The Essential Turing

"The quintessential Turing for philosophy is certainly the Turing test as described in The Imitation Game . The Turing test has in it a Kantian lesson. Sadly, if you look at the Loebner prize, they have a medal that has ‘Can a Machine Think?’ on it. Unfortunately they missed Turing’s answer to that question, which is that it is “too meaningless to deserve discussion.” He didn’t ask that question in the paper. What he did say is that because this question doesn’t provide the conditions of possibility for an answer – because we don’t know what ‘think’ is, and we don’t even know what a ‘machine’ is – we can’t answer it. But we can run a test and if you can’t see a difference between the answers of a human and a machine, then the machine has passed the test. So what Turing tells us is that you need to be clear about the level of abstraction at which your discussion is taking place. Unfortunately ‘level of abstraction’ has a technical sense in computer science which is often misunderstood in philosophy because there are no levels – levels of abstraction don’t come in a hierarchy. If you look at a house, you can look at it from the perspective of the owners, the council, economic, a lawyer’s perspective – these are all different levels of abstraction. In the Turing test, the level of abstraction is provided by the questioning game and the comparison of the two players at the level of their abilities to understand questions and answer them meaningfully. There’s something of Charles Sanders Peirce in this, you’re right. He’s another of my heroes, another figure in the history of the philosophy of information, and if I’d had six book choices I’d have included him. Sometimes you really have to stop looking for the essence of the ingredients but look at the effects that the ingredients have."