The Imitation Game, the biopic about the life of Alan Turing, just won the Oscar for best adapted screenplay. While I enjoyed the film, and I’d recommend it, I agree with NPR’s Linda Holmes’ wry assessment that The Imitation Game was ‘a film that was “adapted” from a book about Alan Turing, and quite liberally adapted from reality.’
While the story of the film is a moving one (you could not help but be moved by screenwriter Graham Moore’s acceptance speech), I am saddened that so much good material was left on the table. If this was our big chance to share Turing’s amazing accomplishments with the world, a lot more could have been said, and some things could have been said better. Christian Caryl, writes that the film was A Poor Imitation of Alan Turing, while Alex von Tunzelmann goes so far as to suggest slander. A visually presented fact-checking by the Washington Post’s Stephanie Merry similarly finds as much fiction as fact.
Copeland’s short book is gripping and informative. And it is technically accurate while still being accessible. I could barely put the book down once I started reading it.
Stored program computers
Perhaps the biggest miss by the movie is a central theme of Copeland’s book, which is Turing’s invention of the stored-program computer, i.e., software. The computer that Turing’s code-breaking unit built during the war was a purpose-built computer, but laid the groundwork for methods later used to implement a general-purpose, stored program computer. Despite knowing about Turing’s machines, I failed to appreciate that software, embodied in Turing’s universal machine, was a grand insight. I have tended to focus too much on Turing’s universal machine’s connection to computability, leading me to be frustrated that Church‘s elegant lambda calculus has been given short shrift. While more people should learn lambda calculus in their theory of computing classes, I now have a better appreciation that Turing’s vision of software (which is not so clear in lambda calculus) was indeed revolutionary. I have Copeland’s clear, thematic prose to thank for this.
As ably stated in the critiques cited above, the film portrays the efforts at Bletchley at the start as frustrating and futile. But, in fact, the insights portrayed in the film as the ones leading to breaking Enigma were the easy ones, which they’d gotten right away (such as exploiting the repetitious weather reports as a kind of chosen ciphertext). As Copeland ably describes, more advanced insights followed the early ones, allowing them to crack the toughest problems. And some help came from the derring do of others, such as the capture of Enigma materials from German ships. Even a certain Lieutenant Ian Fleming makes an appearance in the book, proposing a James Bond-like scheme that nearly happened. Gripping stuff!
The film quickly passes over what happens after the war, which is the race to build a true stored program computer. Copeland’s book covers this phase, its players, and its ups and downs. The book also discusses Turing’s other contributions during this period, including the famous Turing Test, proposed in a 1950 paper. Because “thinking” is hard to define, said the paper, a more practical test of whether a computer can think is whether it can imitate a real human being. This test is what the what the film’s title, “The Imitation Game,” refers to, but sadly the film itself does not explore. Recently, a computer appears to have passed the test. (Now we have to get it to talk to itself, as amusingly done by two chatbots.) Turing’s many other contributions revealed in the book I was hardly aware of, including “artificial life,” electronic music, and even sequential analysis (from statistics). Oh, and did I mention he was an Olympics-caliber runner?
The book also presents a more studied read of the evidence concerning Turing’s untimely death after his conviction for gross indecency. This studied read contrasts the film’s exaggerated one. To believe the film, it is as if the hormonal treatments (as supposed “therapy”) that Turing underwent completely sapped him of his intellect and verve, and drove him to commit suicide. But in fact he was off these barbarous treatments for a full year before he died, and was actively engaged in new work. Those who knew him, according to Copeland, disputed that he showed any signs he might kill himself. At the least, Copeland’s discussion of the circumstances casts doubt on any certain pronouncement of suicide. The film errs in the other direction, painting a picture that even more strongly suggests suicide than do the facts. This is a shame because it encourages casual observers to more quickly caricature Turing as merely a tragic character and fail to take note of his amazing accomplishments. These accomplishments form the underpinnings of the “Information Age” we are now fully a part of.
Reality is just as entertaining, and more inspiring, than the fiction, as entertaining and inspiring as the fiction may be. For those interested in learning more about Alan Turing’s amazing contributions to humanity in general and computer science in particular, check out Jack Copeland’s excellent book, Turing: Pioneer of the Information Age.