I don't have a copy of Daniel Dennett's book, Darwin's Dangerous Idea, I read it from the library, or, rather, I read part of it. I thought he was full of crap and didn't see much reason to finish it. I might be able to find a pirated copy online but I don't really feel like finding it. I'll rely on this description of his thesis from the review of the book by the prominent evolutionary geneticist, H. Allen Orr* because it confirms my thesis in this post
Dennett's thesis is simple enough. He is convinced that intellectuals underestimate the explanatory power of evolutionary theory, which to Dennett means natural selection. He is sure that natural selection is both more potent within biology than many biologists believe and more relevant to problems outside biology than many social scientists and philosophers pretend. In an analogy that runs through the book, Dennett likens Darwinism to a "universal acid," an allusion to childhood lore about an acid so corrosive that it eats through everything -- including the jar in which you desperately try to contain it. According to Dennett, the universal acid of natural selection can spread both downward from biology, explaining the origins of the universe and life, and upward from biology, overturning our views of consciousness, cultural change, and the origin of morality. The resulting Darwinian Science of Everything "eats through just about every concept, and leaves in its wake a revolutionized world-view." Dennett takes this Science of Everything idea very seriously: "The idea of evolution by natural selection unifies the realm of life, meaning and purpose with the realm of space and time, cause and effect, mechanism and physical law."
The head of his review contains a quote from Darwin's foremost German disciple, friend and colleague, Ernst Haeckel which is a sorter and stronger statement of the same claim.
Evolution is the magic word by which we shall solve all of the riddles that surround us.
The problem was and still is that that claimed status for natural selection, which is what Haeckel meant when he said "evolution" in that the more I read about the theory, which has changed continually and drastically and which seems to have different meanings to even its scientific adherents - sometimes drastically different - is more than a wished for universal explanation but which only seems that if you want it to be so. If you want natural selection to explain something you make up a story either about something you can observe or, more often, something you cannot and never will be able to observe in the lost past.
This passage from H. Allen Orr's 1996 review of Dennett's dumb book is a good explanation as to why Dennett clearly didn't know what he was talking about in his assertions.
This substrate neutrality argument is supremely important to Dennett. It -- and nothing else -- explains why selection can be lifted from its historical base in biology. It is what makes Darwinism so dangerous. But Dennett slips here. While it is true that many different kinds of substrate can be selected, it is simply not true that Darwinism works with any substrate, no matter what. Indeed Darwinism can't even explain old-fashioned biological evolution if the hereditary substrate doesn't behave just right. Evolution would quickly grind to a halt, for instance, if inheritance were blending, not particulate. With blending inheritance, the genetic material from two parents seamlessly blends together like different colored paints. With particulate Mendelian inheritance, genes from Mom and Dad remain forever distinct in Junior. This substrate problem was so acute that turn-of-the-century biologists -- all fans of blending inheritance -- concluded that Darwinism just can't work. Modern evolutionary genetics was born in 1930 when Sir Ronald Fisher cracked this problem: Population genetics shows that particulate Mendelian inheritance saves the day. It is just the kind of substrate needed for evolution by natural selection to work.
That assertion is a logically coherent observation growing out of the neo-Darwinian orthodoxy that he talked about. There are two big problems for the theory of natural selection in it, one from before Fisher and one after Orr's review was written. The first one is that Charles Darwin and his named, approved disciples who promoted his natural selection believed in the inheritance of acquired characteristics. As his foremost scientific promoter in Europe, Ernst Haeckel put it in 1899,
The immense significance of this positive knowledge of the origin of man from some Primate does not require to be enforced. Its bearing upon the highest questions of philosophy cannot be exaggerated. Among modern philosophers no one has perceived this more deeply than Herbert Spencer. He is one of those older thinkers who before Darwin were convinced that the theory of development is the only way to solve the enigma of the world. Spencer is also the champion of those evolutionists who lay the greatest weight upon progressive heredity, or the much combated heredity of acquired characters. From the first he has severely attacked and criticised the theories of Weismann, who denies this most important factor of phylogeny, and would explain the whole of transformism by the c all-sufficiency of selection. In England the theories of Weismann were received with enthusiastic acclamation, much more so than on the Continent, and they were called “Neo-Darwinism” in opposition to the older conception of Evolution, or “Neo-Lamarckism.”
Neither of those expressions is correct. Darwin himself was convinced of the fundamental importance of progressive heredity quite as much as his great predecessor Lamarck; as were also Huxley and Spencer.
Three times I had the good fortune to visit Darwin at Down, and on each occasion we discussed this fundamental question in complete harmony. I agree with Spencer in the conviction that progressive heredity is an indispensable factor in every true monistic theory of Evolution, and that it is one of its most important elements. If one denies with Weismann the heredity of acquired characters, then it becomes necessary to have recourse to purely mystical qualities of germ-plasm. I am of the opinion of Spencer, that in that case it would be better to accept a mysterious creation of all the various species as described in the Mosaic account.
It is clear that when someone talks about "Darwinism" of "natural selection" if they don't include Lamarckian inheritance of characteristics acquired apart from the particulate inheritance from genes, they aren't talking about "Darwinism" they aren't talking about the same thing he, Haeckel, and the founding generation of Darwinists meant by "natural selection." "Natural selection" as my generation and probably all living ones were taught it, was not "Darwinism" because of that. Darwinism isn't one thing, it seems to mean whatever whoever uses the term means, "natural selection" is no more uniform in its meaning as I found when I asked a half-dozen professional biologists to define it. One included genetic drift in their definition, to tell you how muddy the word is.
And, as Orr points out, if your understanding of "natural selection" is the post Fisher conception my generation was taught, that Mendelian genetics "disproved Lamarck" that extra-genetic traits were heritable, natural selection doesn't really explain things.
The problem is that in the decades after Orr wrote that, the reality of epigenetic inheritance has been demonstrated far more strongly than I believe natural selection ever was. If someone wants to point to me what just-so story of natural selection has the same kind of robust definition and evidenced proof, I'd love to read it. Don't bother with the black and speckled moth story, that one doesn't really work. Things are clearly a lot bigger than any one explanation that anyone has invented can cover.
I think natural selection is almost always asserted through circular, self-confirming assertion when it isn't a matter of classical logical fallacy, begging the question in which natural selection is asserted as part of the question that is, then, unsurprisingly confirmed. I think politically, within biology and outside of it, especially in the popular culture of the college-credentialed, it is an orthodox, required framing for thinking or articulating anything to do with the fact of evolution. Evolution is a fact without any overarching explanation. In the absence of that overarching explanation the temptation of coming up with a just-so story among the hardest of hard boiled scientists and forcing compliance with it has proven to be an irresistible urge to those who find natural selection congenial with their personal and professional interests and preferences.
There was a time when I would have been surprised by it, though I am not now, that scientists turn out to be really rather amateurish at practicing philosophy. It's a sign of how strong the conventional atheist interest in Darwinism is that a professional philosopher of Dennett's standing turns out to be as foolish about Darwinism as his biologist atheist-materialist buddies, Dennett is a huge wannabee, hankering after the same misplaced repute that they have as scientists, using the vehicle of Charles Darwin's inadequate theory to get it for him.
Dennett is small beer, his true measure being nobody in philosophy takes him seriously. He said he'd explained consciousness; nobody noticed.
ReplyDeleteI have a new book by a French philosopher who attacks the idea of certainty that Dennett and armchair philosophers like Dawkins rely on. He argues in favor of a concept of "negative certainty." Its an argument in favor of ambiguity, as best I understand it, because (in simplest terms), the more you know, the more you know you don't know. The fool, in fact, is certain of his knowledge.