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Alan Alda in Scientific American Frontiers


Photo Dennett

Born in Boston, Dr. Daniel Dennett received his B.A. in Philosophy from Harvard University in 1963, and earned his Doctorate in Philosophy at Oxford University in 1965. After teaching at U.C. Irvine for six years, Dennett joined the faculty at Tufts University in 1971, where he is now a Professor of Philosophy and Director of the Center for Cognitive Studies at Tufts University

Dennett has written extensively about the mind, consciousness, and evolution. He published his first book, Content and Consciousness, in 1969 and is perhaps best known for his 1995 book, Darwin's Dangerous Idea, which explores the implications of natural selection on humanity's place in the universe. He has also published more than one hundred scholarly articles in professional journals, ranging from Behavioral and Brain Sciences to Poetics Today.

Dennett, an avid sailor, sculptor and farmer, lives with his wife north of Boston. He has two children and one grandson.


For links to this scientist's home page and other related infomation please see our resources page.

Dennett responds :

1.03.01 Jeff Dolecek asked:
What are your thoughts and feelings concerning religion in our present society? Do you believe in an all mighty being that created everything? Or do you believe religion is an idea created in our minds to delude ourselves into happiness, and as an explanation for things that cannot presently be explained?

Dennett's response:
The idea that it takes a more intelligent thing to create a less intelligent thing still seems just plain obvious to many people, probably to most people. But Darwin showed us how this "truism" can be just plain false. The process of evolution by natural selection is not itself intelligent, or purposeful, but it generates intelligent, purposeful things (such as us!). One of Darwin's early critics called this a "strange inversion of reasoning" and that's just what it is. It inverts an ancient tradition of thought which may seem obvious, but has nothing going for it except tradition. Religious ideas have long offered comforting visions of the universe and our place in it (comforting to some, horrendous to others), but they cannot count as explanations. Until explanations come along, though, they do serve quite well to satisfy human curiosity--but I view that as no benefit. (I have much more to say on this topic in my book, Darwin's Dangerous Idea (Simon & Schuster, 1995.)

1.03.01 Mark Castonguay asked:
We live in a country were 95% of the population believes in "on high" (I fall into the 5%). I find it very difficult to discuss my position with 95% of friends, family, co-workers, etc. The "Traditional Idea" is near and dear to the heart of many loved ones. I feel I'm caught in the middle, on one hand I thoroughly enjoy defending my position and on the other I'm concerned about the feelings of others. Do you ever feel this way? If so, how do you respond? Thanks for your time.

Dennett's response:
I share your quandary. And it really is a quandary, in my opinion. For the same reason I would never dream of going around seeking out other people's children and telling them that there is no Santa Claus, I am generally content to leave other people's religious beliefs uncriticized--until they start imposing them on others in ways that might mislead or disenfranchise them. I think that the unacknowledged truth is that few people actually believe in God; many (perhaps most) who say they do actually just believe in belief-in-God. That is, they believe that belief in God is a good thing, something to encourage in oneself and others. Even an atheist can believe this! I myself am dubious that believing in God is a good thing--it does a lot of good in the world, but it also often does terrible harm--but since I am not sure, I don't go out of my way to challenge, or embarrass, people about their religious beliefs. It isn't polite, it upsets people, as you note, and no clear and present danger is thereby avoided--usually. Those who only believe in belief-in-God are, of course, the most threatened and annoyed by anyone who challenges them about God, since they are afraid we're letting the cat out of the bag.

In my classes, and when I give public lectures, I do not shrink from expressing as clearly and forcefully as I can the full implications of my position, and this often upsets people. My students know that their personal religious views are none of my business unless they want to make it my business by injecting them into the discussion, in which case, they will be subjected to the same no-holds-barred scrutiny as any other hypothesis or argument, in class or in private discussion. Students don't have to agree with me to get a good grade; they have to demonstrate that they understand the arguments and objections, and can tell good grounds for belief from bad. This works well, I find. Students who don't want to subject their religious beliefs to such a test (even in the privacy of their own minds) stay away, which is their right.

1.03.01 Mark Goldstein asked:
I find it hard to surmise that we are the results of totally random acts, trial and error. That would lead to us not having a purpose. So, if life has an architect, then WHO, WHY, and WHAT is causing motivation to be? Who benefits? Are we more than bio-computers ? Caretakers of a planet? I think there are some clues, if we study our behavior. Do inventors INITIALLY invent randomly? Doubtful. There has to be a reason to invent. Maybe some discoveries are made by mistake but the WILL that precludes the experiment or invention effects the future of what is to be. Did some computer-like intelligence create us, just like WE can now create artificial intelligence and artificial life in labs that evolve to survive? In simple words, HOW did our ancestors (the microbiotic cells) know that they had to survive? Does the EARTH itself have a will to survive?

Dennett's response:
No, there doesn't have to be a reason to "invent"--unless you are resupposing that all invention is by an intelligence (which is just what Darwin showed to be false--as I noted in response to the first question). And why should our purposes have to be inherited from on high? (I call that the trickle-down theory of importance--everything important has to get its importance from something else that is even more important.) Why can't we invent our own purposes? The idea that something valuable, meaningful, purposeful, magnificent could arise out of beginnings that happened for no reason at all is not self-contradictory or incoherent. It's just not traditional. Call it the "bottom-up" theory of importance. Try it; you'll like it.

As for your remarks about the planet and whether it has a will to survive, see my little essay "We Earth Neurons" on my web site. (LINK TO

1.03.01 Frank Giallombardo asked:
Do you believe that people are born tabula rasa? I do not believe that people are born with knowledge. They may have an innate sense or ability or talent for something, but that is not knowledge. What do you think?

Dennett's response:
Certainly people are born with a tremendous innate endowment of abilities and proclivities--far from a blank slate or tabula rasa. You agree, but deny that any of this innate endowment counts as knowledge. But the boundary between knowledge and ability (sometimes, tellingly, called knowhow) is porous at best. Suppose that every time you see a snake, you have the proclivity to feel a little shiver of fear, a sense of dislike; this is no accident, since snakes have been major predators of our nearest ancestors for millions of years. If you were to reflect upon the various things that you just don't like, you would find that most if not all of them are things that are, in fact, bad for you, dangerous for you in one way or another. If your reflections led you to the conclusion that these unliked things were bad for you, would that be innate knowledtge? It is a short step from the innate basis to the considered judgment; the judgment is, one might say, as good as innate.

1.03.01 Andrew Harter asked:
Suppose we were to someday make a machine with artificial intelligence; to what degree would we recognize it as being "intelligent" if it didn't have the same primate instincts (territoriality, curiosity, etc.) that we have?

Dennett's response:
But one of the first things I would try to build into any artificially intelligent machine is curiosity. And another is, if not territoriality, then its close kin: a powerful sense of self so that the intelligence is well-equipped to protect itself in all the ways necessary for self-preservation. These are not just "primate instincts" but what I call Good Tricks: design features that evolution has discovered again and again, and can be expected to have discovered on any planet on which there is intelligent life. (See Darwin's Dangerous Idea for a lot more on this.)

I have a lot more to say on all these questions, in my books, but also in the dozens of papers available on my web site, under Publications. See especially the last item on the list, "In Darwin's Wake, Where am I?" which directly addresses some of these questions. It was my Presidential Address to the American Philosophical Association Eastern Division, on December 29th.

1.03.01 Arlen Comfort asked:
What are your thoughts on genetically modified organisms? The kind that are intended to be passed on to the next generation during reproduction.

Dennett's response:
Every domesticated plant and animal is "genetically modified" already, and some of them have been genetically modified for over ten thousand years. The new ways of doing this do raise some novel risks, but they also hold out enormous promise, and there is no good reason to believe that the risks are unanticipatable or uncontrollable. I find the "in principle" obstructionism of many in the West to be extraordinarily short-sighted and selfish--especially since the most dramatic benefits of genetically modified crops will be (if it is done right) to those worst off in the world: impoverished Third-World people to whom pest-resistant crops, for instance, would multiply their agricultural yields by large factors, and help to diminish their reliance on Western agribusiness pesticides and fertilizers. I would rather see the activism directed to making sure that the right people control the benefits, instead of trying to ban genetically modified organisms altogether. We already know that huge harm is done to the environment by pesticides and fertilizers, and by the squandering of fresh water; genetically modified plants (and animals, including pest-control organisms) can probably alleviate these problems greatly.

1.03.01 Tom Lawson asked:
Can you give me a powerful biological example that demonstrates an increase of information or complexity by means of mutation and natural selection, in order to refute my creationist opponents' claim that the total information was already present in a plant or animal from the beginning in some more or less concealed form?
P.S: Although I'm 74, I still hope to live long enough to see a manmade conscious, intelligent machine (even surpassing human intelligence) as in W. Ross Ashby's "Design for a Brain"

Dennett's response:
The challenge from your creationist opponents is ill-defined, since it says nothing about time scale. Consider the difference between a humpback whale, say, and the sort of large terrestrial mammals (now extinct) that are the undisputed ancestors of all the whales. Humpback whales have baleen instead of teeth; all their terrestrial ancestors, of course, had teeth--none had baleen for it would not have done them any good! It takes a lot of information to divert the recipes for making teeth into recipes for making baleen. Where did it come from? From evolution by mutation and natural selection. The time it took was actually remarkably short, by cosmic standards. Mammals have spectacular rates of diversification compared to other lineages (such as insects, reptiles, mollusks). Think of all the information it takes to distinguish a mouse from a hippopotamus from a bat from a dolphin. Yet all share a common ancestor only tens of millions of years ago. Do these informational differences count as increases in complexity? Again, the question is ill-defined--but if you enlarge the timescale, there is no question that the answer is Yes. A whale is more complex, by any sane standard, than a yeast cell, yet they share a common ancestor a few billion years ago.

1.03.01 Michael Rugnetta asked:
On SCIENTIFIC AMERICAN FRONTIERS, you said that language is the one main tool that allows humans to create cultures, and that it is also the main characteristic that puts us above lesser life forms. What is your opinion on the idea of language being a poor way of communicating our ideas and that it hinders us from expressing our true thoughts, ideas, and emotions?

Dennett's response:
I'm sympathetic to the idea that "our true thoughts, ideas, and emotions" are in some ways deeper, richer, better, than anything we can express in language, but I don't think that it does much work, if any, in the controversies in which it is often raised. "You had to be there!" we say, and yes, it is true that being there, taking in the experience on all channels at once, seeing, smelling, hearing, feeling, tasting it all, gives you a richer stock of information than any verbal account could transmit, but sometimes sheer information content is not what we want. Sometimes what is most important to us is a dramatically reduced, foreshortened, distilled sample of the information. This is why we value both poetry and science. Sometimes--usually, in fact--we convey more and better by conveying less.

1.03.01 Meghan asked:
As an undergraduate student in a primate cognitive neuroscience lab, I was intrigued to hear you speak on animals' capacity to experience and anticipate either pleasure or pain, but their inability to reflect on these perceptions. I was wondering if you might expand on how you come to the conclusion that animals lack this ability? Also, how then do you explain the ability of captive animals to form lasting relationships with individual humans (relationships which I assume must be built upon some sensation of either pleasure or pain associated with that particular human)? Thank you!

Dennett's response:
The short answer to your question is that I apply the standard stinginess rule and conclude that if (1) there is no evidence that animals ever use such reflective capacities in circumstances in which using them would presumably pay off handsomely, and (2) like all capacities, such reflectiveness has costs that must be born ("paid for" in some fitness gain), the tentative conclusion must be that they don't have the capacity. Note that you are yourself relying on these very principles in drawing my attention to the animals' capacity to form long lasting relationships. Trees don't do that, do they? Nor do fruit flies (so far as we can tell!) And you would agree, no doubt, that that is good grounds (being stingy) for concluding that trees and fruit flies don't have this reflectiveness. But then I am not as convinced as you are that the long lasting relationships you mention require reflectiveness. After all, ducklings imprint on the first large moving thing they see (roughly speaking) and treat it as Mom thereafter--and this is not, apparently, a very reflective move on their part. Primates certainly have the ability to re-identify, and track, individuals, and to form preferences. That doesn't require high levels of reflectiveness. There may be some further, more sophisticated thing they can do that you are alluding to, but I haven't yet seen the evidence for it.

1.03.01 Darryl asked:
Some (maybe you?) feel that silicon-based spontaneous intelligence would not be a problem for co-existence with human intelligence given the (mostly) exclusive arenas for resource harvesting and utilization (ie: no competition). If humans are any model, there would be dire consequences. Mind amuses itself in strange ways. Emotional responses require mind (super connections at least), so why would silicone-based intelligence be any less prone to wonder, speculation, experimentation, love & hatred, self-delusion, self-destruction, etc. than humans?

Dennett's response:
Energy and living space are resources we would need to share with any alien life forms, so a sort of competition-opportunity is guaranteed. I agree with you that in all likelihood, any artificial or otherwise radically different form of intelligence would share our susceptibilities, our tendencies to overreact, to engage in unwittingly self-destructive behavior, to misjudge threats and opportunities, and probabilities. If intelligence were foolproof it wouldn't be intelligence!



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