3. Can artificial intelligence have human-style common sense?

There are several large-scale projects exploring that issue. There’s the one that Douglas Lenat in Texas has been pursuing since 1984. He has a couple of million items of commonsense knowledge, such as “People live in houses” or “When it rains, you get wet,” which are very carefully classified. But what we don’t have are the right kind of answers to questions that a 3-year-old child would be filled with. So we’re trying to collect those now. If you ask a childlike question like, “Why, when it rains, would somebody want to stay dry?” it’s confusing to a computer, because people don’t want to get wet when it rains but they do when they take a shower.

4. What is the value in creating an artificial intelligence that thinks like a 3-year-old?

The history of AI is sort of funny because the first real accomplishments were beautiful things, like a machine that could do proofs in logic or do well in a calculus course. But then we started to try to make machines that could answer questions about the simple kinds of stories that are in a first-grade reader book. There’s no machine today that can do that. So AI researchers looked primarily at problems that people called hard, like playing chess, but they didn’t get very far on problems people found easy. It’s a sort of backwards evolution. I expect with our commonsense reasoning systems we’ll start to make progress pretty soon if we can get funding for it. One problem is people are very skeptical about this kind of work.

Usually AI refers to an exploration of the utilitarian uses of the brain, like understanding speech or solving problems. Yet so much of what humans do isn’t clearly utilitarian, like watching TV, fantasizing, or joking. Why is all that behavior necessary?

Watching sports is my favorite. Pleasure, like pain, is thought of as being a sort of simple, absolute, innate,

basic thing, but as far as I can see, pleasure is a piece of machinery for turning off various parts of the brain. It’s like sleep. I suspect that pleasure is mainly used to turn off parts of the brain so you can keep fresh the memories of things you’re trying to learn. It protects the short-term memory buffers. That’s one theory of pleasure. However, it has a bug, which is, if you gain control of it, you’ll keep doing it: If you can control your pleasure center, then you can turn off your brain. That’s a very serious bug, and it causes addiction. That’s what I think the football fans are doing—and the pop music fans and the television watchers, and so forth. They’re suppressing their regular goals and doing something else. It can be a very serious bug, as we’re starting to see in the young people who play computer games until they get fat.

Many people feel that the field of AI went bust in the 1980s after failing to deliver on its early promise. Do you agree?

Well, no. What happened is that it ran out of high-level thinkers. Nowadays everyone in this field is pushing some kind of logical deduction system, genetic algorithm system, statistical inference system, or a neural network—none of which are making much progress because they’re fairly simple. When you build one, it’ll do some things and not others. We need to recognize that a neural network can’t do logical reasoning because, for example, if it calculates probabilities, it can’t understand what those numbers really mean. And we haven’t been able to get research support to build something entirely different, because government agencies want you to say exactly what you’ll do each month of your contract. It’s not like the old days when the National Science Foundation could fund people rather than proposals.