Two brainy guys discuss the brain

Head Games
Marvin Minsky's and Daniel Dennett's latest thoughts about the brain will blow your mind.
Questions by David Pescovitz/Wired


For half a century, Marvin Minsky has tried to mechanize the mind. In his new book, The Emotion Machine , the AI pioneer posits that anger, love, and other emotions are types of thought, not feeling. The idea will surely stir up controversy. But Minsky – who cofounded MIT's AI Lab and advised director Stanley Kubrick during the filming of 2001: A Space Odyssey – wants to make us think. His groundbreaking tome The Society of Mind , published in 1986, argued there's no central conductor of operations in your head, just agents working together to create awareness. In the spirit of collective consciousness, Wired challenged Minsky to a meeting of the minds with philosopher Daniel Dennett, codirector of the Center for Cognitive Studies at Tufts University and the author of several seminal brain books with heady titles like Consciousness Explained and Darwin's Dangerous Idea .

WIRED: What's wrong with the traditional approach to how the brain works?
Minsky: Physics gives us about five laws that explain almost everything. So we keep looking for those kinds of simple laws to apply to the brain. The idea in my new book is that you shouldn't be looking for a single explanation of how thinking works. Evolution has found hundreds of ways to do things, and when one of them fails, your mind switches to another. That's resourcefulness.

In The Emotion Machine , you argue that feelings result from switching on or off certain "mental resources."
Minsky: The traditional view of emotions is that they are something extra, like adding color to a black-and-white photograph. But to me, emotions are what happens when you remove other resources. Anger means you've turned off your social graces, you've turned off your cautiousness, you've turned off your long-range plans and most of your ambition, and you've turned on things that make you act more rapidly and less deeply. Recognizing this complexity adds dignity to the theory.
Dennett: Computer programmers have the luxury to create hierarchies of control. The systems, the subsystems, the sub-sub-subsystems are complete slaves. They never rebel. This gives you a model of the mind with the highest echelons of logic at the top. But if you think about a brain as a community of individually semiautonomous, even independently evolved agencies, as Marvin has, you realize that the agencies have to be browbeaten and they have to form alliances. Emotions aren't an add-on but rather the politics of the whole system.

So what would a machine that worked this way look like?
Dennett: Like us.
Minsky: A well-designed program that wouldn't be so hierarchical but more like a network with resources that make requests of other resources.
Dennett: The research world is going to be impatient with Marvin because they are eager for computational models that really work. Marvin is saying, "Wait a minute, let's work out some of the high-level architectural details in a way that's still very loose, very impressionistic. It's too early to build the big model."
Minsky: Actually, I could quarrel with that. I think the architecture described in The Emotion Machine is programmable. If I could afford to get three or four first-rate systems programmers, we could do it. You can get millions of dollars to drive a car through a desert, but you can't get money to try to do something that's more human.

Why is the idea of a thinking machine so compelling?
Minsky: I think there is a worldwide survival problem. As the population grows and people live longer, there won't be anybody to do the work. So there is an urgent need to make inexpensive mechanical people that are able to do all the things that moderately unskilled people do now.
Dennett: I don't find that very convincing, Marvin. I think we're interested in it for purely curious, scientific reasons. We want to know how we work.
Minsky: Or make machines that work better than us and can solve all the problems we wanted to but couldn't. As Hans Moravec used to say, "The machines will be us."
Dennett: Marvin, I have a slogan for you that came to mind while I was reading your book. I've used it myself as a paper title. "My body has a mind of its own, so what does it need me for?"
Minsky: [Laughs .] I once peeled a label off a London bus. It read: MIND YOUR HEAD.