A Man of Machines

Alan Mathison Turing

Article A Man of Machines

The world celebrates the hundredth anniversary of Alan Feature Feature Turing who laid the foundation for the ‘intelligent machine’

MANAS PRATIM DAS

T is extremely unlikely that Adolf Hitler knew about a British mathematician Icalled Alan Mathison Turing but had Hitler somehow known the fellow he could Dip the apples in the brew, have identified one more factor that led Let the sleeping death seep to his downfall. War historians might scoff through… at giving too much importance to an Alan Mathison Turing individual in deciding the outcome of the committed suicide on 8 June Second World War. 1954. His body was discovered But they would be uncomfortable in with an apple lying half- ignoring the role Turing played in cracking eaten beside his bed. the codes created by the mighty German Enigma machine. Surely, breaking the Enigma code is not the only contribution that Turing made in his lifetime but it was This course and the associated stream that it had set superior standards in certainly the most important from the of events finally led him to Bletchley Park. encipherment. historical viewpoint. Whatever it meant to lay citizens, Bletchley Alan Turing returned from America to Park, after the autumn of 1939, had The Machine his homeland England in the fall of 1938 become the address of Britain’s core At the end of the First World War the after having turned down an offer to work group of codebreakers. The German decimation of Germany began through as John von Neumann’s assistant at blitzkrieg that was conquering countries at the Treaty of Versailles. It was an unjust and Princeton. In June of that year he had a very fast rate had to be thwarted. The highly biased treaty where the victorious earned his PhD with a groundbreaking Allies, of which Britain was a part, knew that Allies put all the blame on Germany and dissertation titled Systems of Logic Based their best bet lay in cracking the secret made it pay heavily for the damages. But on Ordinals. German code that was making German deep inside the German psyche there Back home, he was recruited to join military progress possible. remained an anguish and zeal to avenge a course on cryptography and Communicating through secret this injustice. The Enigma machine can be encipherment sponsored by the ciphers or codes had been in vogue since thought of as being a product of this Government Code and Cipher School in time immemorial. Every major user had mentality. London. The school’s director Alastair tried to make his code more complex so Electrical Engineer Arthur Scherbius Denniston had heard about Turing’s that it became unbreakable. But in every designed this machine to replace the exceptional mathematical ability and was age a solution had somehow sprung up. inefficient systems of cryptography used keen on having him among his students. And therefore, no code had been in the First World War. It will be wrong to Turing understood the need and was willing absolutely secure. The Enigma code did term his effort as ‘all patriotism’ and ‘no to help. succumb to this age-old rule but before profit seeking’ because he had made all 31 SCIENCE REPORTER, APRIL 2012 Feature Article

Breaking the Enigma code is not the only contribution that Turing made in his lifetime but it was A slate statue of Alan Turing with the famous Enigma machine certainly the most important from the historical viewpoint.

necessary arrangements to rake in profit As Simon Singh puts it in his bestseller set up a secret bureau mainly with the aim through the sale of his innovation. He The Code Book, “Over the next two of cracking Enigma codes. The genius founded a company with his friend Richard decades, the German military would buy who led the mission was called Marian Ritter and took out a patent for his over thirty thousand Enigma machines. Rejewski. machine. Scherbius’ invention provided the most Over the years Rejewski built up an It was a formidable cipher machine secure system of cryptography in the elaborate system to decipher Enigma that combined electrical and mechanical world, and at the outbreak of the Second codes. His major achievement lay in parts. However, the person in charge of World War the German military’s discovering the method for finding the key encrypting a plain text message for communications were protected by an for encipherment. The Germans changed onward transmission was not required to unparalleled level of encryption”. the key everyday or even sometimes once know the structural intricacies of the in a few hours and it was the heart of machine. He could just type the text on Attempting A Break encipherment. Rejewski kept pace with the the keyboard of the machine and receive Germany’s neighbours and its adversaries German military as they made changes a jumbled collection of letters in return. could not sit idle and watch Germany’s to the machine in order to make the That was the coded message. The receiver, secret communications go from strength encoding a more complex process. in turn, had to type the apparently to strength. They had to do something in By 1938, the Poles were at the peak meaningless code on the keyboard and order to ensure their safety in the years of their code breaking success. But then a voila, he saw the meaningful text message preceding the Second World War. But host of changes at the German end in front of his eyes. apart from discovering a traitor in the form rendered their setup insufficient for the Thus, from the user’s point of view it of Hans-Thilo Schimdt who supplied the process of code breaking. It was at this was very friendly and therefore design of the Enigma machine, the French point that the Poles invited the British and commercially successful. Once the could achieve nothing in this regard. French cryptanalysis and sought their help. machine was made robust and its Poland, however, was desperate to They handed over their technologies and usefulness established the German military gather information regarding Germany’s made a fervent plea to carry on with the placed heavy orders for its purchase. In communications. It had gained process. Everyone could sense that a big 1925, Scherbius began mass production independence in the aftermath of the First war was approaching and the British of his machine for supply to the military World War but was afraid that Germany marshaled its strength to take up the forces. might any day lay claim to its territory. They Enigma challenge. SCIENCE REPORTER, APRIL 2012 32 Feature Article

Every major user had tried to Alan Turing's office at Bletchley Park make his code more complex so that it became unbreakable. But in every age a solution had somehow sprung up. And therefore, no code had been absolutely secure. Cracking it at Bletchley On 4 September 1939, Alan Turing reported to Bletchley Park. It was actually a massive building in Buckinghamshire, about fifty miles northwest of London. Admiral Quex Sinclair had bought the house to serve as the base for the functioning of the General Code and Cipher School. It was undoubtedly a center of military activity but the group that arrived there, Turing decided that more developed machines especially in a mathematics paper in the included, had very little respect for formal had to be built to crack the Enigma codes. 1930s, was to break the rules of a fairly behavioural manners. Turing was the one who designed a rigid orthodoxy. No such machines existed There were mathematicians other new generation of bombes. Back in at the time, only calculating devices too than Turing. Two of them were fellow Princeton he had built an electronic crude to undertake any complex Cambridge mathematicians namely multiplier that could encipher messages mathematics, and certainly not Gordon Welchman and John Jeffreys. by multiplying large binary numbers programmable.” Leavitt is only correct There was another called Peter Twinn. Apart together. So he was the really experienced when he writes in such a manner. from mathematicians the team had one in this regard and the responsibility fell G.H. Hardy, the famous number experts from other areas of knowledge on his shoulders. theorist, had earlier summarily dismissed also. Hugh Alexander, the British chess In fact, Turing had been in love with the proposition of mathematicians making champion was there alongwith the writer machines all his life. In 1937, about a their discoveries by turning the handle of a Malcom Muggeridge. The military couple of years after he was elected a miraculous machine. Hardy simply establishment had also ensured the fellow at King’s College in Cambridge, represented the views of his peers. But services of winners in a competition to solve Turing saw his revolutionary paper come Turing was a different breed altogether and the Daily Telegraph crossword puzzle as fast out in the Proceedings of the London thus he could say at one place in his paper: as possible. Mathematical Society. It was titled “On “According to my definition, a number is The mathematicians staying at a low Computable Numbers, with an Application computable if its decimal can be written building called the Cottage first to the Entscheidungsproblem”. In it Turing down by a machine.” concentrated on the techniques of code proposed to build a machine that would Turing’s bombes kept the British breaking invented by the Poles. Rejewski determine the solvability of the classical armed forces informed about all the and his team had built machines to aid Entscheidungsproblem or the decision German measures. As Turing and his their effort. Those were called bombes. problem. To propose such a step needed colleagues built on their successes the Several explanations existed as to why it sheer courage and radical thinking. British could anticipate every attack from was so named with no particular one As David Leavitt explains in his book the German end. When Turing eventually claiming to be the correct one. The British The Man Who Knew Too Much, “To speak cracked the naval Enigma code of the establishment retained the name but of a hypothetical computing ‘machine’, Germans it spelt doom for Hitler’s war efforts. Immediately there was a sharp decrease in the number of Allied ships sunk by German U boats. One might question the correctness of awarding all the credit of these successes to Turing alone. However, historian Stephen Budiansky puts all such doubts to rest by stating that “the fundamental mathematical insight behind the British bombe was wholly Turing’s”. In his book Battle of Wits: The Complete Story of Codebreaking in World War II he gives a Commemorative stamps on Turing neat and vivid description of Turing’s 33 SCIENCE REPORTER, APRIL 2012 Feature Article

In fact, Turing had Turing was elected fellow at been in love with King's College in Cambridge machines all his life. In 1937, about a couple of years, he was elected a fellow at King’s College in Cambridge.

method that later came to be known as from the German end. But his heart was Banburismus or more generally as yearning for more. Turingismus. Alan Turing wanted to build a machine Turing in 1927 Andrew Hodges, the biographer of that would be more general in nature, not Alan Turing, underlines his prominence at like the ones he had dedicated to Bletchley Park with these words: “By 1942, cryptanalysis. His travel to the United States Alan Turing was the genius loci at Bletchley in November 1942 as part of the Park, famous as ‘Prof’. There could be no decipherment programme helped him a lot. The Bell Labs nourished him with fresh by Sir Geoffrey Jefferson of the Department ideas and Claude Shannon of MIT shared for Neurosurgery at the Manchester his own romanticism of building a machine University started attacking the Manchester that would understand the recital of poetry. computer. In fact Jefferson had drawn his In June 1945, Turing joined the ideas from the American Norbert Wiener National Physics Laboratory at Teddington, who is called the Father of Cybernetics. which is a suburb of North London. As one His book Cybernetics released in 1948 had of the premier institutes of Britain it was stirred the whole world and introduced engaged in the task of catching up with new thoughts about intelligence of Block B America’s progress in computing. In that machines. very year two large computing machines, Wiener was fond of Turing and paid a ENIAC and EDVAC from America had set visit to him in the spring of 1947. Having debate over his contribution to the victory the trail blazing. Now Turing had a real learnt this Jefferson concluded that of the Allied Forces in the greatest battle challenge in hand. Newman and his colleagues at fought on this planet.” He presented his plans to the Manchester were actually up to building However, Turing and all other inmates authorities of the institute of building a machines that would compete with human at the Bletchley Park received no official machine that would be called ACE, short beings. He painted this effort in a light that recognition after the end of the War for Automatic Computing Engine. He suited the gibberish of a popular media because cryptanalysis has always been a insisted that his machine would be a digital and the Times was very quick to take clandestine activity and thus Bletchley’s one and it would ‘learn’ by experience. advantage. It aroused public sentiment achievement remained a closely guarded Unfortunately it ran into competition with against Newman’s machine. But Jefferson secret even after 1945. It was not until 1974 another machine proposed to be failed to realize that Newman’s team was when Captain F.W. Winterbotham obtained developed by his former classmate far from building a robust computing permission from the intelligence services Maurice V. Wilkes. As history would have it, machine, let alone enriched with human to write a book on the codebreakers that the soft-spoken Turing was finally nudged intelligence. the deserved recognition finally came out of the programme though the Pilot ACE However, not all was in vain as far as through. was finally built after a fashion. the Baby or Manchester Mark 1, as it was In 1948, Turing moved to Manchester later called, was concerned. Thirty-four The Real Turing University at the invitation of Max Newman. patents resulted from the machine’s Turing started to remove himself from the There, as Leavitt says, “The machine on development, and many of the ideas intense activities at Bletchley Park by the which Turing went on to work was a behind its design were incorporated in middle of 1942. There was no dearth of preliminary model intended for small-scale subsequent commercial products such as work, of course. Max Newman, his mentor experiments, and thus christened (in the IBM 701 and 702 as well as the Ferranti at Cambridge, had arrived to take care keeping with Turing’s educational Mark 1. The Manchester Mark 1 continued of the Fish traffic, which was a stream of program) the Baby.” to do useful mathematical work between codes enciphered on a teleprinter. He Though it became operational in 1949 and 1950, including an investigation contributed, even if in a small way, to the June 1948 it was an extremely difficult of the Riemann hypothesis and building of the Colossus that would machine to handle. It ran into more calculations in optics. effectively decipher the Fish traffic flowing difficulty when the media riding on a lecture SCIENCE REPORTER, APRIL 2012 34 Feature Article Turing took an intense liking to the On His Centenary… film ‘Snow White...’ and would keep Though Alan Turing was born in Maida Vale, reciting lines from it. London on 23 June 1912 he was actually conceived in Chhatrapur of Orissa in India. life is no wonder when we consider his His parents moved to England, as they zealous attempt at integrating man and wanted their child to be educated in their the machine. homeland. We can vaguely be proud of Snow White and the Seven this Indian connection during his centenary Dwarfs celebrations. As ordinary world citizens we might The 1937 animated version of the Snow also ponder over what he could have White and the Seven Dwarfs produced by achieved if left to grow normally into a Walt Disney was released in America in mathematician like G.H. Hardy. He was But Turing was inextricably engrossed 1937 but its British premiere took place in different from Hardy in the sense that he in his idea of building intelligent machines. the following year. Turing took an intense wanted to make mathematics ‘useful’ In October 1950, his paper titled liking to the film and would keep reciting which Hardy abhorred. To him reality ‘Computing Machinery and Intelligence’ lines from it. While it might be overtly mattered as he had curtly told the Austrian appeared in Mind. While Wikipedia like melodramatic to mention his chanting of many others calls it a ‘seminal paper’ Leavitt two particular lines from the film as he had termed it as Turing’s ‘most perverse walked through the corridor of King’s at paper’. Cambridge, it is difficult to resist the In it Turing counters every objection temptation. The lines are: to an intelligent machine in his own inimitable style. He even takes on the Dip the apples in the brew, theological challenge saying that he is Let the sleeping death seep through… ‘unable to accept’ the theory that “Thinking is a function of man’s immortal soul. God Alan Mathison Turing committed has given an immortal soul to every man suicide on 8 June 1954. His body was and woman, but not to any other animal discovered with an apple lying half-eaten or to machines. Hence no animal or beside his bed, and although the apple machine can think.” was not tested for cyanide, it is speculated He puts forth his conviction in the that this was the means by which a fatal concluding paragraph in these words, dose was delivered. Turing had taken the Alan Turing was actually conceived in Chhatrapur of “We may hope that machines will two ominous lines to his end. Orissa in India. His parents moved to England, as they eventually compete with men in all purely It was not a sudden suicide. Without wanted their child to be educated in their homeland. intellectual fields.” In this very paper he going into the details that have been written introduced the Turing Test that determines many times since his death it is enough to philosopher Ludwig Wittgenstein who was a machine’s ability to exhibit intelligent say that he was charged with totally against creating an interface behaviour. This single paper can explain homosexuality under the Criminal Law between pure logic and real why Wiener was so fond of Turing and why Amendment Act 1885. Homosexual acts circumstances. Alan Turing shares the honour of being the were illegal in the United Kingdom at that He was extraordinary in tackling the father of Artificial Intelligence with Norbert time and so he was charged with gross decision problem or Wiener. indecency. Turing was frank about his sexual Entscheidungsproblem with a Turing That he would go ahead to work on behaviour but he had to accept the machine. A point may come when all his mathematical biology especially consequences. extraordinary attributes along with his morphogenesis for the last two years of his He was given a choice between truthfulness and romanticism might gel into imprisonment or probation conditional on a surreal mix in our minds. That is the his agreement to undergo hormonal perfect time to remember his epitaph treatment designed to reduce libido. He where is written: accepted chemical castration via oestrogen hormone injections. As Hodges Hyperboloids of wondrous Light writes, “Once arrested, Turing was turned Rolling for aye through Space and Time into a class traitor and cold-war risk in the Harbour those Waves moral panics and national security crisis of which somehow Might 1952. Amidst this, for him the issues of truth Play out God’s holy Pantomime and trust were paramount. Turing believes machines think, Turing lies with men, Therefore machines do not think, he wrote, Dr Manas Pratim Das is with AIR-Kolkata. Address: camp humour combined with 52/1, Adjacent to Ramkrishna Pathagar, Netaji mathematical camp, but with truth at the Subhash Road, PO New Barrackpore, Kolkata centre.” 700131 35 SCIENCE REPORTER, APRIL 2012