alan followed up his success with the Bombe by becoming the head of Hut 8 where he continued to refine the process used to capture cribs (pieces of text that were known so that an entire message could be cracked) while focusing on the enigmas used by the German Navy.  By 1941, Alan had handed over the reins of hut 8 to a more experienced manager so he could continue to focus on the technical details of cracking the German codes.

Alan not only found interesting problems to work on at Bletchley Park. He found himself surrounded by intelligent men and women where he enjoyed a social life like he had not experienced before. He became attached to one of the intelligent people like he had previously done with Christopher Morcom; however, this time the attachment found itself with a women named Joan Clarke. Again a fellow mathematician and a person who introduced Alan to new mathematical wonders such as the Fibonacci numbers. Alan pursued Joan going through a brief engagement yet holding no hard feelings with her after calling off the marriage.

After his bout with Joan, the game at Bletchley began to change as the Fish came to use by the Germans and a new cracking machine (the colossus was needed). Alan was leveraged for his experiences in America being sent over in 1942 as an emissary to joint code breaking projects. His trip included unprecedented access to Bell Labs, MIT, and RCA where he worked on a series of classified projects making unknown contributions and learning unknown wonders of the still undiscovered world of computing. His work in America also included negotiations on where and how joint encryption projects between the United States and England would be worked on. Alan’s brief trip to the United States (November 1942 through March 1943) changed the way our two countries worked together to decrypt German codes as well as inspired Alan’s next leg of work.

On returning to England this time, Alan was refreshed with his brain swirling with new ideas of voice encryption and automated systems. His work was again out of the normal bounds of mathematics, encryption, and cultural norms; Alan found his way to Hanslope Park. Even here though, Alan’s quirky unkempt attitude was looked on with a disapproving eye. It was also here that Alan worked out portions of his Zeta-Function calculator and where he created his system named the ‘Delilah’. Both of these pieces of work carried no major significance on their own, yet the relationships, mechanical skills, and ideas he built proved to be priceless in the coming years when the computer was created.

The Electronic Numerical Integrator and Calculator (ENIAC) was the first of the major undertakings in modern computing. The ENIAC designed by J.P. Eckert and J Mauchly was based on the design of Charles Babbage and was near the ideas that Alan Turing had for a computer. The ENIAC differed in the details of what was required to program the computer, what kinds of information were stored, and how the instructions were managed. Alan’s design was similar to what we know as a computer today and was known as the ‘ACE’. The main difference was that Alan’s ACE was designed to have a single hardware configuration and a dynamic set of programming. He wrote:

“Instruction tables will have to be made up by mathematicians with computing experience and perhaps a certain puzzle-solving ability. There will probably be a good deal of work of this kind to be done, for every known process has got to be translated into instruction table form at some stage.”

This insight was more visionary then Alan could have realized. He definitively predicted how an entire industry would be created and transform the world in the process of thinking through the operational impacts of his small invention. He not only accurately predicted the important aspects of the computer but he also predicted the important considerations in operating a computer. Looking even further into Alan’s unexpected Insight into computing, Alan proved himself able to see the operational evolution of computers. He wrote:

“The masters are liable to get replaced because as soon as any technique becomes at all stereotyped it becomes possible to devise a system of instruction tables which will enable the electronic computer to do it for itself. They may be unwilling to let their jobs be stolen from them in this way. In that case they would surround the whole of their work with mystery and make excuses, couched in well chosen gibberish, whenever any dangerous suggestions were made. “

By the time Alan was thirty-five he resumed his King’s fellowship, it was 1947 and he had a legacy behind him already. He had contributed so much as a code breaker, a creator or the computing industry, and as a mathematician. He now was back to his fellowship and began to pursue his homosexual endeavors more heavily. His endeavors would continue, but in 1948 he moved from King’s to Manchester and began to pursue other academic interests. He leveraged his computability expertise to investigate physiology and how the human brain worked.

His time at Manchester would cross the gamut from preaching his last sermons on computing, programming, and operations to nearly improving the field of physiology. His personal life would continue to wind a web of personal endeavors and eventually legal reprimand for those endeavors. The legal reprimand that was due to his orientation and the illegality of homosexuality would cause a major effort on his part to ensure all of his friends, family, and colleagues were aware of his situation. Though he remained accepted by them and maintained his rank in the Order of the British Empire and in the Fellows of the Royal Society; he was reprimanded nonetheless, and received a sentence of probation for one year.

During probation Alan was permitted to stay at Manchester and continue his research and occasional instruction. He continued this research for a year after his probation had expired before being found dead at his home having eaten a poisoned apple like snow white. At the time the speculation of what really happened was light; although, it increased with time. The theories have ranged from simple suicide, to retaliation from ex-lovers, to British government plots to ensure the un-trustable homosexual confidants were kept permanently quite.

The Turing Machine may not be well known for what it was or how much of modern computing is based on the same principles, but most of society can appreciate the fruits of Alan’s labor in a wide number of ways. His basic contributions at such an early stage have influenced computer designers, programmers, and cryptographers all over the world. His contributions had insight far further than most people have in any one area of our world.

Works Cited

“Alan Turing.” Wikipedia. 15 11 2007 <>.“ENIAC.” Wikipedia. 15 11 2007 <>.“Entscheidungsproblem.” Wikipedia. 15 11 2007 <>.Hodges, Andrew. Alan Turing: The Enigma. New York: Walker and Company, 2000.“Turing Completeness.” Wikipedia. 15 11 2007 <>.Wolfram Science. 2007. 15 11 2007 <>.

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