I did "The Intelligent Eye", which was based on my Royal Institution Christmas lectures. These are lectures that go back to Faraday every year in the Royal Institution and in the last few years they’ve been on television, six of them. I think it’s fewer now but it was six when I did it and George Porter was the director at the Royal Institute at that time, whom I liked enormously. I had great fun doing all that and the lectures were called "The Intelligent Eye". I had lots of experiments but the problem was that I was planning these lectures, a lot of work doing these lectures actually, just when I had moved to Edinburgh from Bristol so I didn’t have a laboratory because we didn’t have our laboratory in Edinburgh because it was supposed to be this church which was taken away from us before the last moment, if you see what I mean, and being sort of 400 miles away from where one’s supposed to be was very bad actually for getting going in Edinburgh in a new department. At any rate, we did, in the end, do it and I think the lectures worked, I thought, rather well and it resulted in the book "The Intelligent Eye", which I’ve always rather liked. It emphasised the importance of rules in the perception and again I had a whole load of illusions when the rules were not appropriate although the physiology is working all right, it’s misdirected, and then you generate systematic illusions. Then by looking at the illusions and measuring them you can deduce what the brain was trying to do, in other words you can work backwards and discover its strategies from the errors, you see, by the mismatch between what it’s doing from past experience to the present situation. You can infer the cognition or the rules or the strategy or the assumptions that the brain is working from. I rather like that, so that illusions become key phenomena for investigating mind and brain. Errors are very, very crucial so there are practical interests like in flying or driving really matters, you see the thing right or reasonably right, you know, but when you get a systematic error it’s immediately evident but what’s going on in there although the physiology is working perfectly okay. I’ve always found that an extremely exciting idea and it’s really the central idea, I think, in both those two books, "The Intelligent Eye" and "Eye and Brain" really. I still believe in that. And since then you’ve done loads more books. Yeah. Partly successful. I did "Mind in Science" which, in a way, I think inspired Brian not nearly as good as, Bertrand Russell’s book, "Human Knowledge: it's Scope and Limits". It’s an ambitious book in that it’s got the philosophy of knowledge gaining, epistemology, it’s got the history of psychology back to the Greeks with quite a bit of physiology, so it’s really a sort of history book back to the Greeks plus a sort of philosophy book about what’s really going on in physiology and psychology so it’s got an overview with a historical basis. I enjoyed writing it but it’s never really taken off. It’s only been printed once, not in print now. I can’t honestly write it up as one of my successes. It wasn’t a total success but I learned a lot writing it.