Darwin’s strange inversion of reasoning
February 18, 2009
Daniel Dennett lecture presented as part of the Darwin Distinguished Lecture Series. These events are sponsored by Arizona State University, Office of the President, College of Liberal Arts and Sciences, School of Life Sciences, and the Center for Biology and Society.
Transcript
Paul Davies: [0:01] Good evening, ladies and gentlemen, and welcome to the 2009 Beyond Annual Lecture. My name is Paul Davies and I am the director of Beyond, ASU’s Center for Fundamental Concepts in Science. Our motto is "Confronting the Big Questions," and that’s just what the annual lecture seeks to do.
[0:19] Each year we invite a leading intellectual to present their thoughts about a deepening important topic in science of relevance to the wider community. This year’s lecture will be given by the world renowned philosopher Daniel Dennett of Tufts University.
[0:34] Unless you have been living on another planet, you will know that 2009 is the bicentenary of Charles Darwin’s birth, an anniversary being celebrated around the world. It, therefore, seemed fitting for the 2009 Beyond Annual Lecture to address the theme of Darwinism, a topic about which Professor Dennett is eminently qualified to speak.
[0:55] Dan became a household name with his bestselling book, "Consciousness Explained," which in my opinion should be compulsory reading for every student. This was followed by "Darwin’s Dangerous Idea."
[1:07] Let me give you some information about two upcoming events sponsored or co-sponsored by the Beyond Center. The first is the Shoemaker Memorial Lecture on March the 4th. Gene Shoemaker pioneered the study of cosmic impacts, and the Shoemaker lecture is on the theme of catastrophic events. So, if you are worried that we may go the way of the dinosaurs, come along on March 4th and hear Jay Melosh of the University of Arizona confirm your worst nightmares.
[1:34] The second event is a spectacular gathering of scientific talent on April the 6th when public lectures will be delivered by Stephen Hawking, Richard Dawkins, Steven Pinker, Craig "Mr. Gene" Venter, Brian "Mr. String Theory" Greene and some local superstars, too, plus a panel of these state Nobel Prize winners.
[1:55] Tonight’s lecture also forms part of the year-long ASU Darwin Fest. Ladies and gentlemen, I now invite Professor Daniel Dennett to deliver the 2009 Beyond Annual Lecture. Please join me in welcoming him.
[2:09] [applause]
Daniel Dennett: [2:19] Oh, can we have the house lights up a bit? I’ve asked for them up. I want to see who is out there. Good. Thanks very much. OK. So, I can see some faces out there. That’s good.
[2:34] Well, as Paul told you, I am a philosopher. We philosophers have to get used to the fact that some of the thinkers we take most seriously and should take most seriously were not themselves philosophers. Here is a Hall of Fame of five of the most important, influential philosophers who weren’t philosophers.
[2:54] I think you probably know the top row without any trouble. Call them out.
Audience: [2:59] [inaudible]
Daniel: [3:01] Milton, Einstein and Freud. In the next row, it’s a little harder to tell.
Audience: [3:07] [inaudible]
Daniel: [3:08] Kurt GÃdel on the left and Alan Turing on the right, but in my way of thinking the number one philosopher who wasn’t a philosopher is certainly this fellow. When I show this slide, I sometimes get some laughter [laughter] which puzzles me because I myself don’t see why anybody would think that there was any real resemblance between me and my hero. But that is, of course, Charles Darwin.
[3:44] Why was Darwin’s idea so great? I think the answer is quite straightforward. His idea, more than any other scientific idea, united the world of purposeless causation with the world of meaning, all the way from physics, if you like, to ethics and poetry, all in one unified perspective. It wasn’t just a great unifying perspective, it was a very challenging and upsetting perspective.
[4:17] After all, there had been a unified perspective in the pre-Darwinian world and a very traditional one made famous, of course, by Michelangelo on the Sistine Chapel ceiling. We can zoom in on the central panel, and there we see an intelligent designer, God, putting the finishing touches on his most intelligent design, presumably, and that’s man.
[4:44] This is, of course, the trickledown theory of creation. [laughter] I think it’s very intuitive. It’s very appealing. In fact, I think it’s an idea that has probably had a grip on us since before homo sapiens even. That is an early hominid.
[5:10] A homo habilis made very simple tools, chips, little scrapers, things like that, and homo habilis may have had some dim appreciation that it takes a big fancy thing to make a less fancy thing. You never see a pot making a pot, or you never see a horseshoe making a blacksmith. It’s always the other way around, big fancy smart things making things not quite as wonderful as they are.
[5:40] That’s the way things stood until Darwin came along, and we got the bubble-up theory of creation. Since this is Darwin’s birthday I think we really do have to quote some Darwin. So, here’s Darwin’s idea. Now, you can’t read it there, and I won’t bother reading all of it. It’s often said that it’s an argument and, indeed, it is.
[6:03] I am just going to highlight the part of it that’s an argument. This is the summary of the book, really of the theory, which comes from the end of chapter four, Origin of Species:
[6:16] "If under the long course of ages and under varying conditions of life organic beings vary at all, and if there be a severe struggle for life, then if variations useful to any organic being do occur, assuredly individuals thus characterized will have the best chance of being preserved in the struggle for life. From the strong principle of inheritance they will tend to produce offspring similarly characterized. This principle of preservation I have called for the sake of brevity natural selection."
[6:57] That’s it. That is Darwin’s great and dangerous idea in a nutshell. An early critic of Darwin, not so early actually, it was 1868; summed up the idea in a wonderful passage which I want to share with you.
[7:21] This critic was writing in high dudgeon. The capital letters were in the original. In the theory in which we have to deal absolute ignorance is the artificer. So that we may enunciate as the fundamental principle of the whole system that in order to make a perfect and beautiful machine, it is not requisite to know how to make it.
[7:44] This proposition will be found on careful examination to express in condensed form the essential purport of the theory and to express in a few words all Mr. Darwin’s meaning who by a strange inversion of reasoning seems to think absolute ignorance fully qualified to take the place of absolute wisdom in all the achievements of creative skill.
[8:15] Exactly, that’s it. He’s got it. He’s put it exactly right. That’s the purport of the theory, and it is a strange inversion of reason. I think this is very well brought out by a creationist pamphlet that was sent to me by a student. This is one page of this little propaganda pamphlet.
[8:41] Test two, it says, "Do you know of any building that didn’t have a builder? Do you know of any painting that didn’t have a painter? Do you know of any car that didn’t have a maker? If you answered ’yes’ for any of the above, give details."
[8:56] Ah-huh. [laughter] I that doesn’t show how crazy the theory of natural selection is, what would? And yet that’s exactly what the Darwinian Theory challenges. McKinsey was right. It is a strange inversion of reason.
[9:18] I showed you a picture of Alan Turing another brilliant Brit. I want to suggest that we can well understand Darwin’s strange inversion of reasoning by understanding Turing’s strange inversion of reasoning. He is responsible for another great inversion and in fact I think you will see... I’m going to try to show you, that it’s really the same inversion in a slightly different guise.
[9:42] Here it is. Here are some pre-Turing computers. A lot of them wore dresses. They were people. Mostly they were math majors, out of work math teachers perhaps. That was their job. That was their title. They were called computers.
[10:06] In the old days computers had to understand arithmetic, not just arithmetic, they had to understand mathematics. They had to appreciate the reasons for what they were doing. They were highly educated people.
[10:19] Turing recognized that this was not necessary. In fact, in a classic paper, in the classic paper, "The Birth." This is the paper which inaugurates the computer age in the same way that the "Origin of Species" inaugurates the evolutionary age. Look what he says.
[10:39] He says, "The behavior" -- he’s sort of a behaviorist -- "of the computer" -- meaning the person -- "at any moment is determined by the symbols which he is observing and by his ’state of mind’ at the moment," with the quote on state of mind, meaning he’s not going to take this mind tough stuff all that seriously.
[11:00] And what he realized is something very much like what Darwin realized. Now here’s Darwin in the words of McKinsey: "In order to make a perfect and beautiful machine, it is not requisite to know how to make it."
Here’s Turing: [11:13] "In order to be a perfect and beautiful computing machine, it is not requisite to know what arithmetic is."
[11:24] Two strange inversions. We can put them together and see how closely related they are. And in fact that’s what I’m going to try to show you more. How understanding Turing’s strange inversion helps us understand Darwin’s strange inversion.
[11:43] And notice, many people can’t abide Darwin’s strange inversion. We call them creationists. It’s not so much that they don’t believe it, although they don’t, but they can’t stand it. They have a repugnance to the idea.
[12:01] Many people can’t abide Turing’s strange inversion, either. I propose that we might call them mind creationists. Amazingly a few people seem to be both. Perhaps it’s not so amazing. Who, for instance?
[12:17] Well, who are both kinds of creationists? Well Jerry Fodor the philosopher and psychologist. And Thomas Nagel another well known philosopher of mind. Nagel kept his anti-evolutionism under wraps until just last year when he wrote an amazing and sort of dismaying article in the "Philosophy of Public Affairs," called "Public Education Intelligent Design." But then there are some other interesting varieties, too.
[12:49] For instance, the evolutionary theorists, the paleontologists Simon Conway Morris who certainly believes in evolution, except for the mind. He has recently come out with some remarkable and really almost creationist reflections. He’s famous and duly so for having been... In fact I’m going to be talking about one of his major discoveries a little later in the talk. That is the Burgess Shale fauna.
[13:22] John Searle, the philosopher, has not really made it clear how he stands on evolution, but in his discussion of what he calls "original intentionality" he’s made it very clear that he regards the mind as something that cannot be approached from below, from a mere Turingesque absolute ignorance.
[13:47] In other words, he treats the mind with what I call a "sky hook." Now, let me tell you about cranes and sky hooks. This is a concept from my book, "Darwin’s Dangerous Idea." I’m happy to say it’s caught on quite a bit. I’d love to see evolutionary theorists talking about cranes and sky hooks.
[14:09] What you have to do is imagine design space. Now design space is a logical space. It’s the space of all possible designs -- both natural, like elm trees and whales, and artificial, like BMWs and aircraft carriers and the rest. So we have this space of all possible designs.
[14:33] And then we can think of R&D, whether it is intelligent or not, as lifting in design space. After all, R&D takes time and effort and, in the artifactual world, money. You don’t get design for free. It’s possible.
[14:58] So now we can say that sky hook is a sky hook is a miraculous top-down lifter. It just hangs there in the air. It comes into existence by some sort of miracle.
[15:13] So for instance, these don’t count these are not sky hooks. It says "sky hook" right on them but somebody sent me this picture recently. Apparently some lighter than aircraft company has decided to call their blimps "sky hooks" for good reasons.
[15:30] But they are not miraculous. Those are actually a kind of crane. Cranes are do good lifting but have been put in position by non-miraculous bubble-up processes. They have to sit firmly on the foundation of previous natural processes.
[15:50] And they have to have been designed in turn by those processes.
[15:54] So now, that’s a sky hook. That’s a sky hook. This wonderful satirical drawing appeared in the "Atlantic Monthly" a few years ago. It’s called "Deus Ex Machina" by a name named Guy Billout. It’s particularly appropriate because many of you will recognize this is Brunelleschi’s Dome in Florence. And when it was first constructed it was the engineering model of the age. Nobody had ever been able to build a dome like this before. Particularly putting that lantern, as it is called, on the top was a stupifyingly grand engineering process.
[16:42] And how did he do it? Not with a sky hook but in fact with a series of cranes that he invented for the occasion. So that it was when he invented those new cranes, these new lifting devices, it opened up a whole new realm of design space that had never been accessible to builders before.
[17:04] That’s what cranes do in evolutionary biology, too. They are innovations within the evolutionary process that are major transitions as Maynard Smith and Zap called them. They open up new territory for design space explorations.
[17:24] Now, ever since Darwin, skeptics have thought I just don’t think it can be done with cranes. I don’t think the bubble-up theory can do all that work. It concedes that some design or other is just too wonderful to have evolved by gradual non-miraculous processes.
[17:45] So, these skeptics have gone out looking for things that are, as the current jargon would have it, irreducibly complex, that’s Michael Behe’s term, requiring a top-down helping hand in order to come into existence.
[18:01] People looking for irreducibly complex exceptions to the Darwinian Theory are hunting for sky hooks. That’s what you should do if you are a doubter of Darwin. You should strive to prove that something is a sky hook.
[18:17] Ironically in the 150 years since "Origin of Species" nobody has found a sky hook. But the hunts for sky hooks have often ended up discovering cranes. You start out thinking this is not possible for this to have evolved and you go to prove it and you end up discovering a new trick that evolution had up its sleeve that nobody thought or before. Ah-ha. You have discovered a new crane.
[18:45] Now, when people think about evolution can explain, there are people who are creationists. There are also people who are not really creationists, they think evolution can explain a lot. For instance, oh, yeah, evolution can certainly account for nightingales, say, but not an "Ode to a Nightingale."
[19:04] You think, wait a minute, you think a poem is more wonderful in design than a living bird? Really, you think all the intricacy of that living bird, that can be explained by bubble-up processes of natural selection, but a poem is more wonderful still? Well, maybe. But maybe not.
[19:27] What I want to do is to sketch the bubble-up path, pointing to a few landmarks along the way so that we can understand better what Darwin’s strange inversion of reason was.
[19:40] This is a cover of "Science" magazine of several years ago. What it shows is a motor protein and the reason it is on the cover is that it is celebrating the discovery that motor proteins, which march around in your cells. Nobody knew until this work whether motor proteins moved sort of like an inch worm or left, right, left, right, left, right.
[20:05] Some very ingenious experiments proved that they move left, right, left, right, left, right. In fact, there’s a wonderful video which I will show you. Now there is sound with this. I don’t know if... it’s just a little music but that’s good because I have another.
[20:26] This is inside a cell. This is a wonderful animation from Biovisions. Those are microtubules. And here comes the motor protein.
[20:46] You’ve got trillions and trillions of those little robots in you. They’re motor proteins. They’re not even alive. They are just macromolecules. They are, I’m sure you will agree, absolutely ignorant. They are marching around, carrying things around in your cells. Not a one of them knows who you are or cares.
[21:08] [laughter]
[21:12] But think, we know. We know who we are. We care. How is this possible? How do you get from absolutely ignorant, mindless little motor proteins and the like all the way to the mindful caring, wonderful conscious us?
[21:35] That’s what the bubble-up path has to explain. One of the most important events in that bubble-up path happened after life had already existed on this planet for about a billion years. It happened about 2.5 billion years ago. At this point, all there were were simple cells, prokaryotes, bacteria basically.
[21:58] And then one day something rather special happened. One prokaryote A -- oh, this will be A, I guess -- was invaded by another prokaryote, B. Well, now what?
[22:17] Was A eating B? Or was B eating A from the inside? To eat B is to take it apart and use the parts for your own devices. Well, when you are a prokaryote it’s not so easy to tell. On this occasion A didn’t eat B, A pretty much left B alone but joined forces.
[22:42] It joined forces with the cell taking advantage of all that design. Now stop and think about that. Here’s A, Here’s B. Each of these have been evolving for a billion years. You have a billion years of R&D and they are different.
[22:59] They come together and the result gets the benefit of a tremendous boost in design work, a whole lot of R&D, a whole lot of extra design is simply added right there.
[23:10] Now, it’s very important that you not dismantle B because that’s undoing all that design work. You just got raw materials then, undesigned stuff. The trick is not taking it apart but reusing it, putting it to new uses.
[23:25] Lynn Margolis, my friend and colleague from New Mass is the scientist who probably did the most to champion this idea of the symbiotic origin of the eukaryotic cell. It’s obvious today when she first pushed it, it wasn’t her idea in the first place, but she was the one that championed it.
[23:47] It’s now in the textbooks and it’s clear that this is what happened. In fact, you can see it in a hundred different ways. What you see here, you see a prokaryote on the left and a eukaryote on the right. "Eu" of course meaning better, really, good. And eukaryotic cells you see are more complicated. They just have more moving parts and those little yellow ovals those are the mitochondria.
[24:11] And they have their own DNA. And that is the most important clue to the fact that they were originally symbiotes that moved in and then they joined their fates and reproduced together. Every human cell in your body is a eukaryote. You are a eukaryote.
[24:31] And each one of those cells has two genomes -- more actually. But it’s got your nuclear DNA. That’s your genome, the human genome as in the Human Genome Project and then there’s the mitochondrial DNA, which you only get from your mother.
[24:45] And that is directly descended from this invader two and a half billion years ago. Eukaryotes are more complex than their prokaryotic ancestors. They are more talented. They just have more moving parts. That means they can be more versatile. That means that they can do some pretty amazing things.
[25:06] Now here’s a couple of sand castles. You see some sand castles made by some big fancy eukaryotes on the right. And you see a sand castle on the left that is made by a single eukaryotic cell, an amoeba. No bacterium is going to make something like that.
[25:31] This is a cell. It doesn’t have a nervous system. It’s just a single cell, but it is complex enough to make a little home like that. Eukaryotes have a versatility, in other words, that permitted a division of labor which meant that they could make multi-cellular life like us and like just about every other visible living thing on the planet are eukaryotes.
[25:56] Make us possible by this division of labor. Thus, as you know, we have stem cells which can turn into liver cells, blood cells, muscle cells, bone cells, brain cells, all these different kinds of cells because they’ve got so much complexity in them -- because they are eukaryotic.
[26:15] Now here’s a eukaryote, a little bit more complicated than an amoeba and not as complicated as us. It’s a Caddis fly larvae. And here’s what it builds to get its food in running water in a stream. This is a food sieve. This is sort of sand castle of sorts. And as you see, the water comes in the funnel, the food gets stuck on the screen there, that the larvae builds.
[26:41] Then the larvae goes and scrapes the food. It’s a really wonderful design. It compares favorably I would say with another food catching design that may be familiar to you and that’s a lobster trap, another way of sieving food from water.
[26:59] What’s the difference between those two artifacts? Well, there are reasons for the arrangement of parts in both cases. In the Caddis larvae’s food sieve and in the lobster trap. There’s reasons in both cases and they are even similar.
[27:13] But in the Caddis the reasons are not represented anywhere, not in the Caddis larvae’s little nervous system and not in the process of natural selection that track those reasons.
[27:27] Now, I call these not represented anywhere reason, "free floating rationales of evolution." And they are ubiquitous. Every adaptation, every intricate design feature of every species on the planet is the way it is for reasons that have been uncovered or tracked by evolution but these reasons are not represented anywhere until some clever scientist comes along and figures them out in a process of reverse engineering or interpretation.
[28:01] I want to illustrate this with a few vivid examples or one in particular and that’s the cuckoo chick. Cuckoos are so-called "brood parasites." The cuckoo parents do not build a nest. The mother when she is ready to lay her egg, finds a host species, a different species of bird all together, finds the nest they have just build, waits for them to lay their eggs. Then when they go off to feed, she darts down, quick, lays her egg in the host nest and rolls one of the host eggs out. That’s just in case the host can count.
[28:43] [laughter]
[28:47] Clever. Flies away, never to return. The host sits on the eggs. Since the cuckoo chick hatches quicker than the host’s chick, the first thing it does when it’s out of the egg is it tries to push the other eggs of the host species out, so that it can monopolize the food.
[29:10] I’m going to show you a little clip of this.
[29:14] [Begin Audio]
[29:14] Cuckoo’s egg looks like the warbler and the number of eggs hasn’t changed.
[29:25] Everything appears normal, but appearances can be deceiving.
[29:35] Something is not quite right.
[29:45] One chick has hatched way before the others and it is ejecting the remaining eggs.
[29:51] [End Audio]
Daniel: [29:52] Evil, huh?
[29:53] [laughter]
[29:58] But don’t worry. The cuckoo chick knows not what it does. It doesn’t need to know. Natural selection tracks reasons that creating things that have purposes but that don’t need to know them.
[30:16] Now the CIA has its famous "need to know" principle.
[30:20] [laughter]
[30:21] You tell your agents, your secret agents, as little as possible. Only what they absolutely need to know to do their mission. That way if they get captured and, oh, tortured. Now, why would anybody do that? They won’t have many beans to spill.
[30:39] Evolution has a different reason for the "need to know" principle. It reigns even more vigorously in evolution than it does in the CIA. It’s just thrift. It’s just, if you find the cheap solution where the organism doesn’t need to know, it can be the beneficiary of this design without understanding it at all.
[31:02] It can be if not absolutely ignorant, at least, mainly ignorant of what it is up to. Now, there’s a common error, not just among lay people but among even biologists of attributing more understanding to the agent than need be, when we see these amazingly clever behaviors of ants, say, or birds or fish or mammals.
[31:31] The reason we do this is we don’t have a familiar concept, any words for semi-understood quasi-representations. Or hemi-semi-demi-understood pseudo-representations. [laughter]
[31:47] There just any familiar terms for these but that’s what there are, and it’s Turing that gives us all of these. It’s Turing’s strange inversion that gives us models of competence without comprehension. Or competence with just a little comprehension. Competence with quite a lot of comprehension, but not that much, and so forth.
[32:16] Now I’m going to show you a smarter bird. This crow has been given a piece of wire and it’s trying to poke the food in the beaker and it is not succeeding. So it comes up with another idea. [laughter] Pretty good, huh?
[32:48] Now that crow is a good deal more competent than an amoeba or a Caddis fly. As my good friend, the philosopher Ruth Millikan, she speaks in a recent book about animals that represent their goals in the same representational system in which they represent their facts.
[33:10] And this would be a pretty good example of that kind of cleverness. But the important thing to note is they don’t represent the reasons for their goals or at least we have no reason to think that they do or that they can. So the need to know principle still applies only not quite as ruthlessly as before. We still have a long way to go.
[33:34] Now here’s the tree of life. It doesn’t look much like a tree to most of you until you realize that it’s a bird’s eye view of the tree.
[33:41] You are looking down from the top. The "Y" in the center of that is the root. That’s the organism that exists right at that juncture is LUCA, the last universal common ancestor of everything that’s alive today -- every bacterium, every tree, every fish, every mammal, every person.
[34:02] You see the bacteria and the Archaea, those are basically our prokaryotes. You see the limb that heads down to the bottom, those are the eukaryotes. And I’m going to enlarge this a little bit. Maybe you can see that out on the end of that twig the artist has put three fairly, relatively closely related genera together: Coprinus, Homo and Zea. That’s toadstools, us and corn.
[34:34] Your cousin, the corn. [laughter] You second cousin, the toadstool. Actually you are closer to the toadstool than you are to the corn. You share genes with all of these. We are more closely related to toadstools than we are to corn and more closely related to corn than we are to any prokaryote, to any Archaea or any bacterium.
[34:56] Now, all of that tree of life has grown in three and a half billion years. Only six million years ago we parted company from our nearest cousins, the chimpanzees, about six million years ago.
[35:18] Of course, it is very important not to say that we evolved from chimpanzees. It’s exactly as false as saying that chimpanzees evolved from human beings. Both of us have evolved from a common ancestor. They evolved just as much as we have.
[35:33] It’s important to remember that. But at any rate the differences between us and chimpanzees have had six million years to sort themselves out. Six million years of R&D, no more. All the differences that are observable today must be due to R&D occurring in that interval.
[35:53] Now I want to leap way ahead, ten thousand years in the past. This is after the dawn of agriculture. About ten thousand years ago agriculture emerged or was invented.
[36:09] Paul McCready, a visionary engineer calculated a few years ago that at the time, ten thousand years ago, the total human population on the globe plus their livestock and their pets, their domesticated animals, probably accounted to something in the neighborhood of a tenth of a percent of the by weight of the terrestrial vertebrate biomass, animals.
[36:42] It doesn’t include the insects or the worms. It doesn’t include the fish in the sea, the land animals, terrestrial vertebrates. Less than one percent ten thousand years ago. What do you think it is today?
[36:56] Any guesses? [Indistinct]
[37:01] 20, 50?
[37:02] [Indistinct]
[37:03] No, you’re a little high. It’s 98. Somebody knew. 98 percent, yes. Now most of that is cattle. In then thousand years we and our livestock have overrun the planet. It’s a shocking change. It’s a huge biological change.
[37:28] McCready has something very good to say about it. He says, "Over billions of years on a unique sphere chance has painted a thin covering of life, complex, improbable, wonderful and fragile. Suddenly we humans have grown in the population, technology and intelligence to a position of terrible power. We now wield the paint brush."
[37:51] The key of course is technology and intelligence. How did that arise? But before I turn to that question I want to compare to major events in the history of life on this planet. Stephen Jay Gould wrote a fascinating book called "Wonderful Life" about the Burgess Shale fauna, and Simon Conway Morris is one of the heroes of this book.
[38:16] This was this amazing flourishing that occurred, this so-called Cambrian explosion, which happened about 530 million years ago, early in the life of multi-celled animals and it’s when a lot of bizarrely inventive new body plans came on the scene.
[38:34] So that was the Cambrian explosion. It occurred about 530 million years ago and the explosion took place over a very short period of time, well, several million years. Geologically, a short period of time.
[38:47] The McCready explosion only 500 generations, 500 human generations. Now that’s an explosion. It’s not just genes. It can’t be, not in 500 generations. In fact, it’s due to a second information highway from parents to offspring.
[39:08] There’s the traditional Darwinian gene highway, the vertical gene transmission. Vertical, meaning descending from parent to offspring. But then there is a second highway, the vertical cultural transmission from parent to offspring, the stuff you learn at mother’s knee or doing hunting with dad and so forth.
[39:30] Now, in a wonderful book by Pete Richerson and Rob Boyd called "Not By Genes Alone," they talk about the conditions under which this second highway would be built and what would happen once it was built. So the cultural highway, once it’s in place it can be invaded. It reminds you of the Internet, spam and things like that.
[39:52] Once in place it can be invaded and you can get what they call oblique transmission. That is, not from parent-to-offspring but from next-door-neighbor to offspring and peer-to-offspring and demagogue-on-the-street-corner to offspring.
[40:07] You get in short what they call "rogue cultural variance." These rogue cultural variants have another name, perhaps more familiar, introduced by one of your earlier Beyond speakers, Richard Dawkins that’s what he calls "memes."
[40:29] Memes are analogous to genes in the sense that they are the vehicles of information. This is cultural information, not genetic information. As he points out they are like viruses. What’s a virus? It’s a sort of naked gene. It’s pretty much all gene.
[40:48] Or as I like to say, a virus is a string of nucleic acid with attitude.
[40:53] [laughter]
[40:55] It’s not alive. It’s just a macro-molecule. It’s not unlike those motor proteins. It’s absolutely ignorant. But it happens to be blessed with a shape that gives it a power to do an amazing thing. It finds its way into a cell, commandeers the copy machinery of that cell and gets that cell to make copies of it rather than of the cell’s own DNA.
[41:29] That’s how viruses replicate and of course they are objects of natural selection without any doubt at all. HIV, a well-known virus, has evolved more if you simply look at its genome and compare its genome today with its genome when it was first sequenced just years ago. In that time there has been more time in the HIV genome than there has been in the human genome since we parted company with our common ancestor with the chimpanzee.
[42:04] Does evolution happen? You bet it does. Well, now a meme is a data structure made of information with attitude. So it’s the same sort of thing as a virus. It doesn’t get into a cell to get copied. It gets into a brain. And exploits the brain’s tremendous capacity for being a copy machine to make more copies of itself to get rehearsed and rehearsed and rehearsed and then broadcast out into the world.
[42:32] Now, there is a wave, a wall, a prevailing wind of repugnance and skepticism to the idea of memes. Both among people in the humanities and social sciences and even among a lot of hard bitten evolutionary biologists. They are not sure about this idea at all.
[42:52] One of the most common complaints I get. They ask what evidence is there that memes even exist. We know genes exist, what makes you think memes exists? What evidence is there that memes exist?
[43:04] Well, I have a new way of dealing with that. First of all how many of you believe that words exist? Are there words along with the rest of the things in world? I certainly think words exist. Well, words are memes that can be pronounced. They are simply a subset of memes.
[43:23] If you believe in words then you believe in memes. It’s as simple as that. Now I’m not going to have time to defend that hypothesis that claim in detail here because I want to talk about what follows from it instead of how to defend it.
[43:39] What follows is that we are basically apes with infected brains. Or a better way of saying it is that we are eu-primates, like eukaryotes. Our brains have been invaded by virtual machines. That’s the memes, designed by natural selection. And these virtual machines give us powers that give us the versatility that take organization up a level.
[44:08] When you take in a meme, you’re taking in something that is the product of a lot of R&D. And you just, boom, you just help yourself to it. You don’t have to reinvent the wheel. You don’t have to reinvent calculus. You don’t have to reinvent maps, or writing, or reading, or cost-benefit analysis, or alphabetizing words, or any of the other things that you learn. Those are all memes. You get these beautifully designed virtual machines. You just pack them into your head, no R&D cost to you, or very minimal.
[44:43] Our power, the power that made the McCready Revolution happen, or explosion happen, depends on the culture that permits us to divide labor and share expertise. We’re not all engineers, we’re not all doctors. Some people are biologists, and others are cooks, and others are farmers, and so forth.
[45:01] From this perspective, we can see that both spider webs and power grids, worldwide web, these are artifacts made by eukaryotes. They were all fruits on the tree of life, both the beaver dam and the Hoover Dam, both the bird’s nest and the "Ode to the Nightingale." These are artifacts all. But the ones on the right, the human ones, are rather different in that they are made with this extra important ingredient, all of the design, all of the mind tools that come from cultural evolution.
[45:41] Now I want to describe the delicate transition from bottom-up Darwinian R&D to top-down creative genius-type R&D. One of my favorite sayings from a former student of mine, "You can’t do much carpentry with your bare hands. You can’t do much thinking with your bare brain." What you need are thinking tools. Fortunately, there’s a lot of them hanging around. All you have to do is pick them up and install them.
[46:10] In other words, words are tools. They’re not the only tools, they’re not the only memes, but I’ll concentrate on them. Words are not always elements of grammatical construction. Sometimes they have standalone uses. For instance, passwords and labels are wonderful little devices for accomplishing, for speeding up jobs. They’re great little cognitive crutches. We didn’t design them, but we benefit from the design.
[46:39] In Doug Hofstadter’s 2006 book "I Am a Strange Loop" he gives a little tool kit. Here are some of the tools in his tool kit. And I think you will recognize that they’re very good tools for special uses. Wild goose chases, tackiness, dirty tricks, sour grapes, elbow grease, feet of clay, loose cannons, crack pots, lip service, slam dunks, feedback. Each one of these little gems is a tool that can be used to think about things, to make analogies, to see similarities, to make more efficient and vivid and swift your thinking on many topics. These are sort of prosthetic aides to cognition.
[47:30] He didn’t design any of them. He just helped himself to them and he just uses them. They’re tools made of technique. They’re sort of recipes for action. They’re rather like java applets that you get over the web. You download them and they give your computers new powers. What are java applets made of? Well, they’re made of bits. They’re just made of information. Now, memes aren’t made of bits, but they are made of information. And they’re downloaded into our minds in a way not unlike java applets.
[48:07] What’s long division made of? It’s a pretty good tool. You’ll remember that you probably learned how to do it, thanks to English. You have, if you like, an English virtual machine which enabled you to download the long division machine with a little practice. What’s cost-benefit analysis made of? It’s a bigger tool, a bigger applet. So these virtual machines are made of information. It’s this technology that remade the brain, and it makes our minds. That’s what our minds are made of. Lots and lots and lots of these tools.
[48:43] Well, who designed all these treasures that we have? We know that some of the wonderful things that we get from our culture have individual, nameable authors. And we honor them, and we carve their names in the side of the library wall. It’s Pythagoras, and Plato, and Descartes, and Newton, and Shakespeare, and Jane Austin, and Madame Curie, and a lot of other great authors of wonderful designs that we treasure. But most of the treasures that we download in this way, have no author at all. Nobody designed language. Nobody designed tonal music. Nobody invented maps. Nobody invented money. These things are products of natural selection, natural cultural selection.
[49:29] "Well then," you may say, "I don’t know if I like this vision. What am I? Who uses these tools?" You might think what you are is a sort of Cartesian ego with original intentionality. No, that’s, I think, a hopeless idea. But I won’t try to argue for it here. I’ll simply say what the alternative is, which is the proper Darwinian and Turingan - Turinganian? Turingess? I don’t know, Turing. What you are is an alliance of hemi-semi-demi-understood quasi representations. Your mind is a virtual machine made of smaller, simpler virtual machines. And it guards the entrance and evaluates yet other virtual machines.
[50:22] In the "Origin of Species," Darwin opens the book - it’s a wonderful read, by the way. It’s a real page turner. Amazing, it’s great literature in addition to being great science. It’d be fun to read this year, or reread. And he opens the book talking about methodical selection. How plant and animal breeders with foresight, with intent, set out to improve the breed. To make faster racehorses, more beautiful pigeons, smarter bird dogs, and the like.
[50:52] And then he points out that before there was methodical selection, there was what he called unconscious selection. This is where people, by their actions, changed their domesticated species. Not with intent and not with foresight, but just by ignoring the runts of the litter, favoring the best, or what they thought were the best, and over time this led to changes, improvements, large scale changes in domestic species. He calls that unconscious selection.
[51:23] So we start off with, if you like, intelligent selection, then we get selection which isn’t so intelligent, in fact it doesn’t need any intelligence at all, and then he goes and segues from that into natural selection. Notice, all three of them are varieties of natural selection. Methodical and unconscious selection are just natural selection where the selective force is one particularly vigorous species, namely us.
[51:48] More recently, thanks to our culture, we’ve invented another variety. We have a quartet now because we’ve added genetic engineering, which is just like methodical selection except that you don’t wait around for chance to give you the genomes that you want, you construct them directly. But then you let them loose and see if they can survive and as often as not they can’t because evolution is cleverer than you are.
[52:17] We can do the same with memes. The original memes were naturally selected. These were what I call synanthropic memes. Synanthropic species are the species that live with us but are not domesticated. They’re wild but they live with us, sometimes off us. For instance, rats, mice, cockroaches, barn swallows, pigeons, squirrels, bedbugs, those are synanthropic species. They live, syn, with anthropus, with human beings.
[52:58] But we’re not taking care of them. We’re not shepherding them. We’re not domesticating them. They’re just well designed by natural selection to thrive in our company. Well, there’s memes like that as well. Superstitions would be a good example.
[53:17] Then there’s unconscious selection. For instance, the differential replication of tunes. These are folk tunes going back into the mists of prehistory and only the most vigorous, unforgettable, memorable, lilting, enchanting tunes get copied and copied and copied and spread.
[53:36] Nobody is trying to spread them. Nobody is trying to anthologize them or make money off of them. They just spread because they can by unconscious selection. The Germans have a nice word for tunes like that. They call them "ear worms."
[53:50] You know one of those jingles you can’t get out of your head. And then you hum it and you pass it to your neighbor who now hates you because she’s got it running through her head and so forth.
[54:03] Then we have the methodical selection of domesticated memes. It’s very important. A lot of people don’t like memes because they think all memes are just the first two categories, but no. Science is made up of memes. Literature is made up of memes, too.
[54:18] A good example of this I think is calculus. Because it’s like laying hens. Laying hens would go extinct if it weren’t for the patient help of human farmers because the broodiness has been bred right out of them. They would not sit on their eggs and incubate them. So you have to have incubators.
[54:36] Calculus is sort of the same way. You have to work hard to get it to reproduce. [Audience laughs] I don’t know. Maybe here in Phoenix it’s not that way. I mean, do you find that calculus is just infectious, just can’t get it out of my head? It’s just, oh, man, hum those second derivatives, you know.
[54:57] [laughter]
[54:58] I don’t think so. I’m sure every math teacher and every science teacher wishes it were true but it’s not. And of course we have mimetic engineering. That’s spin doctoring, advertising and the like, slogan-eering, try to design memes that will go viral, that will spread around in the culture. And, of course, we’re not very good at that, thank goodness.
[55:23] What all of these memes permit us to do is a certain kind of bootstrapping that’s happened in the past and it will work again and again and again in the future.
[55:32] I’m going to give you one example. How do you draw a straight line? It’s very simple. You get a piece of paper and a pencil and a straight edge. And you draw the line against... you put the pencil on the straight edge and you draw the line.
[55:49] Where did you get the straight edge? Oh, well you got it from the straight edge maker. How did he make the straight edge? Well you see he had this straight edge and a piece of metal and he put it down and he... And where did he get the straight edge that he used? Well, from another straight edge maker and so forth.
[56:08] But not ad infinitum. In fact, there’s an interesting book out on the history of straight edges.
[56:17] [laughter]
[56:19] And it’s an evolutionary process. Here’s a diagram. Here’s a picture from it. This is a circa 1960 boxed straight edge. It’s about as good as you can make it at the time. And the caption says it is self proving because of its shape. That is, it doesn’t tend to distort. Not subject much to thermal expansion or distortion.
[56:40] The same book has a diagram, which I love. What you see here that wiggly line is the imperfections in a gauge block. This is about the finest straight edge that could be made back in the late ’60s, and it doesn’t look very straight, does it, when you magnify the imperfections by a factor of a million.
[57:01] But look what’s happened here. Here, we have a representation of the goal and the reasons for the goal. Here we have representations of the falling short of the goal. If you understand and represent your purposes, then you can measure how far off your successes are from your failures.
[57:23] What’s happened is that the ideal of a perfectly straight line... Plato might have called it the "form of the straight." It was arrived at by approximation, both of the artifacts and of the ideas. As they made better and better straight edges, they had a better and clearer idea of what a straight edge was and what a really straight edge was, and they could measure how far short of the perfect straight edge their straight edges were.
[57:47] It’s this kind of approximation, the bootstrapping approximation, that was made possible by cultural evolution. The form of the true has a similar history. Science consists of structures of memes that have been designed to permit the selection for veridicality. By in large if a meme is true, it’s accepted. If it’s false, it’s eventually rejected.
[58:14] It’s not perfect, of course, any more than a straight edge. There are lots of mistakes. But the point is that it is a refined system designed to get at the truth.
[58:25] In closing, then, what makes us human, I’m claiming, is not so much our genetic children but our brain children. We, alone, of all the species on the planet represent our reasons.
[58:40] We can think about our values, our reasons and this is the source of our creativity. We have finally reached genuine intelligent design. It’s not perfectly intelligent, but it’s pretty darn intelligent. We are the first intelligent designers in the history of evolution.
[59:04] And now we, the reason representers, can look back and discover the reasons everywhere on the tree of life that weren’t represented. It took Darwin to figure out that a mindless, purposeless process discovered all of those reasons. We intelligent designers are amount the effects, not the cause, of all those purposes.
[59:28] Now, if you look real close, you can see that I have a little pin up here. It’s a Darwin pin and my other predecessor is the Beyond lecturer, Murray Gell-Mann. He saw me wearing this pin to a meeting a few years ago and he said, well Dan you know that the Christian fish is the first acronym that the Greek word Icthus, you see it there, the Greek word for fish is why they use the fish.
[59:57] But the Icthus is an acronym and it stands for Iesous Christos Theou Huios Soter - "Jesus Christ, God’s son and savior." That’s why the Christians use the fish. I said I said well, I think I had heard that, Murray. That’s nice. That’s great.
[60:14] He says, yeah, but what I want to know is what does DIRWYN stand for?
[60:17] [laughter]
[60:22] Well, I’m not the poly-math that Murray is but I did have some high school Latin so I said well, let me work on that. I went and got a cup of coffee and I worked on it a little bit. I came back a little later. There’s no "W" in Latin so you have to use double "U."
[60:39] [laughter]
[60:42] Yeah. So here’s what I came up with. Delaray oak torum rearum, ut Universum [laughter] infinitum noscas. "Destroy the author of things in order to understand the infinite universe."
[61:09] [applause]
[61:09] Thank you for your attention.
Announcer: [61:16] This lecture is part of the Arizona State University, Darwin Distinguished Lecturer Series. It is sponsored by the ASU Office of the President, the College of Liberal Arts and Sciences, the School of Life Sciences, the Center for Biology in Society. And is a production of Grass Roots Studio.
Transcription by CastingWords