It’s odd to consider that the gadget you’re reading this on started out as a tape thought experiment. Not silicon. not circuits. Just a hypothetical, endlessly long strip with a head that could move along it and read symbols. Alan Turing drew that image in 1936, and the computer was waiting somewhere in that drawing.
He was not attempting to construct a machine. He was attempting to resolve a dispute. The Entscheidungsproblem, a German term that even native speakers often mispronounce, was a problem for mathematicians at the time. The underlying question was fairly straightforward: could you create a methodical process that would determine the truth or falsity of any mathematical statement? Yes, Hilbert thought. After giving it a lot of thought, Turing decided against it, and he demonstrated this by creating an imaginary machine.
| Full Name | Alan Mathison Turing |
| Born | 23 June 1912, Maida Vale, London |
| Died | 7 June 1954, Wilmslow, Cheshire |
| Education | King’s College, Cambridge; PhD at Princeton University under Alonzo Church |
| Known For | The Turing machine, the Turing test, breaking the Enigma cipher |
| Wartime Role | Codebreaker at Bletchley Park, working on the German Enigma |
| Famous Paper | “On Computable Numbers” (1936); “Computing Machinery and Intelligence” (1950) |
| Honours | Posthumously pardoned in 2013; face of the Bank of England’s £50 note (2021) |
| Field | Mathematics, logic, cryptanalysis, early computer science, mathematical biology |
| Lasting Influence | Foundational thinker behind modern computing and artificial intelligence |
That move has a subtle audacity to it. He constructed it on paper because he needed something tangible to argue against. The states, the rules, the symbols, and the tape. The machine can read a cell, move left or right, stop or not stop, and follow instructions. That’s all. Nevertheless, the architecture of all subsequent laptops, servers, and smartphones can be found buried within that simple model. In a slightly unsettling way, it’s difficult not to find that beautiful.
Due in part to the movie, the majority of people are familiar with the wartime narrative. The Enigma machine, Bletchley Park, and the cryptological “bombes” that clattered in wooden huts. Despite the seemingly absurd numbers—roughly 159 billion billion possible configurations—a small group of engineers and mathematicians managed to find a solution. Some historians contend that it was the reason the war ended years earlier. Some are more circumspect. In any case, Turing was at the center of the massive repercussions.
What came next is frequently overlooked. He posed a question in 1950 that remains largely unanswered: are machines capable of thinking? He circumvented the philosophy by suggesting a test called the imitation game, in which a person attempts to distinguish between a machine and a human using only text. That question seems less scholarly now than it did seventy-five years ago. Everybody who has spent an evening conversing with a contemporary AI has experienced at least one brief moment of mild confusion, the slight shock of wondering what or who is on the other end.
It is more difficult to write about his demise. He was forced to choose between hormonal treatment and prison after being found guilty of homosexuality in 1952. He opted for the latter. Two years later, he passed away from cyanide poisoning, which was determined to be a suicide. The £50 note was issued in 2021, and the pardon in 2013. Depending on the day, both gestures feel either inadequate or touching.
Observing all of this from a distance gives the impression that Turing’s work quietly assembled the future rather than predicting it. The bombs, the test, the tape, and the incomplete paper on biological patterns all pointed in a direction that would take decades for the rest of us to catch up. Maybe we haven’t yet.
