Transcript for Andrew Hodges on Alan Turing

Jim Fleming: Where does creative genius come from? How did a shy, awkward British schoolboy permanently alter the world through the application of mathematical logic, algorithms and codes? The best, and most definitive, portrait of Alan Turing's intellectual development is Andrew Hodges' famous biography "Alan Turing: The Enigma." Hodges traces the origins of some of Turing's most creative insights to the most important friendship of his life: with a boy he met at school.

Andrew Hodges: Well, there's a very interesting story there about the whole nature of where originality and real scientific impetus comes from. There certainly was something very special that happened while he was at school, but then propelled him into undergraduate study. Yeah, the person who really brought him out of isolation and made him someone who was actually communicating and thinking of discussion and a collaborative life in science was this other boy called Christopher Morcombe. There are several things mixed together here, I mean he was obviously also a very bright boy, full of interest in science and fundamentals in the same way. But also it was at this time that Alan Turing must have been becoming aware of his identity as a gay man because his feelings for this other boy were obviously something quite out of the ordinary. And I think he was - must have been becoming strongly aware of that. And what made the story very dramatic is that Christopher Morcombe suddenly died in 1930 and the combination of intellectual loss but great emotional and romantic loss must have been absolutely - very very traumatic for Alan Turing. He was only 18.

Fleming: But I did have the feeling from the way you wrote about it that in some way Turing's pursuit of intellectual accomplishment was to some degree a desire to do what he thought Morcombe would have been able to do had he lived.

Hodges: Well he did actually say something like that. Of course you can say something like that when you're 19 and really not mean very much a little bit later. He wrote a little essay for Christopher Morcombe's mother. And it's an essay about the problem of - well, of scientific determinism. It's the classical problem of how you can have free will and minds and consciousness in a world which seems to be just governed by physical law. That's an old, old problem. It's clear - absolutely clear from what he's saying - that he's thinking about the departure of Christopher's mind - how it is that a mind could exist in this physical sense and then disappear and then be at an end. What on earth happens? And he finds some reconciliation in the quantum mechanical picture. Of course, that's an extraordinary thing to do - not many people try and reconcile their deep emotional feelings by thinking about modern theories in science. But it shows the whole grounding of his thought - caring so deeply about the puzzle of what the mind is, how it's related to the physical world, how we can describe it in a scientific way. Now that's - those are the things which he pushed forward in the rest of his scientific career.

Fleming: He lived in an extraordinary time, I guess you'd have to say. He lived in the 1930s just at the world was breaking into war. And one of the things that he is best remembered for is the work that he did for the British secret service for code breaking - figuring out the way to solve the Enigma coding that the Germans were using.

Hodges: One of the most striking things about his whole timeline, it was a period at which the most advanced and abstruse kinds of science suddenly turned out to have highly practical application. I mean, the obvious one is the atomic bomb development. But the code breaking was another example of that. And it's where he was exactly the right age and in just the right place and he realized that he could turn these really quite advanced ideas into a serious, modern, twentieth century look at the whole problem of codes and ciphers. And he also had this sort of down-to-earth, do-it-yourself mentality - actually getting involved with the engineering and machinery.

Fleming: So what did he do? What did he build in order to break the German code?

Hodges: What Turing did actually was to devise a whole - what we'd now call information theory. It's a way of measuring information. It's the beginning of really serious algorithms, I'd say. That is to say, things you would now do on a computer program. But they didn't have computers then. Computers didn't exist until they got started in the later 1940s. The funny thing about what Turing did was, he had the idea of computer program before there were any computers. And then he invented the computer as a way to make sense of the computer programs. I know that sounds a bit crazy, but that's essentially what he did.

Fleming: He saw how all of this fit together and yet he maintained in his mind the relationship between mind and machine. He was able to see that it wasn't just computing.

Hodges: That's, uh, very, very true. You see, I emphasized at the beginning, his original thoughts were about the mind. When computers got going, I mean he had to sell the idea of the computer for practical purposes. But they weren't really what he was fundamentally interested in. I mean, he just knew they could be used for all sorts of things - everything that people do now, in fact, with computers, he essentially saw the scope of it. But he said right from the beginning in 1945 that he saw it as an effort to emulate the brain and see what the brain does and experiment with what is going on in brains. So right from the start he's thinking about chess-playing programs - programs that essentially posed the question: can you call this intelligence?

Fleming: You have to wonder in all of this whether he wasn't as much trying to figure out why he was who he was - how his own mind worked - as he was in trying to emulate it mechanically?

Hodges: What's very striking is that if you read his paper published in 1950 about the artificial intelligence question - it leaps off the page, your comparison with philosophical writing. In the same journal of that period, which looks very, very dry and academic - it's full of jokes, it's full of wit, it's full of funny illustrations, all sorts of cultural references. Although he's writing about what machines could do and arguing that probably there's no limit to what machines could do. In other words he's actually putting forward in the subtext a rather strong message that he, though a mathematician, is human. And he's showing by his awareness of human life.

Fleming: It's the hundredth anniversary of Turing's birth. There have been celebrations all over the world. Has anything changed? Have there been particularly significant or meaningful reassessments of Turing?

Hodges: Uh, some things are just the same as they were in 1936. The definition of computability that Turing found - nothing's changed with that. I mean, what computers have done may be quite different from what people would have thought. They're far smaller, cheaper, there are far more of them, the do things - Facebook, whatever - no one would have thought of then. But the basic principles are just the same.

Fleming: Andrew Hodges is a mathematician at Oxford University. His biography of Alan Turing is widely regarded as one of the best scientific biographies ever written. Alan Turing's contemporaries built machines that could calculate and follow commands. Turing himself dreamed of something more: machines that could think.

(Alan Turing): I'm not mad, I don't believe that individual consciousness could be transplanted into a machine now, but given a few years who knows. But for now, I only ask: can we not house something like a human consciousness inside an inorganic vessel? Something permanent. So it will remain and learn and achieve something like wisdom - a wisdom to which you and I can refer. Something that would never die.

Fleming: Alan Turing's legacy - the Turing test - next. I'm Jim Fleming. It's "To the Best of Our Knowledge" from Wisconsin Public Radio and PRI: Public Radio International.

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