BookTalk.org

Please use this thread to discuss the above listed chapter of "Darwin's Dangerous Idea: Evolution and the Meanings of Life" by Daniel Dennett.

Here is where we get to the controversy with Gould. I must say I was gravely disappointed with Dennett's side. I recently saw a Facebook GIF in which Dennett was quoted on how to argue persuasively, and he emphasized making sure the other person's point is understood. He said that when you can restate it so clearly that the other person wishes they had said it that way, then there is no chance of the discussion derailing over misunderstanding.

Well, let's just say that no such attempt is in evidence in this chapter. Let me start by pointing out the nature of the mechanism in speciation which is at the heart of the model of punctuated equilibrium. The cite provided by geo does an excellent job:

http://evolution.berkeley.edu/evolibrar ... ctuated_01

Basically the idea is that in a small, isolated population, slight advantages are amplified within the gene pool, so that the character of the pool itself is able to shift rapidly.
Dennett brings out the reasoning by which Gould claims that punctuated equilibrium sets up a challenge to modern Darwinian orthodoxy: speciation provides the raw material for selection, rather than the reverse told in the standard approach to explaining the process. Dennett wiggles uncomfortably around this point, but never engages it directly.

Dennett has, essentially, two responses to the challenge presented by long-term equilibrium. First, he asserts there is no real difference: punctuated equilibrium only challenges "constant speedism"; if you look closely at the time scale of speciation there will still be gradual drift within the space of possible strategies; Gould himself acknowledges speciation which does not fit the stasis pattern, so it is only part of the picture; and adaptation is still part of the mechanism in punctuated equilibrium. The second response is that we are unable to tell whether speciation is a process from outside the basic gradualist mechanism or whether it only appears to be because of incomplete evidence. (My only response to the second point is that Dennett has not bothered to give enough context to allow us to decide whether he is in fact making a relevant point in a controversy between two perspectives.)

As for the "no real difference" arguments, it seems to me that each individual point Dennett makes is essentially true about it, but that they are all beside the point. Maybe Gould did claim too much revolution for his insight, but the point is that it is new, substantial and challenges important implications of the received view, notwithstanding Dennett's points. What he does not say is more telling than what he does: Dennett makes no effort to assess whether gradualism was the norm in describing evolution before, and whether the "standard story" has changed (it has.) In other words, has long-term equilibrium modeling changed the terms of the discussion and the salient features for which scientists look? I would say the answer is yes, but Dennett does not engage it on such standard grounds of History of Science or even Philosophy of Science. Instead, he argues very much like someone with an ax to grind, even attacking the now-standard vocabulary term "spandrel" on quibbling grounds which do not address the main point (i.e. many biological features are by-products of real adaptations and not adaptations themselves).

In the process of this tendentious argumentation he makes several assertions which are truly unfair.

The first which struck me was in his incompetent effort to resolve the question of saltationism (between the section on Goldschmidt and the one on "constant speedism.") He approaches it as a Medieval scholastic, trying to track down whether Gould did or did not argue for "macromutation" or "saltation." In the process he quotes a key Gould argument and lets it drop undiscussed: the "creative" source of speciation is variation, with selection only acting negatively upon it. At this point it might be good to review the video: a species of snail with short, medium and long shells is able to evolve into a long-shelled population by selective pressure on a small, isolated population, whereas in the larger population the advantage might not be sufficient to matter much over the relevant time scale. I have read a lot of Gould's "Natural History" essays, mostly collected in books, and the key role of variation is a constant theme of his. Yet this actual process involved in Gould's thinking on the primacy of relatively quick speciation, and its challenge to gradualism, is given one sentence by Dennett in favor of three pages of "did he or didn't he" discussion of what Gould said about "leaps."

Gould had one marvelous case study, for example, (reporting the work of others), on the way a population shifted its character in response to a cycle of rain and drought. In the drought years one set of characteristics preferentially survived, in the rainy years, a different set did, and the population proportions shifted dramatically as a result, but within something like 1/3 to 2/3. If the population did not maintain variation, it would not be "well adapted." Anyone who has worked with plant or animal breeding knows there is a lot of latent variation in a population and you get to an outcome like seedless grapes or skinny dogs by ruthlessly selecting for the fraction of a population which leans toward the desired goal.

Gould argued, if I understood his work correctly, that relatively infrequent "allopatric" events which broke one part of a population off in a dramatically different environment from that of the parent population were responsible, in the main, for speciation. This is a rather different view from the one in the textbooks I grew up with, which said random mutations eventually produced one that was important enough to generate a new species, a "macromutation" argument, or perhaps eventually accumulated sufficient differences "sympatric"-style, to emerge as dominant. Thus Gould gives primary roles to pre-existent variation, and to contingent events, which were absent from an all-adaptationist, all-gradualist version of the matter.

Dennett likewise dodges the point on "trimming the tree" of life. While his critiques of the Burgess Shale reading by Gould are fair enough, though relying on Simon Conway Morris' re-evaluation of his own work on which Gould based his reading, Dennett simply ignores the implications for gradualism of the series of failed branches ignored by the "spreading cone of life" diagram typical in presentations of evolution.

Gradualist adaptationism has no place in its story for the many types of hominids, for example, who started out with promise but didn't last all that long. In the gradualist schema, Neanderthals would become homo sapiens, but we know that did not happen. Presumably one could put together a post hoc account that gradualists would have no objection to, but the point is that a framework which always assumes that every feature is a good adaptation then has no handles for asking questions about contingent events. Maybe they were just wedged aside by new hominid groups who could speak more effectively, but at a minimum such an explanation should account for why the better speaking grew up in an offshoot of population A and not among the Neanderthals themselves. The punctuated equilibrium story offers a series of things to look for which might provide such an explanation. Gradual adaptationism simply doesn't. It must have been a mutation, in that framework, and the best we can hope for is to find evidence of a crucial mutation.

More a matter of nastiness, Dennett's treatment of "wedges" (Gould supposedly distrusts Darwin's notion that superior close relative species drive out inferior ones by eating more of the available food) reaches the bizarre conclusion that Gould does not like them because he prefers skyhooks to cranes. On what grounds? Because Gould disparages the "plodding predictability" of the wedge, which Dennett goes on to recast as its "mindlessness." Gould, whose aversion to plodding predicability can be completely accounted for by his emphasis on contingency and occasional, sudden speciation, is from nowhere accused of preferring that a mind be involved. In fact Gould invariably criticizes heavily any suggestion of intention or mind in the process.

The last, and most serious, distortion is Dennett's unfounded conclusion that Gould prefers to escape from cranes in favor of skyhooks. There is simply no evidence for that. In the middle of Dennett's discussion of it he quotes Gould, agrees that there is no difference between Gould's view and that of the most mechanist of Darwinians, and then proceeds to claim that Gould criticism of hyper-Darwinism is a criticism of those who reject skyhooks. Furthermore, he makes an attempt to "out" Gould as a closet theist, (I use the terms advisedly - in academia today you are much more likely to be turned down for a job for expressing religious views than for being gay), on the basis of nothing. Gould (gasp) is fond of quoting the Bible (though not nearly as fond as he is of quoting Darwin, Cuvier, Lyell, Agassiz and Huxley)! Does he quote it for scientific authority? Not once. Gould believes science does not address ultimate origins, and evolution does not explain the origin of life. OMG! Can you imagine! He must think Goddidit! Considering the nature of the claim, and the background of reasoning behind Gould's statements, if that is the best Dennett can do for evidence he should be deeply ashamed of himself. And if it isn't the best he can do, why, pray tell, did he leave out the real evidence?

He is much closer to the mark when he draws the connection between Gould's views and his politics. Gould probably overdid his rejection of the notion of "progress" in evolution, but his emphasis on random, not progressive, evolution is heavily influenced by his acquaintance with Social Darwinism and the general abuse of Darwinian notions to justify eugenics, racism, sexism and several other hateful ideologies. When we get to the discussion of sociobiology, several types of connections between his emphasis on contingency and his skepticism of adaptationism will become more plain.

Finally I would like to underline what I think was a good treatment of Gould's work, on the subject of replaying the time line. Gould asserted that the results would quite possibly be totally different if you replayed the tape. And, while there is a grain of truth in that, Dennett's response is cogent and very relevant: the same fitness hills are likely to be climbed. Eyes will evolve, fins or flippers will evolve among the aquatic species, flight will evolve.

If I was trying to make something of Gould's point I might argue that intelligence would evolve among the cephalopods or the plesiosaurs (or whatever took their place) as early as among the mammals, or that the absence of tiny mammals living at sea may be an indication that in slightly different circumstances there would be no mammals at sea at all, or that social insects might be the dominant species in a different replay. Of course we have no way of knowing, but the chances are that the same kinds of niches would be filled by somewhat similar types of creatures. Even a radically contingent view of life must deal with some of the constraints created by reality.

Harry Marks wrote: . . . Gould argued, if I understood his work correctly, that relatively infrequent "allopatric" events which broke one part of a population off in a dramatically different environment from that of the parent population were responsible, in the main, for speciation. This is a rather different view from the one in the textbooks I grew up with, which said random mutations eventually produced one that was important enough to generate a new species, a "macromutation" argument, or perhaps eventually accumulated sufficient differences "sympatric"-style, to emerge as dominant. Thus Gould gives primary roles to pre-existent variation, and to contingent events, which were absent from an all-adaptationist, all-gradualist version of the matter..

Thanks, Harry. I've never really understood the nuances of the dispute between Dawkins and Gould, but thanks to this incredibly well-written post, I believe I now have a handle on it. Dennett, I believe, has always favored Dawkins, and vice versa, and I can only imagine that he has taken up the gauntlet on Dawkins' behalf. At any rate, as much as I admire Dawkins, his dispute with Gould was clearly dogmatic in nature. And it seems to me he resorted to the same kinds of ad hominems and circuitous reasoning with respect to punctuated equlibirium that Dennett seems to be doing here. It's hard to imagine what Dennett thinks he's doing. Gould was still alive and well at the time Darwin's Dangerous Idea was published. I wonder if he ever responded to Dennett's aspersions. I'll bet he did.

Thanks again for a very finely written post. I look forward to catching up. I believe that there have been a lot of misconceptions about punctuated equlibirum over the years, especially the distortions put forth by the creationist community. It's interesting that you say Dennett doesn't give enough context for us to determine whether or not he's in fact making a relevant point. I'll see if I agree with you.

Gould was never very subtle about his beliefs, and based on years of reading Gould, I am skeptical that he ever preferred skyhooks to cranes. I'm very interested in seeing how Dennett comes to make that claim.

A funny thing, one of the books currently distracting me from Dennett (besides David McCullough's book, 1776) is Stephen Gould's Dinosaur In A Haystack, a collection of essays. What I didn't realize until recently is that most of Dennett's books collections of essays were published in the magazine Natural History . And there is a definitely order to them. Bully for Brontosaurus, for example, was his fifth collection and Dinosaur In A Haystack was his seventh. Gould is a fantastic writer, always a good read.

I'll go even further on this tangent by mentioning the first essay in Dinosaur In A Haystack, which concerns a solar eclipse Gould witnessed in 1994. As you may know, we are due for another solar eclipse this August 21. I mentioned my recent move to Franklin, NC, which just happens to be in the path of totality. So if anyone wants front row seats to this eclipse, please stop by Franklin, NC on Aug. 21. We have a nice lawn and a great view of that area of the sky (weather permitting, of course). A good time is guaranteed for all.

geo wrote: Thanks, Harry. I've never really understood the nuances of the dispute between Dawkins and Gould, but thanks to this incredibly well-written post, I believe I now have a handle on it.

Well, I am happy if I have made anything clearer, but I am actually pretty ignorant about Dawkins vs. Gould. I read up on the controversy over Gould's "Non-Overlapping Magisteria Argument" (NOMA), where I think Dawkins is dead wrong in his reading of Gould, but I think we hashed that out on this forum many years ago. On the topic of evolutionary mechanism, I vaguely gather that two big egos clashed more over who revolutionized more, rather than over any real substance. Dawkins' observation that Gould only criticized "constant speed-ism" is, as I said, probably true but rather beside the point.

I suspect their very different reactions to sociobiology may be at the root of the differences, and more may be said about that as we move into further chapters.

geo wrote: It's hard to imagine what Dennett thinks he's doing. Gould was still alive and well at the time Darwin's Dangerous Idea was published. I wonder if he ever responded to Dennett's aspersions. I'll bet he did.

Thanks to a reference near the beginning of our reading of this book, we were directed to a review in the New York Review of Books
http://www.nybooks.com/articles/1997/06 ... mentalism/
in which Gould is rather uncomplementary but does not address the personal insinuation of "preferring skyhooks", being more upset by John Maynard Smith's about face from engaging Gould's work assiduously (if critically) to dismissing him as hardly worth responding to.

I am also at a loss for understanding where Dennett is coming from, but the pettiness is breathtaking.

geo wrote:Gould was never very subtle about his beliefs, and based on years of reading Gould, I am skeptical that he ever preferred skyhooks to cranes.

So your reading is the same as mine.

geo wrote:I'm very interested in seeing how Dennett comes to make that claim.

I wish I could promise you that your interest would be rewarded by something interesting.

geo wrote:As you may know, we are due for another solar eclipse this August 21. I mentioned my recent move to Franklin, NC, which just happens to be in the path of totality. So if anyone wants front row seats to this eclipse, please stop by Franklin, NC on Aug. 21.

Thanks, I will mention it to our friends in the Raleigh-Durham area.

Punctuated equilibrium raises an interesting problem in evolutionary teleology. It appears that in a stable niche, organisms will evolve quite rapidly to fill it, and then there will only be tiny incremental change until something disrupts the stability. Over evolutionary time, the ability to fill the available gene space is strong, and the change to this gene space is the driver of speciation. So the telos of the gene space is the boundary of adaptation, limiting the potential of existing genes to exploit the opportunities offered by a stable environment. Only when the gene space changes, with a punctuation to the equilibrium, ranging from the entry of a new predator or pathogen, a change in climate, to a catastrophic extinction event, does potential emerge for significant speciation, beyond the simple linear change such as growth or shrinkage in size and gradual increase of camouflage caused by mutation in a stable situation. The non-linearity of speciation requires an external disruptor.

Robert Tulip wrote: It appears that in a stable niche, organisms will evolve quite rapidly to fill it, and then there will only be tiny incremental change until something disrupts the stability. Over evolutionary time, the ability to fill the available gene space is strong, and the change to this gene space is the driver of speciation.

I think Gould and Eldredge would argue that speciation drives the change in gene space (assuming I am interpreting "gene space" correctly as "the set of all genetic combinations present in some species capable of reproduction"). Of course both sets of constraints must be satisfied: there must be adequate potential within the gene pool to fill the niche (sea birds could not fill the niches that Darwin's finches radiated to fill in the Galapagos, predators could not just spontaneously arise to consume the tasty morsels of dodobirds on Mauritius,) and there must be a new and isolated opportunity.

We tend to be very impressed that there is any speciation at all, since all we see around us is stability. Gould and Eldredge had us take a step back and note that stability is, in fact, the normal case even over geological time scales. What's going on may be that the happy accident of genetic potential meeting a new opportunity niche may be a very rare event (though it has happened to hominids at least six times in the last two million years - maybe it isn't all that rare but the apparent successes run into disastrous environmental variation relatively often, so that often catches them before they leave much fossil record).

Robert Tulip wrote: So the telos of the gene space is the boundary of adaptation, limiting the potential of existing genes to exploit the opportunities offered by a stable environment. Only when the gene space changes, with a punctuation to the equilibrium, ranging from the entry of a new predator or pathogen, a change in climate, to a catastrophic extinction event, does potential emerge for significant speciation, beyond the simple linear change such as growth or shrinkage in size and gradual increase of camouflage caused by mutation in a stable situation. The non-linearity of speciation requires an external disruptor.

I like the idea of a boundary of adaptation. It should be kept in mind that the boundary may be a matter of evolving harpoons in single-celled creatures, or coevolution of advances in digestion with microbiota, rather than always "faster, smarter, keener". But I suspect that this version of telos, like Dennett's "adaptation hills" may act sporadically if relentlessly.

I was listening to the BBC's "Why Factor" on "Why some people choose childlessness" as I drove around the capital city today. They noted that the ability to choose childlessness if you have a sex drive is relatively new. And I wondered if, in twenty generations or forty, childlessness by choice would be totally bred out of people. I rather suspect not. Not only does the childless person often contribute to the reproductive fitness of relatives, but the variation may continue to arise spontaneously. This is Gould's big obsession - variation is the byword of biology. You might think nothing is as ruthless as chosen childlessness in weeding out its genetic basis, but the genetics of such a trait may be very complex. It might, for example, be strongly associated with intelligence, (the BBC says women who find alternative sources of fulfillment are much more likely to choose to remain childless), in which case some of the people in that category go ahead and have children, with very high reproductive success because intelligent people have good options in the mating game.

Robert Tulip wrote:Punctuated equilibrium raises an interesting problem in evolutionary teleology.

One thing Dennett has succeeded in is convincing me that "telos" is a very problematic concept. I am currently reading about memes, and whether it can be said that brains and computers are just hosts co-opted by cultural memes for their own reproduction. Makes my head spin, especially when I think about, for example, the virus spread in cat litter boxes which seems to influence human brains to be attracted to cats.

Harry Marks wrote:I think Gould and Eldredge would argue that speciation drives the change in gene space (assuming I am interpreting "gene space" correctly as "the set of all genetic combinations present in some species capable of reproduction").

‘Gene space’ is just a phrase I came up with to try to help picture the geometry of evolution. I don’t know if it makes sense, but I was thinking of gene space as meaning more the set of all genetic possibilities rather than as present combinations. So it is a trans-temporal idea, indicating where the present gene set could possibly go in the future, as the potential rather than just the actual. So the gene space of the savannah includes a giraffe with a very long neck nerve, (per Dawkins’ discussion of giraffe evolution). I am using gene space as a way to think about punctuated equilibrium, seeing a system where the potential gene space is fully occupied – like sharks which have been the same for tens of millions of years – as providing the basis for equilibrium.

Harry Marks wrote: Of course both sets of constraints must be satisfied: there must be adequate potential within the gene pool to fill the niche (sea birds could not fill the niches that Darwin's finches radiated to fill in the Galapagos, predators could not just spontaneously arise to consume the tasty morsels of dodobirds on Mauritius,) and there must be a new and isolated opportunity.

And the key point that Gould makes is that the occurrence of new opportunities is decisive for evolution, punctuating the grammar and geometry of planetary history. As we all know grammar without punctuation loses a key element of causal logic

Harry Marks wrote: stability is, in fact, the normal case even over geological time scales. What's going on may be that the happy accident of genetic potential meeting a new opportunity niche may be a very rare event (though it has happened to hominids at least six times in the last two million years - maybe it isn't all that rare but the apparent successes run into disastrous environmental variation relatively often, so that often catches them before they leave much fossil record).

Your point about disastrous variation makes me think of that science fiction story (can’t remember specifics but perhaps Arthur C Clarke) about how as soon as intelligence evolves it goes extinct due to its extreme instability. To me that is a key argument for religion, as the framework of natural order enabling evolutionary survival, to cross the dangerous and difficult evolutionary threshold from instinct to reason and control our selfish genes. That is entirely how I read the Bible.

Harry Marks wrote: I like the idea of a boundary of adaptation.

Putting on your economic hat, I wonder if you think a boundary of adaptation may be analogous to the production-possibility frontier? All the accidental mutations in an ecosystem push to reach the telos of the system potential, but may reach it in slightly different ways, hence the boundary forms a connected genetic line https://en.wikipedia.org/wiki/Productio ... y_frontier

Harry Marks wrote: It should be kept in mind that the boundary may be a matter of evolving harpoons in single-celled creatures, or coevolution of advances in digestion with microbiota, rather than always "faster, smarter, keener".

That is just a statement that Darwin’s ‘descent by modification’ was misconstrued through Spencer’s use of survival of the fittest to wrongly imply a purely competitive rather than cooperative model of evolution. Again, my use of evolution as a religious heuristic, seeing salvation as survival, recognises the essential role of invisible cooperation among microbes as core to the idea from Jesus and the Psalms that the least are first in the kingdom of God, and that the kingdom of the world wrongly imagines success against an instinctive assumption that the first are first, whereas in evolution the apex species only retain their peak position when the whole mountain supporting them remains stable. For example algae are at the foundation of the pyramid, and humans will need to make sure algae and soil bacteria etc have a fecund environment to avoid global collapse.

Harry Marks wrote: But I suspect that this version of telos, like Dennett's "adaptation hills" may act sporadically if relentlessly.

I don’t see sporadic as the right word here. Telos requires continuity, as any break in the causal chain punctuates the equilibrium, more as a pin in a balloon than a full stop or comma leading to a continuation of the grammatical idea.

Harry Marks wrote: I was listening to the BBC's "Why Factor" on "Why some people choose childlessness" as I drove around the capital city today. They noted that the ability to choose childlessness if you have a sex drive is relatively new. And I wondered if, in twenty generations or forty, childlessness by choice would be totally bred out of people. I rather suspect not. Not only does the childless person often contribute to the reproductive fitness of relatives, but the variation may continue to arise spontaneously. This is Gould's big obsession - variation is the byword of biology. You might think nothing is as ruthless as chosen childlessness in weeding out its genetic basis, but the genetics of such a trait may be very complex. It might, for example, be strongly associated with intelligence, (the BBC says women who find alternative sources of fulfillment are much more likely to choose to remain childless), in which case some of the people in that category go ahead and have children, with very high reproductive success because intelligent people have good options in the mating game.

Unfortunately, the idea you imply here of selection for intelligence looks wrong, since rich and smart people now tend to have smaller families where they apply more care to each child, while the poor and stupid tend to have more children and rely on the state, through health and welfare systems, to prevent the mortality that in the past reduced child survival. So the overpopulation problem is more about the stupid outbreeding the smart, and then using democracy to increase tax on the rich and wreck the ability to generate wealth, in a trajectory towards collapse. It is a sad fact that only smart people tend to limit their family size out of concern for the planet and in response to the new career opportunities open to women, producing a secular declining trend in human intelligence as an evolutionary response to technology.

Harry Marks wrote: Dennett has succeeded in convincing me that "telos" is a very problematic concept.

Indeed it is. Like salvation, telos is a religious idea with so much metaphysical baggage that it is hard to salvage coherent meaning from the rubble of Christendom. But salvage we must, if we are to answer the basic question if life has any purpose or meaning. I see the movement of gene space to its adaptability frontier as the telos of human evolution, seeing the meaning of life as the good of the future.

Harry Marks wrote: whether it can be said that brains and computers are just hosts co-opted by cultural memes for their own reproduction.

It may be worthwhile to set the causal framework here in Aristotle’s theory of the four causes. https://en.wikipedia.org/wiki/Four_causes says In The Question Concerning Technology, Martin Heidegger explains the four causes as follows:
1. causa materialis is the material or matter
2. causa formalis is the form or shape the material or matter enters
3. causa finalis is the end
4. causa efficiens is the effect that is finished

Robert Tulip wrote: So the gene space of the savannah includes a giraffe with a very long neck nerve, (per Dawkins’ discussion of giraffe evolution).

I'm not particularly familiar with which points Dawkins made about them, but it is an interesting case. To say the potential existed within "proto-giraffes" before the latest speciation is not to say that there were occasional very long-necked individuals in the population of okapis which became giraffes. Rather, as some savant suggested (it may have been Gould where I read it) it seems there is a potential for a population to drift genetically in a particular direction. If you select for very tall individuals, the natural variation that arises in each new generation will create even taller ones in the next generation, and if they are further selected, still taller ones in generations beyond that.

It is a bit strange to refer to such drift as "mutation". Biological populations seem to introduce variation around the mean in a natural, constant process. This probably involves some weakly controlled replication within embryos, so that the number of copies made of some genetic codons may be more, or less, than in the parent genes. Normally more variation is just fodder for the selection process, but under selection pressures strong enough for speciation, it actually generates raw material for powerful innovation.

Robert Tulip wrote:Your point about disastrous variation makes me think of that science fiction story (can’t remember specifics but perhaps Arthur C Clarke) about how as soon as intelligence evolves it goes extinct due to its extreme instability. To me that is a key argument for religion, as the framework of natural order enabling evolutionary survival, to cross the dangerous and difficult evolutionary threshold from instinct to reason and control our selfish genes. That is entirely how I read the Bible.

It is phenomenal how cooperation has gathered such momentum culturally that it does indeed outweigh the pressure of "our selfish genes" (who have, after all, had it easy until culture came along. It used to be no great feat to get animals to procreate, for example.) I suspect religion is going to turn out to be one of the many important tools in the toolbox of culture, and whether it plays a positive role may be a matter of whether reason can have enough influence on it.

Robert Tulip wrote:Putting on your economic hat, I wonder if you think a boundary of adaptation may be analogous to the production-possibility frontier?

I suspect that is a good analogy, but an even better one might be a production function. There have been some pretty effective estimations done of a "nutritional production function" for example, able to detail the tradeoffs between carbohydrates, fibre, fat, protein and sources of particular nutrients including vitamins and calcium. People in impoverished environments manage these trade-offs better than people in rich countries who face very little budget constraint on food. Similarly, biologists have had some success finding tradeoffs between energy expenditure and the gains from added survival or reproduction.

I love the example I saw recently, I think in a museum, about how evolution of a fourth surface on molars had led to radiative evolution in several times and places. Just that little bit of extra efficiency in food use led to new species because new "niches" opened up.

Robert Tulip wrote:Unfortunately, the idea you imply here of selection for intelligence looks wrong, since rich and smart people now tend to have smaller families where they apply more care to each child, while the poor and stupid tend to have more children and rely on the state, through health and welfare systems, to prevent the mortality that in the past reduced child survival.

Actually, there are several forces moving against that pressure. First, people tend to imitate those of higher status. So culture moves the "invest in children's minds" paradigm down from the rich and well-educated to the less advantaged. Second, status tends to confer the advantages I mentioned, in terms of mate selection and group nurturance.

And third, high family size is often a matter more of not understanding the possibilities than of determination to have many children. Not so much failure to understand contraception, though such ignorance is still fairly widespread, or to have access to it, another widespread problem, but failure to see the potential from small advancements in education level and other investment in quality of life. As a result, high reproduction populations tend to be naive, and thus to contain plenty of potential to move into the more investment-oriented mode of culture - so that making the effort to "bring them in" is likely to pay off heavily for mainstream culture. India does not yet appreciate this, but nowhere is it more obvious to outsiders.

Robert Tulip wrote:So the overpopulation problem is more about the stupid outbreeding the smart, and then using democracy to increase tax on the rich and wreck the ability to generate wealth, in a trajectory towards collapse.

I think you would be hard-pressed to show any relation between taxation of the rich and declining ability to generate wealth. The wealthy seem to be resourceful whether they have massive incentives or just some incentives.

In The Ghost in the Machine, Arthur Koestler discusses the Cartesian notion of mind-body dualism, which he says (and I'm paraphrasing here) is an artifact of the human "triune" brain that is built on top of our more primitive brain. Our personal experience of duality arises from what Koestler calls a holon—the notion that the mind is at once a whole and a part, but is in fact a brain warring with itself. Ultimately, Koestler says, the "ghost" we sense in the machinery of our brain is an illusion.

Dennett doesn't discuss Koestler's work, but in this chapter he goes to great lengths to suggest that Gould's long quarrel with adaptionism, gradualism, and extrapolationism are an effort to find skyhooks when skyhooks aren't really necessary. (Or if they are, we haven't found them yet). Though Dennett is pedantic in places—Harry mentions his long dismantling of spandrels—this chapter effectively uses Gould as a jumping off point to argue some of the mechanics of naturalistic philosophy. In a way, he shows much respect and pays homage to Gould. He throws in a great baseball analogy—Tinker to Evers to Chance—and demonstrates an astonishing familiarity with Gould's work as well as with the man. And I think it's very true that Gould had a tendency to overdramatize the importance of his own theories, including punctuated equlibrium. As Spock said, superior minds breed superior ambition. I am more or less open to the idea that Gould was looking for a ghost in the machine, so to speak, at least on a subconscious level, and that he did in fact unintentionally provide lots of wedge room for Creationists. We've actually seen some of that here on Booktalk over the years. There's a sense that new discoveries in evolutionary science are a weakness because they move us well beyond Darwin's original theory. But in fact, the new discoveries only make the theory more robust and dynamic. You will always have those who are uncomfortable with Darwin's dangerous idea. It must be an artifact of our layered brain, although I'm probably hopelessly misusing the concept of "ghost in the machine."

This chapter covers a lot and much of it is over my head. But I'm really starting to see this book as one of the most important books I've ever read. Dennett is adept in explaining the complexities of natural selection and in framing the theory's philosophical impact. I may not comment more as I continue to read at a snail's pace, but I at least wanted to mention that it is an immensely challenging and rewarding book.

geo wrote:Dennett doesn't discuss Koestler's work, but in this chapter he goes to great lengths to suggest that Gould's long quarrel with adaptionism, gradualism, and extrapolationism are an effort to find skyhooks when skyhooks aren't really necessary.

I must have missed the part where he provides any basis for thinking Gould's "quarrel" in fact represents such an effort. I certainly missed the part where he accurately states the basis for the views of the person he disagrees with. It looks very much to me as if Dennett dipped into the controversy thinking he had a ready-made example of skyhooking and ended up baffled by the complexity. So he decided to go with his initial appraisal, which is basically what skyhooks are about: imagining a mechanism where there isn't one, because it connects the dots of appearances.

geo wrote:this chapter effectively uses Gould as a jumping off point to argue some of the mechanics of naturalistic philosophy. In a way, he shows much respect and pays homage to Gould. He throws in a great baseball analogy—Tinker to Evers to Chance—and demonstrates an astonishing familiarity with Gould's work as well as with the man.

In spots, it is true that Dennett shows much respect to Gould. But when your bottom line is disrespect, the respect you show just looks like lip service. In spots, he shows astonishing familiarity with Gould's work. But when he never engages the heart of the work, which is the Mayr's mathematics of speciation and Gould and Eldredge's application of it to the fossil record as punctuated equilibrium, then turns around and disses Gould as some sort of mystical or subconscious searcher for an impossible mechanism serving some wished-for purpose, (all the details of which, in classic skyhook fashion, are left completely vague), one has to wonder why he has any reputation for competence.

geo wrote:I am more or less open to the idea that Gould was looking for a ghost in the machine, so to speak, at least on a subconscious level, and that he did in fact unintentionally provide lots of wedge room for Creationists. We've actually seen some of that here on Booktalk over the years.

One reason Gould has taken such an active role in testifying against creationism (including Intelligent Design) in the science curriculum is that people have tried to twist his research and claim it supports their view. Scientists cannot be held responsible for what weird things others read into their research. Their job is to read the evidence and draw the conclusions the evidence points to. Period. Any wedge room for flat-earthers is irrelevant.

Would we really want to go around telling scientists that they can't entertain certain hypotheses because "Joe Average" might misunderstand and misuse the result? Are we really in the business of telling scientists what they can and cannot think about how the universe works?

I can tell you that such self-censoring goes on among economists, and it is pernicious in the extreme. Without larger forces giving rise to dysfunctional behavior it would not have bad effects on society, but since those larger forces are in operation, the self-censoring has led to noticeable harm. Just two examples are the avoidance of careful examination of trade opening on wages of the unskilled (which, arguably, brought us Trump) and the avoidance of use of straightforward Keynesian modeling in the Great Recession, which Krugman has demonstrated occurred and was foolish.

So here's my question: where is the evidence that Gould was looking for a ghost, or a skyhook, or something other than an algorithmic mechanism? Dennett's only "evidence" is that people have wishfully twisted his ideas, and that Gould has used his ideas to repeatedly question unfounded consensus. Since when is questioning consensus, on the basis of evidence, a sin in science? What is a sin is accusing others of illogical reasoning without backing it up.

geo wrote:There's a sense that new discoveries in evolutionary science are a weakness because they move us well beyond Darwin's original theory. But in fact, the new discoveries only make the theory more robust and dynamic.

Dennett has the grace to acknowledge this fact, though he ungraciously presents it as if it is a counter-argument against people (like Gould) who have made the same argument before him.

geo wrote:I'm really starting to see this book as one of the most important books I've ever read. Dennett is adept in explaining the complexities of natural selection and in framing the theory's philosophical impact.

I wish I could agree with you. I was interested in the later material on artificial intelligence, sociobiology and morality. I thought Dennett did some good work in bringing useful ideas, such as mechanisms that bring an algorithmic process closer to its true successes than random processes would do, in application on these related matters. But in the end his best work was in corralling the interesting work others have done to advance the discussion by tiny bits here and there. Not a waste of time for what is essentially a work of popularization, but nothing like the grand vision we were led to expect.

He left me with the impression that he has a ghostly idea that all of these ideas are related by algorithmicity, and that he is too busy putting fingers in many pies to actually think through the issues that matter to the debates he raises. So he tried to deliver a big reveal by imposing a narrative of "look - a skyhook!" where it had no place, and that is just scurrilous.