Alan Turing: The Enigma The Centenary Edition

by Andrew Hodges

  There was another uncertainty in his attitude to the privilege of being a man in a male-dominated world. In most ways he took it entirely for granted. It was a weak point of King’s liberalism that it rested upon wealth accumulated for the benefit of men alone, and he would have not been the person to question it. In conversation with Robin, who took a progressive line on the question of equal pay (the only issue, in this period, which kept feminism alive), Alan said simply that it would be unfair if women were off work having babies. Nor did he doubt that women would run round him clearing up the mess, and seeing to matters that he chose not to bother about himself. In conversation with Don Bayley at Hanslope he mentioned how he had been engaged, that he had realised it ‘would not work’ because of his homosexuality, but also remarked that if he were ever to marry, it would be to someone non-mathematical, who would look after his domestic needs – a conventional attitude much closer to his family’s, and untrue to the way in which his friendship with Joan Clarke had developed. There was an unresolved contradiction here, at least at that stage of his life. He disliked the talking-down and triviality expected of men in ‘mixed company’ – and, no doubt, too, the pressure on him to display an erotic interest he did not feel – and largely avoided such social obligations. Yet when these constraints did not apply – especially, perhaps, with Lyn Newman, but to some extent with his own mother – he showed a mind more open to the other sex than that of many men to whom the word ‘women’ was a synonym for sexual possessions or distractions. Nor did he ever do more for male supremacy than to share in its institutions. He never sought to justify his homosexuality in terms of preferring the superior male, for instance, and when set against the speech and writing of what everyone called the age of the common man, his comments were remarkably free of the stream of hostility, implicit or explicit, than most men felt entirely free to direct at the encroachments or pretensions of women. Alan certainly spoke of ‘girls’ doing the menial work, and by implication cast them in the role of ‘slaves’ at Bletchley; yet this was simply the way things were, and if anything he was just a little more conscious of the inequity than were others who took it entirely for granted. He did nothing to change it, but then he had never sought to change the world, only to interpret it.

  He was not an Edward Carpenter, who saw a link between the low status of women and the stigma attached to his homosexuality. It would probably never have occurred to him that his own difficulties with the world were very akin to those suffered by women – as with the men’s committee meetings held over his head, almost as if he were not there, and the way that people took little notice of what he had actually said or written, but remained obsessed by details of manners or appearance. Women had to learn to compensate for these indignities by making a special effort, but Alan Turing made no such attempt. He expected the male world to work for him, and was baffled when it did not.

  He saw himself as a man doing a man’s job in a man’s world, and so far more conscious and definite, for him, was the fact that his love relations and power relations lay alike within that world. In this respect Alan Turing took most of the parts that society allowed – comic, tragic, pastoral, exile, outsider, in-between, and finally that of victim. But had also risen above these roles, not only by avoiding the usual lying and cheating that went with them, but by doing the one thing that a homosexual should never, never do: becoming responsible for something that mattered. He also refused to be daunted by the unsympathetic ambience of the technical world. (Indeed, it was a kind of attempted love affair in which – as usual – he was firmly rebuffed.) His move to Manchester, for instance, might well have held a conscious rejection of the temptation to remain in the ‘lovely backwater’ of King’s. Yet in that very determination he illustrated a problem which in the 1950s had hardly begun to emerge into consciousness: that in refusing social definition by a ‘pansy’ or ‘aesthete’ label, there lay the opposite danger of merely accentuating the accoutrements of ‘masculinity’. His running, although it spoke of a search for wholeness, for another life earned independently of being ‘a brain’, and for relief from the aggressive feelings induced by a lifetime of banging his head on a wall, was perhaps touched by this. So too, perhaps, were his emotional reserve, his all-or-nothing response to difficulties, his insistence upon professional ‘thinking’ before off-duty ‘feeling’ – all influenced by a resolve not to be ‘soft’. Yet soft machine he was.

  The confusion and conflicts that underlay his apparently single-minded homosexual identity reflected the fact that the world did not allow a gay man to be ‘ordinary’ or indeed ‘authentic’; to live simply, without making a fuss; to be truly personal, without taking a public stand. He, of course, was put particularly acutely on the spot. In 1938 Forster had spelt out the corollary to the claim for moral autonomy65: ‘Love and loyalty to an individual can run counter to the claims of the State. When they do – down with the State, say I, which means that the State would down me.’ But Forster never had to face this consequence, no more than Keynes was ever found out. It was Alan Turing, not as a King’s intellectual, but as one of thousands of un-famous people, who had to resolve a moral crisis almost in silence, and almost alone. But even if the events of December 1951 had never led to that particular crisis, the contradictions might well have come to a head in some other way. There was no such thing as ‘simple’ life for him, no more than there was a ‘simple’ science. Bletchley had proved G.H. Hardy wrong about pure mathematics; nothing was pure, and no one could be an island. Alan Turing might be Valiant-for-Truth, but even he had been led into the work of deception by science, and by sex into lying to the police.

  The yellow brick road divided, and there were no signposts provided to say which was the true and which the imitation path. But the uncertainty in Alan Turing’s life, the wavering between parts that struck observers most forcibly was seen not so much in terms of class, professional status, or gender, but in his oscillation between an ‘adult’ and ‘child’ role in life. To some people this was repulsive, to others an element of charm. While to some degree people used the word ‘childish’ to rationalise their surprise at a person who actually said what he thought, with little decoration or concealment, there was also something quite specifically odd about his manner, which became more noticeable in his late thirties at Manchester. A man with a quite powerful build, yet with the manners and movements of an ‘undergraduate’ or ‘a boy’, he was also disconcerting in his rapid changes of mood, between forcefulness and naivete, bristling with silent fury, but then breaking out in earnest charm. ‘Mercury’ was Lyn Newman’s image, linked with his running. It was an ambivalence with meanings at several different levels – an intellectual level in his refusal to be defined by his existing reputation, breaking instead into an entirely new sphere of work when approaching forty. And of course it held an erotic meaning, part of his response to the situation of homosexual men in general, in which the roles of seeker and sought were more fluid and diffuse than in heterosexual relationships. He had to keep moving; to keep on the go. These factors might indeed contribute a tension (though also a sheer fascination with life that others lost) as he became older. But beyond these meanings the boyman quality of Alan Turing also reflected that most central question of his existence, one more special to himself. He had not wanted to ‘come of age’ at twenty-one, and as it transpired, he just avoided seeing the age of forty-two. He had never wanted to take on the power of adulthood, although he did not shirk all of its commitments. He was at the opposite pole from John von Neumann, although their brains touched so many common points. A master of committees, and a consultant to every American military organisation, with particular responsibility for the hydrogen bomb and the intercontinental ballistic missile, von Neumann in 1954 was a man of the world who dominated, and was not dominated by, his adopted country.* Alan Turing, in contrast, though born into the heart of an immensely confident administrative class, had only forced his ideas upon anyone when they were the alternative to catastrop
hic waste and folly. From the summer of 1933 that saw the mid-point of his life, to its end in the summer of 1954, he had been engaged in a profound conflict between innocence and experience.

  His contemporary, Benjamin Britten, who went the other way and withheld involvement, played out this theme in public after 1945. Alan Turing left almost nothing but those pages of a short story – pages which did, however, compress acute reflections upon his life. Describing himself taking his young man to the restaurant, he portrayed the scene thus:66

  … Upstairs Alec was taking off his overcoat; underneath as always he was wearing an old sports coat and rather unpressed worsted trousers. He didn’t care to wear a suit, preferred the ‘undergraduate uniform’ which suited his mental age, and encouraged him to believe he was still an attractive youth. This arrested development also showed itself in his work. All men, who were not regarded as prospective sexual partners, were father substitutes to whom Alec had to be [illegible] showing off his intellectual powers. The ‘undergraduate uniform’ had no conscious effect on Ron. In any case his attention was now concentrated entirely on the restaurant and its happenings. Alec was enjoying himself now. Usually when he went to a restaurant he felt self-conscious, either for being alone or for not doing the right thing. …

  As it happened, this was where the surviving pages came to an end – and at an appropriate point, for lonely consciousness of self-consciousness was at the centre of his ideas. But that self-consciousness went beyond Gödelian self-reference, abstract mind turning upon its abstract self. There was in his life a mathematical serpent, biting its own tail for ever, but there was another one that had bid him eat from the tree of knowledge. Hilbert once said that Cantor’s theory of the infinite had created ‘a paradise’, from which mathematicians were not to be driven out. But Alan Turing lost that paradise, not because of what he thought but what he did. His problem lay in doing: doing or not doing the right thing.

  No one in June 1954 perceived a symbolism in the apple that he ate, an apple filled with the poison of the 1940s. Without the context, the symbol had no meaning, and could no more be interpreted than the other tiny clues he left. He might even have had the symbolism in mind before the war, when he mentioned his suicide plan to his friend James Atkins.67* For it came just at the time when he had (in an equally off-hand fashion) mentioned to his mother his unsureness about the ‘morality’ of cryptography. And while she, the Stoney, was the believer in applied science, it was James who was the pacifist – they both had a position relevant to what for Alan Turing was a crucial change in his life, that of preparedness to know sin. He might have sensed that, for him, involvement with the world meant that he would be walking into danger all the time. He might have behaved as a child – as the child of the proud, impetuous and unlucky Turings, and the child of more worldly bridge-building Stoneys – but whether consciously or unconsciously, he was a child of his time.

  His hints of self-revelation were so rare and cryptic, and showed such deep distaste for any kind of self-centred fuss, that all such questions must remain enigmatic. Another unanswerable question is that of how he finally perceived his great dream of computer intelligence, to which he had devoted the central part of his life. For although it was true, as Robin wrote, that he had given himself to ideas and things rather than to people, many of those things and ideas were the means by which he tried to approach the understanding of himself and other human beings, and to do so from first principles. That approach was one in which he had to regard social ‘interference’ as a secondary intrusion upon the individual mind. And while he had always conceded that this was a difficulty, in his last years he was taking a more active interest in other approaches to human life, in which interaction played a greater part. It was consistent with his general development that he told Don Bayley, in summer 1952, that mathematics was satisfying him less and less. Jung and Tolstoy were writers who placed the mind within a social and historical context, and there were Forster novels on his shelves when he died, novels in which the interplay of society and individual became a less machine-like play of ideas than that of Shaw, Butler and Trollope. Meanwhile social ‘interference’ in those last two years had played a peculiarly forceful part in his individual life. Could he have lost faith in the significance and relevance of his central ideas?

  Combined with the more practical kind of disappointment, regarding the incapacity of the Manchester computer (or indeed any computer of the time) to do justice to the scale of his vision, the post-war period had clearly seen an erosion of the confidence with which he emerged in 1945. On the other hand, he was not the person to give up ideas lightly, nor to allow the world to take them away from him. And neither was he the person to be disillusioned with science, by virtue of the fact that it had been turned upon himself; nor to abandon rationality because he had found himself at the receiving end of intelligence. His ruling passion for a concrete manifestation of the abstract, something that linked him with Gauss and Newton rather than with the pure mathematics of the twentieth century, inevitably took him into the application of science. Yet he showed no sign of intellectual illusions concerning the purposes of those applications. His remarks about computers had from the beginning been as ruthless as those of G.H. Hardy on mathematics. Never once had he suggested an application other than to pure research for its own sake, or to military purposes. He had never spoken of social improvement or economic welfare through science, and so had a position fortified against disillusion.

  In 1946, making a brief reference to the American atomic bomb tests, he referred to ‘the worst danger’ being an ‘anti-scientific reaction’. And however much assaulted by the application of science to ‘organotherapy’, for instance, he would not have questioned the structure of scientific knowledge itself. Indeed, he would have considered it extreme intellectual weakness to allow personal feelings to influence a view of scientific truth. He had often chided intellectuals for an ‘emotional’ rejection of the idea of intelligent machinery. It had been important for him to unshackle science from religious wishful thinking, and science for him remained independent of human purposes, judgments and feelings that were entirely irrelevant to the question of what was so. Edward Carpenter had called for a ‘Rational and Humane Science’, but in Alan Turing’s book there was no reason whatever why the rational and the humane, the data and the instructions, should be correlated. His ruthless, raw view of science was something that Lyn Newman again captured with an image of him as ‘the Alchemist’ of the seventeenth century or before – recalling a time when science was not shrouded in titles and patronage and respectability, but was nakedly dangerous. There was a Shelley in him, but there was also a Frankenstein – the proud irresponsibility of pure science, concentrated in a single person. It was indeed that terrific concentration, combined as it was with an ability to throw out all that seemed irrelevant, and with a will to think about questions that everyone would have said were hopelessly difficult and complex, that was his secret. It was this process of abstracting a simple, clear principle, and then demonstrating its truth in some concrete way, that was his strength – it was this rather than the solving of problems within a given framework. But this kind of strength did not lend itself to some of the more subtle problems that were raised by his model of ‘intelligence’.

  He had, wrote Robin, ‘a lack of reverence for everything except the truth’, and his insistence on an uncompromising materialism was motivated by that obsession for keeping truth untainted by ‘emotional’ ideas about intelligence and consciousness. But in his concern to cut away the irrelevant he had brushed aside some fundamental questions about intelligence, communication, and language, questions which arose from the embodiment of brains in a human social world. This was not, however, so much the deficiency in his thought, as a reflection upon the method of science. His model of ‘intelligence’, using chess and mathematics as its paradigm, was one which simply reflected the orthodox view of science as the repository of objective truth. In the Mind article
he had made it clear that he saw his model as one capable of absorbing all human communication, and this again reflected the positivist belief that science could elucidate human behaviour as it had already triumphed in the fields of physics and chemistry. The weak points of his argument were essentially the weaknesses of the analytical scientific method when applied to the discussion of human beings. Concepts of objective truth that worked so well for the prime numbers could not so straightforwardly be applied by scientists to other people.

  As he himself explained in introducing the central morphogenetic idea, any kind of simplification was inevitably a falsification. If this was true in a discussion of the development of cells, it was all the more apposite a comment in respect of the development of human beings, whether of their ‘intelligence’ or of their yearning for communication, experience, and love. When science used human words about human beings, could it actually separate the ‘data’ from the ‘instructions’ of society? Could it ‘observe’ or ‘experiment’, or formulate a ‘problem’, independently of social institutions? Could its assessment of importance and significance of facts, however honestly noted, do other than reflect the imperatives of the dominant ideology? In the life sciences, the borderline between the spirit of truth and the esprit de corps was not as clear as it might seem in physics and chemistry. And this difficulty, that of separating fact from act, was very close to the weakness of his arguments for machine ‘intelligence’.

  This was a super-Gödelian problem, concerning the capacity of scientific language to jump outside the society in which it was embodied, and a problem to which Alan Turing’s mind was not attuned. Nor indeed, was the scientific mind of his time. Those who in the 1930s and 1940s wished to draw connections between social structures and scientific knowledge tended to be those determined to graft social systems onto science, or to derive them from science. Most notably the Nazi and Soviet ideologues were doing this, but Polanyi too, in opposing the influence of the mechanical marxism of the 1930s, was nudging science into a sophisticated revival of Christianity. He too was trying to push science around, wanting it to come up with answers that would fit in with a pre-existing religious and political philosophy. Such a thing was quite foreign to Alan Turing, who believed that he was keeping himself securely within the realm of experimental truth.