Marvin Minsky: The idea is that the mind is a highly evolved, very complicated mechanism with — and it very rarely has just one way of doing things. And that’s where it seemed to me psychological science got stuck. People would say, “Well, does learning work this way or that way? Or is memory organized this way or that way?” And it seemed to me that clearly people, if they used any particular way, no matter how good, it would get stuck on some kinds of problems, and you’d have to switch.

So what we were doing in making the “Society of Mind” theory is saying there’s got to be a command and control hierarchy — or not hierarchy, there’s got to be a lot of different ways this thing could work, and different parts of it have to know when they’re doing badly or they have to have critics. And, actually, I’m finishing a new book about how the mind works, and this book is called The Emotion Machine, and I think it’s going to explain to everyone just what emotions are. And it turns out they’re very simple and very complex. An emotional state is just a particular way of thinking. If you’re angry, you think in a certain way. It’s not that there’s thinking and emotions which flavor it. It’s that there are different kinds of thinking.

So if a person’s angry, it means that there’s some problems bothering him, a situation that he’s got to do something about, or she, and you have to do something pretty quickly. You’re going to turn off all your wonderful resources for figuring out what’s best in the far future. Maybe you’ll turn off most of your mechanisms for doing comfortable, smooth, graceful social relationships. And if this guy’s annoying you enough, maybe you’ll just hit him or insult him or do something that people would say is very emotional.

But from the point of view of the parts of your mind that are still working to solve this problem, these are just the right things to do if you’re in a hurry. So most emotional behavior has evolved. These different subsets of how the mind — your mind will work — have evolved to be quite good at handling particular situations. And so people say, “Well, what is emotion? It’s so mysterious.” The answer is, “No, it’s so trivial.” We just give these emotional names to the different ways people have of thinking.