The Language of Thought

"The Language of Thought is a really famous book in the philosophy of mind and it’s really important for linguistics as well. Fodor was a brilliant writer. He died a couple years ago. He writes really difficult stuff, but it’s actually funny. (Though this is not his funniest book, by any means—I think he was just getting started.) This book does many things, but the reason I chose it is that it’s the first articulation of an idea he then took further and further in his career: that you can be very creative not only with language, but also with thought. That’s been very interesting for my own research. Language is very systematic. If I say to you the sentence, ‘Anson bit Lilly’, you know what that means. And if I say ‘Lilly bit Anson’, you know what that means. The bits you’ve got come together to create certain meanings in a systematic way. If A did something to B, then it could be the case that B did something to A. There’s a system to it. What Fodor does in that book is argue that thought is productive. It’s got this creative capacity. You can think all sorts of crazy thoughts you’ve never had before and it’s highly systematic. So thought must work like language works. At the time it was written, Chomsky had recently been saying, ‘The way that language works is that you’ve got basic bits of language and then you’ve got a general set of rules that combine them to create larger bits of language in a systematic way. That’s what gives us this free capacity to build sentences in a way where we understand the meaning of new sentences that people say to us and we can create new sentences as we need them.’ “Apes are really good at some things and we’re really good at other things. We’re really good at language and apes are not” That was Chomsky’s idea for language and what Fodor said is, ‘Thought has the same properties’. That means that basically our minds are working along the same lines as Chomsky said language works. At the heart of human psychology is what Chomsky calls—and Fodor calls as well—something like a computational machine. It takes things and puts them together and creates new things out of it. That’s what gives us this ability to be systematic and productive. For Fodor and Chomsky, all this emerges from the work done on the theory of computation by mathematicians like Turing in the 1930s. Even though he was working on other stuff, Turing had one of the best ideas in psychology, which is that you can treat aspects of the human mind like a computer. We can explain that systematicness and productivity of thought by appealing to what Turing did when he figured out how to make computers work. I’ve overly simplified this, but that’s the basic idea. There are lots of other things in the book that philosophers will be struck by more than I will, but as a linguist that’s what struck me: the notion that this approach to computation is fundamental not just to language but to our general psychology as well. No and yes. This is an area where there is quite a lot of controversy, similar to what there might be in linguistics. You can make a computer look like what you think a brain looks like, with computational neurons in it. And they all just connect to each other and then what you do is you feed information into this collection of neurons and you tell them what you want out of it. And they just shoogle—‘shoogle’ is a Scottish word meaning to shake around—until they match the input with what you want the output to be. That idea underpins most AIs these days. So if you have Siri or Alexa—which can do these incredible things—the way you get speech synthesis to work is that they have these artificial neurons and you play them ‘the dog jumped over the fox’ and they then shoogle their neurons around until they get aligned to give you the right results. Again, it’s more complex than that, but that’s the basic idea. Support Five Books Five Books interviews are expensive to produce. If you're enjoying this interview, please support us by donating a small amount . That’s very different from the computational view that Fodor was pushing in this book. That view says that you get to the dog jumped over the fox by saying ‘the’ and ‘dog’ and ‘jump’ and ‘over’ and ‘the’ and ‘fox’ and you’ve got ‘the’ twice and it’s combined with dog once and fox once. It’s the systematic building up of meaning through rules. So those are two different ways that people think about the mind. There’s Fodor’s way, which is called the computational theory of mind, and then there is this other way, which is the neural network theory of mind. That’s still a big fight. It’s one brand of linguistics; it’s definitely my brand. But there are masses of other really interesting areas in linguistics, which are not like that. Over the last 10-15 years, I’ve been working quite a lot with sociolinguists who are interested in how language is used socially, how language changes, how your identity is expressed by the kind of language you choose to use. You collect all the data and you do statistics on the data, but it’s a very different kind of science . That’s also philosophical in that you’re thinking about issues of identity, of class and gender and sexuality, but it’s different from the questions of cognition and meaning that I’ve been talking about. These are two quite distinct areas of linguistics and you can do either of them. Not that many people do both. That actually goes back to one of your earlier questions, about whether there is a bit of a fight going on in linguistics. Certainly these two areas of linguistics pulled apart in the 1970s, and didn’t talk to each other through the 80s and 90s. But they have now started to talk to each other again, over the last 20 years. There have been a number of people involved in trying to make this work. I ended up sharing a flat with a sociolinguist when I was a lecturer in York. We used to have arguments about stuff but we ended up working together. So I’ve ended up being a weird crossover between the Chomskyan linguistics stuff that is my heartland and the sociolinguistic stuff, which is very different kind of set of ideas, that I also find totally fascinating. I write about them in the last chapter of my book."