In the 1940s and 50s Lacan was of course fascinated by the new science of cybernetics and information theory, referencing Claude Shannon and Norburt Wiener among others. Turing is not mentioned, but his thinking machines are. Furthermore, Lacan contends that their binary system is also the basis of language and the structure of the unconscious. ‘The world of the symbolic is the world of the machine’ is Lacan’s mantra at this stage of his teaching and it is the analysts’ task to understand that ‘in so far as he speaks, the subject can perfectly well find his answer, his return, his secret, his mystery, in the constructed symbol which modern machines represent for us’ (II: 186). And indeed, that in the unconscious mathematics is sex: ‘while the subject doesn’t think about it, the symbols continue to mount one another, to copulate, to proliferate, to fertilize each other, to jump on each other, to tear each other apart’ (II: 185). Both Turing and Lacan, in their different ways, establish that thought is an effect of symbolization that does not necessarily require a human brain.

The missed encounter between Turing and Lacan is unfortunate because even as Lacan turned to cybernetics, Turing had already undertaken psychoanalysis in an endeavour to achieve a greater understanding of the mind. It should be noted that Turing’s analysis was entirely unrelated to his conviction for homosexuality and the sentence of ‘chemical castration’ that apparently lead to his suicide in 1954. According to Turing’s brother, psychoanalysis was an experience that he highly praised. (Hodges, 611]. Indeed, it was during his analysis with Franz Greenbaum that he wrote a curious short story concerning the events of December 1951 that lead to his conviction. In the story Turing fictionalizes himself as ‘Alec Pryce’ who has just completed a new paper on ‘interplanetary travel’ that he considers better than [the one] he’d done since his mid-twenties when he had introduced the idea which is now becoming known as ‘Price’s buoy’. Alec always felt a glow of pride when this phrase was used. The rather obvious double-entendre rather pleased him too. He always liked to parade his homosexuality … (Hodges, 564-5).
‘Pryce’s buoy’ is of course code for ‘Turing’s machine’, the pun correlating boy and machine (in this case a nautical navigational marker and transmitter of signals), but also, given that U-Boy is also a near homonym of U-Boat, condensing Arnold Murray, the boy who sunk him, on to the fatal objects he was trying to locate through breaking the ‘impossible’ Naval Enigma, an achievement for which he was decorated by the British Government.

Turing’s most famous paper, however, is the one that poses the famous ‘imitation game’ or ‘Turing test’ that accurately predicted that computers would be mistaken for human beings as they increasingly interacted. Turing prefaces this test, however, with a similar one concerning the problem of distinguishing between men and women purely at the level of symbolization, hinting that it is not just signifiers of difference that are at issue there but the jouissance that they orient. Or as his biographer suggests, sex ‘depended on facts which were not reducible to sequences of symbols’ (Hodges, 2013: 523). Similarly, Lacan’s own question concerning machines is not if they can think, but if they can be said to know, because ‘the foundation of knowledge is that the jouissance of its exercise is the same as its acquisition’ (XX: 97).

While for both Turing and Lacan ‘the world of the symbolic is the world of the machine’, since Turing’s universal computing machine coincides with its object, his followers in Silicon Valley have been encouraged in the assumption that nature itself is a Turing machine and the symbolic coterminous with the real. However, as is evident from his life and work, it is a different kind of real – the impossibility of a sexual relation – that can be located as the cause and limit of his legacy.