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Are we ready for computers that know how we feel?

More on Digital Culture in Atlantic Unbound.

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A Conversation with Daniel Dennett

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  Daniel Dennett
Harvey Blume: It seems computers help realize one of the goals of analytic philosophy -- namely, to produce unambiguous statements. After all, you can't get rid of ambiguity in natural language but you can -- and you have to -- in the algorithms of computer code.

Daniel Dennett: Computers keep you honest in a way that philosophers have been hankering after for a long time. There's no place for hand waving. There's no place for impressionism in creating a computer model or an algorithm. At the same time, there's plenty of room for hand waving when it comes to interpreting that model. Computers force you to get clear about things that it's important to get clear about. AI is really a new and better way of doing certain sorts of philosophy.

HB: When did you begin to see cybernetic processes as similar to the processes of evolution?

DD: Right at the outset. Right at the center of my dissertation I argued that learning had to be evolution in the brain, and there had to be learning algorithms in the brain.

What happened was that over the years I kept underestimating the amount of hostility there was to evolution. I wanted to say: This is obvious. This is like gravity, folks -- what's going on? Reading Richard Dawkins greatly deepened my understanding of evolution, and excited me. It was when I read The Selfish Gene that I became more than casually interested in what was going on in evolutionary biology.

HB: Has Cog the robot lived up to your expectations?

DD: Cog hasn't come through in the last four years the way I'd hoped. It's also true that Cog has not been the primary work of more than three graduate students. Rod [Brook] hasn't been able to devote even a quarter of his time. I haven't been able to devote even 10 percent of my time. Other things have intervened.

Herb Simon once predicted that a computer would beat the human chess champion in a decade. [Marvin] Minsky did too -- a lot of them put their money on it. They were wrong. They were wrong not by an order of magnitude but by a factor of three or four. It didn't take ten years; it took more like thirty years. But that's not bad. The fact is that research went in other directions. Things bogged down, and it took a while. Similarly, Cog is not on its schedule. We're still in the first wave of features. But we're making steady progress on those. I don't think any abyss has opened up in front of us.

HB: Analytic philosophy has always been influenced by science. That seems to be true of your thought as well.

DD: Analytic philosophy certainly aspires to the sorts of objectivity and opportunities for confirmation and refutation that science does. One of the things analytic philosophy always held against various continental schools was that they seemed to be doing something more like verbal ballet.

My view of science is very much an enlightenment view. Aside from minor disagreements, it's pretty close to [E. O.] Wilson's view in Consilience. That's not an accident. We've spent a lot of time talking about it. Much of what is said about science as an objective, progressive, best-ever technology for getting at the truth I simply think is right, and I believe people who think otherwise are deeply mistaken.

From the Unbound archives:

Books & Authors: All for One, One for All (March 18, 1998)
Can science call the postmodernist bluff? An interview with Edward O. Wilson, the author of Consilience: The Unity of Knowledge, who says it can -- and must.
I also think the way progress is made in science is greatly abetted by the temporary hampering of the imagination. Schools of scientific thought constrain themselves in ways that, in retrospect, turn out to have been wrong. But that very constraint helped inspire and provoke the imagination.

HB: Can you expand on the role of the algorithm in your thought? It seems to be a unifying idea.

DD: It's one of them. Let me get at it this way: David Hume wrote about complex ideas and impressions. What he really wanted to do was explain what he called the association of ideas -- how one idea brings the next idea along in its train. He wanted to explain the marching order of ideas without having to postulate a director to direct the show. I was trying to explain this and a student said, "Hume's got to get the ideas to think for themselves" -- to which I said, "to think themselves." You've got to get the thinker out of there. If you've still got the thinker in there, you haven't begun working on the mind.

How do you break that regress? Hume tried. Locke tried. Skinner tried. Turing succeeded. It was Turing who figured out how you could get ideas to think themselves. You write down a recipe for how to do some thinking, and give it to a mathematician. He follows the recipe, does the thinking. Turing says, Yeah, but you can leave the mathematician out of it. You can just give the recipe to the machine and eliminate the middleman.

Eliminate the middleman. And the thinking just happens.

Turing shows that if a computer can add, subtract, multiply, and divide, and if it can tell the difference between zero and one, it can do anything. You can take that set of mindless abilities and build them up into structures of indefinite discriminative power, indefinite discerning power, indefinite reflective power. You can make a whole mind; you can solve Hume's problem; you can get ideas to think for themselves on this slender base. That's the idea of an algorithm.

And what would Darwin say? What does it mean to have an evolutionary algorithm? We look out and see all this beauty, all this fabulous design, all this R&D. Darwin showed how all that research and development can be performed by an ultimately mindless, motiveless, mechanical, if not necessarily malignant, process.

HB: I infer from your work that the job of philosophy is to show how various disciplines are similar to one another in a way that people working within those disciplines might not be able to see as clearly. Is that the role of philosophy?

DD: That's one of the roles. Life is short, and life is complicated. People can't do everything they'd like to do. And one of the things people can't do is keep track of how their particular bailiwick, their somewhat blinkered specialization, fits into the larger picture. There are always problems at the interface: How does this fit with that? One of the goals for philosophers is to do this better than other people. It's not the only role, but it's one I take very seriously.

HB: Can you name another role?

DD: In the beginning, it was all philosophy. Aristotle, whether he was doing astronomy, physiology, psychology, physics, chemistry, or mathematics -- it was all the same. It was philosophy. Over the centuries there's been a refinement process: in area after area questions that were initially murky and problematic became clearer. And as soon as that happens, those questions drop out of philosophy and become science. Mathematics, astronomy, physics, chemistry -- they all started out in philosophy, and when they got clear they were kicked out of the nest.

Philosophy is the mother. These are the offspring. We don't have to go back a long way to see traces of this. The eighteenth century is quite early enough to find the distinction between philosophy and physics not being taken very seriously. Psychology is one of the more recent births from philosophy, and we only have to go back to the late nineteenth century to see that.

My sense is that the trajectory of philosophy is to work on very fundamental questions that haven't yet been turned into scientific questions. Once you get really clear about what the questions are, and what would count as an answer, that's science. Philosophy no longer has a role to play. That's why it looks like there's just no progress. The progress leaves the field. If you want to ask if there has been progress in philosophy, I'd say, look around you. We have departments of biology and physics. That's where the progress is. We should be very proud that our discipline has spawned all these others.

HB: Your starting point is analytic philosophy, but you end up with a grand synthesis, don't you?

DD: It's a grand synthesis, but one that has a sort of minimalist starting point. The minimalist starting point is recognizing that you don't have to start with Descartes' division, you don't have to start with a Cogito. You don't have to start with a dichotomy between subjective and objective, between the first-person point of view and the third-person point of view.

Descartes says there's the rule of mind and the rule of matter. This polarity, this division, has many manifestations. In the continental tradition they talk about Geisteswissenschaft and Naturwissenschaft, sciences of the mind and the rest of the sciences. Everywhere you look you see people who like this division. They say there's nothing that biology or physics or chemistry can teach us about literature, ethics, religion, or even psychology. And then there are those who say you can get all of this under one rubric. There have always been people who wanted to be good materialists.

The only thing that's novel about my way of doing it is that I'm showing how the very things the other side holds dear -- minds, selves, intentions -- have an unproblematic but not reduced place in the material world. If you can begin to see what, to take a deliberately extreme example, your thermostat and your mind have in common, and that there's a perspective from which they seem to be instances of an intentional system, then you can see that the whole process of natural selection is also an intentional system.

It turns out to be no accident that biologists find it so appealing to talk about what Mother Nature has in mind. Everybody in AI, everybody in software, talks that way. "The trouble with this operating system is it doesn't realize this, or it thinks it has an extra disk drive." That way of talking is ubiquitous, unselfconscious -- and useful. If the thought police came along and tried to force computer scientists and biologists not to use that language, because it was too fanciful, they would run into fierce resistance.

What I do is just say, Well, let's take that way of talking seriously. Then what happens is that instead of having a Cartesian position that puts minds up there with the spirits and gods, you bring the mind right back into the world. It's a way of looking at certain material things. It has a great unifying effect.

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