You have this paradox in biology that, although there may be underlying principles, the actual results are often very, very gadgety. I mean it’s like- it's like an automobile, the basic idea of the internal combustion engine is relatively simple. But if you look at a modern car with all the gadgets for adjusting when the spark comes, for example, with electronic things raising and lowering the windows and all the other things that you have in your car, you see how- what- how much elaboration comes from a quite simple principle of internal combustion. But in that case we know roughly what everything does because it was designed by us. So we know that the muffler reduces the sound, for example, and if you suddenly found your car’s making a very loud noise it’s probably because the muffler’s gone and so on. Well, we have crude knowledge like that but remember in the case of our brains and our bodies, we didn’t design them. They're evolved, and therefore we have to look at it as something that somebody else designed, what’s sometimes called reverse engineering. It happens in the- in the commercial world when one firm produces a gadget and another firm buys it and tries to take it to pieces and find how it works, that’s called reverse engineering. But, in our case, it’s reverse engineering what you might call a foreign culture as we don’t understand the set of ideas which, as it were- there weren’t even any ideas which produced the brain, we don’t understand the principles which produced the brain although we’re groping towards them. So you can see it’s a very complicated and difficult problem. And some people, I mean, I don’t say you, but some people that aren’t scientists might still be tempted to, you know, give up on that and go for the argument from design, although the idea, they believe that-Well yes, of course, but I don’t think you’ll ever, ever satisfy such people until you can give very convincing and detailed explanations which at the moment often we have to do a certain amount of hand waving. We can say we can’t see in principle why it hasn’t been done by- by evolution, by natural selection, but obviously the more cases we have worked out in detail the more we can counter any argument which says 'oh but it couldn’t have happened that way because'. That’s why you need detailed scientific knowledge as well as the principles because you need the detailed knowledge to refute counter arguments.