Alan Turing (1912-1954). The case that ends the Scientific Revolution section of Chapter 2, and the case the chapter's whole argument has to survive intact. Not because Turing's cognitive profile is harder to identify than Newton's or Cavendish's — it is not; the evidence is dense and unambiguous — but because Turing's life ended in a way that demands to be called what it was, and the species-team framing has to account for what it was without softening it.
Turing's biographical record, assembled most fully by Andrew Hodges in Alan Turing: The Enigma (1983), documents a cognitive architecture that maps onto the autism spectrum with the same clarity as Cavendish's. The social naivety was extreme and lifelong. Turing could not read indirect social signals, could not produce the small talk his colleagues expected at faculty dinners, could not understand why anyone would care about the clothes he wore or the grammar of his letters or the conversational rhythms of the common room. He wore the same battered jacket for years because the jacket worked. He rode his bicycle with a gas mask to avoid hay fever because the gas mask worked. He chained his coffee mug to the radiator in the King's College common room because someone had moved his mug once and that kind of disruption was intolerable, and the chain solved the problem, and the chain remained in place for years afterward while his colleagues learned to navigate the fact that the coffee was where the coffee lived and nobody was allowed to touch the coffee. The intense restricted interests are documented from childhood — chemistry, mathematics, logic, computation, and later morphogenesis (the mathematical theory of biological form) pursued at a depth that none of his teachers or colleagues could follow without effort. The literal-mindedness extended to his personal life in ways that would eventually prove catastrophic. The monotropic focus was such that Hodges describes Turing's wartime colleagues finding him, during the intensity of the Enigma work, having apparently forgotten to eat or sleep for periods that struck even the hardened cryptanalysts of Bletchley Park as unusual.
In 1936, at the age of twenty-four, Turing published On Computable Numbers, with an Application to the Entscheidungsproblem. The paper answered a question David Hilbert had posed about the decidability of mathematical problems, and answered it by inventing a hypothetical machine — what Turing called an "a-machine," and what the rest of the world would later call a Turing machine — that could read, write, and transform symbols on an infinite tape according to a finite set of rules. The hypothetical machine was a theoretical device. Turing had no intention of building it. The machine existed to prove a point about what was and was not computable in principle. But the point Turing proved was that a single machine, given the right rules and the right input, could perform any computation that could be performed at all. One machine. All computations. The universal Turing machine was the theoretical foundation of every computer that has ever existed, and Turing invented it nine years before anyone built a computer. The 1936 paper is the clearest single case in the history of science of the discovery specialty producing the foundational abstraction of a civilizational transition before the transition was visible to the rest of the civilization.
Bletchley Park is where Turing's cognitive architecture was, briefly, given an environment that actually rewarded what it could do. The Government Code and Cypher School had been given the impossible task of breaking the German Enigma cipher, and the people assembling the Bletchley team had done something that was at the time unusual and would become less unusual as the century progressed — they had recruited for cognitive specialty rather than for social fit. Chess champions. Classical scholars. Crossword prodigies. Mathematicians. Linguists. The Bletchley team included a significantly higher proportion of cognitive specialists with recognizable ND profiles than any other institution in Britain at the time, because the mission was impossible and the team had been forced to abandon the credentialing criteria that would have filtered out the specialists who could do the work. Turing arrived in September 1939. Within months he had designed the Bombe, an electromechanical device that automated the search for Enigma settings, and within two years his team was reading the bulk of German naval communications. The best historical estimates suggest that the Bletchley work shortened the war by at least two years and saved millions of lives. The Bletchley integration was real, and it was the closest thing to a functional species-team environment that Turing ever worked inside. The integration specialists at Bletchley — Gordon Welchman, Hugh Alexander, Max Newman, Stuart Milner-Barry, and others — worked alongside Turing's specialty and translated what Turing was doing into actionable intelligence products for the Admiralty and the Air Ministry. Welchman in particular made crucial improvements to the Bombe that Turing himself recognized as essential.
But the integration at Bletchley happened under the Official Secrets Act. Nothing about it could be publicly known. Nothing about it could be credited. The integration work that would normally have turned Turing's wartime discoveries into postwar academic standing, into institutional influence, into the normal currency of scientific reputation — that integration work was classified. Turing finished the war with the knowledge that he had probably done more than any other individual to break the German communications system, and with the simultaneous knowledge that none of it could be mentioned. He went back to academic mathematics and early computer engineering with his hands officially empty. The Bletchley record would not be declassified until long after his death.
The postwar period is where the integration partner becomes something worse than classified. It becomes hostile. Turing moved to the National Physical Laboratory and designed the Automatic Computing Engine (ACE), one of the earliest detailed designs for a stored-program computer. The design was too ambitious for the NPL's engineering capacity and the project stalled. He moved to Manchester and worked on the Manchester Mark 1, one of the first operational stored-program computers in the world. He wrote Computing Machinery and Intelligence (1950), the paper in which he proposed what is now called the Turing test as the operational criterion for machine intelligence. He began what would become his final major work, the mathematical theory of morphogenesis, which applied reaction-diffusion equations to the problem of how biological form develops from undifferentiated tissue. The morphogenesis paper (1952) is still cited in developmental biology.
In January 1952, Turing reported a burglary at his home in Manchester. He had been in a casual sexual relationship with a young man named Arnold Murray, and an acquaintance of Murray's had broken into the house and stolen a small amount of money and some of Turing's possessions. Turing went to the police to report the burglary. In the course of reporting, and with the literal-mindedness that Hodges' biography documents as one of Turing's most consistent traits across his life, Turing described the nature of his relationship with Murray. Homosexual acts between men were a criminal offense in Britain under the Criminal Law Amendment Act of 1885. The police, who had come to investigate a burglary, instead arrested Turing for the greater crime of being the victim of one. He was convicted of "gross indecency" in March 1952. The court offered him a choice: prison or "organo-therapic treatment" — chemical castration, via injections of synthetic estrogen intended to suppress libido. Turing chose the injections because prison would have ended his academic work. The injections continued for a year. They produced the physiological effects the court had intended and the additional effect of gynecomastia, which Turing tolerated with the same literal-mindedness with which he had reported the burglary. His security clearance was revoked. The government that had used his cognitive specialty to shorten the war by two years had decided, with the same institutional apparatus, that the specialty was now a threat to national security because its carrier was also a convicted homosexual and therefore presumptively vulnerable to Soviet blackmail.
In June 1954, Alan Turing was found dead at his home in Wilmslow. The inquest determined he had died of cyanide poisoning, and a partially eaten apple was found beside the bed. The coroner ruled it suicide. He was forty-one. The reclamation happened later, in stages: Hodges' biography in 1983, gradual declassification of the Bletchley material, the Turing Award (the highest honor in computer science) established in 1966, the formal apology issued by Prime Minister Gordon Brown in 2009, the Royal Pardon in 2013, the £50 note bearing Turing's face in 2021. None of it brought him back.