Fodor's fight against fitness
By Mark Vernon on Monday, February 8 2010, 06:31 - Science - Permalink
The storm is brewing around What Darwin Got Wrong, Jerry Fodor and Massimo Piattelli-Palmarini's essay debunking neo-Darwinism. It pulls no punches and has already made enemies. Which is a shame. So far, I've only found two responses that weren't mostly ad hominen counterattacks. (That's religiosity for you.) The first broadly agreed. The second didn't actually refute the argument. It merely said neo-Darwinism can embrace Fodor's critique - though as Mary Midgley nicely remarks in her review, that extension is done at the cost of adding epicycles.
Fodor's argument, in short, is that whilst there is certainly evolution in nature, there is no coherent theory of evolution by natural selection in science. The theory doesn't add up because it can't shed its intentionality: natural selection must always be selection for something, but only minds can select for, and nature doesn't have mind. That's the reduced version of the logical refutation. Then there's the mounting evidence that all kinds of processes are involved in the evolution of species, and that natural selection, even if it could be coherently formulated, would be just one amongst very many, and possibly not a very important one at that. Hence, Fodor concludes that evolution is like history. There are no laws, beyond the constraints imposed by the physical world itself. Evolution is just one damn thing after another.
I'd be interested in serious engagements with the book. So do leave links if you find any. But since it inevitably plays into the politics of evolution, it's interesting to ask who are the winners and losers if their argument is right.
Evolutionary psychology is the big loser. If evolution is not shaped by biological laws, then there's no universal adaptionism, which means that evolutionary psychology's accounts of how friendship, disgust, religion and so on got going are as Stephen Jay Gould always said they were: just so stories. There just isn't the evidence to piece together a prehistoric genealogy of these things, and it's hardly likely there ever will be. Evolutionary theory's 'universal acid', as Dennett put it, is neutralized in the slime if Fodor is right.
The book's a challenge to religious believers too. For those who don't accept evolution, the end of the theory does not mean the end of the processes of evolution. It still happens, just piecemeal. The natural world is not designed, and it never was. Fodor cites Gould again when he said that if you ran the tape of evolution twice, everything would turn out different. That's a result of there being no laws once more.
For those who accept evolution, and say that it's just God's way of shaping the natural world, the end of neo-Darwinism will be tricky too. If things could have turned out differently, then there's no necessity in evolution, which implies that humanity, say, might not have been. That somewhat scuppers divine purposefulness in creation: God is forced to play dice, as it were.
That said, the work of individuals like Simon Conway Morris, a 'wet' biologist who spots repeated convergences in evolution, is not really discussed by Fodor. Convergences imply that evolution 'seeks out' solutions to ecological problems, something Fodor strongly denies. If convergences follow multiple and different evolutionary paths - and it doesn't matter whether by natural selection or not - that would seem to be a problem for him.
The big winner is evolution itself. It'd become a subject that never ends, like history. They'll always be variations in the way the past can be reconstructed, always new details to add, always unseen factors at play. In her review, Midgley says Darwin would have welcomed that. Whatever the story of terrestrial evolution turns out to be, the story of evolutionary science now looks radically incomplete.
UPDATE Michael Ruse, whose even-handed views on matters Darwinian I value, has reviewed the book in the Boston Globe and he finds the book 'intensely irritating' and 'very odd'. That said, I imagine that Ruse's review will irritate some neo-Darwinians too. 'The Darwinian is using a metaphor to understand the material nonthinking world,' he writes. 'We treat that world as if it were an object of design, because doing so is tremendously valuable heuristically. And the use of metaphor is a commonplace in science.'
Comments
Thanks for this post, and I also recommend Mary M's review article.
The risk for Fodor is that he overstates the 'lawlessness' of the evolutionary process he argues for (and I think his critique has a lot to be said for it). Mark is right to mention Simon Conway Morris here. Morris argues compellingly that ecological variables and physiological constraints combine to produce much the same 'solutions' in nature over and over again, and presumably would also do so elsewhere in the cosmos. The 'laws' move from the level of selection to the level of initial conditions and development of systems.
Hmm, if that really is Jerry's argument, then I have to disagree.
"The theory doesn't add up because it can't shed its intentionality: natural selection must always be selection FOR something, but only minds can select for, and nature doesn't have mind."
Each selection is simple and if there is no mind involved it is just a scientific balance of probabilities. In the longer run, it may appear to have been "for" something, if the accumulated changes have selected for or agiants some larger pattern or species. But that appearance is the intentional explanation, not any intention in the individual events. As soon as there are agents with minds involved ... there is intention and psychology too. Though again what those minds were selecting for in each decision may have nothing to do with what ensd up being selected "for" in the longer run outcomes - which are just more explanations from an intentional stance after the event.
ALSO - "Fodor cites Gould again when he said that if you ran the tape of evolution twice, everything would turn out different. That's a result of there being no laws once more."
Not so. Of course the results would be very different at the species level, but the laws would be unchanged. The laws are about HOW the processes work, not about goals and ends, including the psychological processes.
Be interesting to read. Mary M is usually very thoughtful too.
Fodor's argument is of course more sophisticated than the reduced version I've given above. It's summarised more extensively in the New Scientist: http://www.newscientist.com/article...
The significance of 'selection for' follows by extending Gould's famous spandrels and arches argument. The key paragraph in the New Scientist piece is:
'Darwinists say that evolution is explained by the selection of phenotypic traits by environmental filters. But the effects of endogenous structure can wreak havoc with this theory. Consider the following case: traits t1 and t2 are endogenously linked in such a way that if a creature has one, it has both. Now the core of natural selection is the claim that phenotypic traits are selected for their adaptivity, that is, for their effect on fitness. But it is perfectly possible that one of two linked traits is adaptive but the other isn't; having one of them affects fitness but having the other one doesn't. So one is selected for and the other "free-rides" on it.'
Say it's t1 that's adaptive. That's confirmed, and according to Fodor can only be confirmed, by counterfactuals - namely arguing that if t1 hadn't been selected for then t2 wouldn't be a phenotypic trait either. But the theory of natural selection can't do that because resorting to counterfactuals implies minds.
Similarly in the arches and spandrels case, Gould assumed that the arches were selected for, because that's what architects (with minds) would do. Hence in their book, Fodor concludes, 'A theory of evolution must be able to distinguish the causal powers of coextensive traits; and (as far as we know) the causal powers of coextensive traits can be distinguished only by appealing to distinctions among counterfactuals.'
Related to that:
http://scienceblogs.com/omnibrain/2...
See full text of Fodor's article on pdf at the end of the page.
Thanks for that, though they seem to be referring to old papers, and presumably Fodor has taken account of what Dennett argued in the new book.
Been arguing against conceptions of evolution that consist solely of natural selection and mutation for 11 years now, ever since reading Margulis. Doing so rapidly convinced me that neo-Darwinists can be as fanatical as their opponents. ;)
Thanks for the Midgley link!
Actually, I would tend to disagree with much of what you've said. For example, I fail to see how evolutionary psychology loses or is diminished in any way; nor do I see a loss of universal adaption-ism. Also, the suggestion that things may turn out differently if we were to run the tape measure twice, does not indicate that there is no necessity in evolution, or that laws do not exist, only that events will not duplicate exactly. And the loss of humanity, in the second go round, certainly does not scupper my (perhaps misguided) concept of divine purposefulness.
The problem with natural selection (as I'm sure any microbiologist involved with such research can tell you) is that it really doesn't add up. There really is no "coherent theory of evolution by natural selection"; there really are all kinds of "processes" and natural selection really is just one amongst many, and, realistically, not a very important one at that. And yes, although I do agree that the mind does naturally select (and, in fact, this may be natural selection's only appropriate application) I yet question the semantics here because it is quite obvious that decision making occurs on the sub cellular level. And I think this goes to the very heart of one's definition of such things as "intelligence."
The problem with natural selection is that it directs the mind and in the process unintentionally constrains creativity. The result is a loss of the limitless possibility on which the mind thrives. And, in which our science is born. But, you know, I'm going to read this book because this is a point I have argued for several years (almost heretic-ally it seems), but if your synopsis is accurate, I would tend to agree with you to some extent for I see points of both affirmation and dissent.
Hello. I'd like to present a dissenting view. I should say that I haven't read the book, I've just read the NS article and an older article by Fodor in the London Review of Books, with responses and counter-responses:
http://www.lrb.co.uk/v29/n20/jerry-...
The main problem is that Fodor is attacking a long series of straw men. On the "logical" refutation, he's taken the term "selection" too literally, and this has led him to misunderstand what evolutionary theorists mean by natural selection.
The basic principle of evolutionary theory can be best stated without using the word "selection" at all. It's something like this: the adaptation of species to their environment is due to the differential reproductive success of organisms based on traits which are inherited with variation from predecessors. The successful reproducer will pass on the inherited traits which contributed to that success, so such traits will tend to become more common and/or pronounced in the species over time.
"Natural selection" is a convenient term to describe this principle. But it's figurative. There is no person or thing doing the selecting, and no selection criterion. Contrary to your assertion above, Mark, selection doesn't have to be _for_ something, because there isn't really any selection in the literal sense. So the logical problem stated by Fodor doesn't arise.
You may then say that it's not really a theory of natural selection at all. Well, feel free to come up with another name for the basic principle if you like. "Differential reproductive success" might do, but it doesn't exactly flow off the tongue. Anyway, whatever you call it, it's the principle that matters. And the principle above does explain evolutionary adaptation.
Moving on, you write:
"Then there's the mounting evidence that all kinds of processes are involved in the evolution of species, and that natural selection, even if it could be coherently formulated, would be just one amongst very many, and possibly not a very important one at that."
There's confusion here because natural selection is not a process. Natural selection is just one element in the process of evolution. But it's a central element. It's the only known explanation for evolutionary adaptation. Now certainly not all evolution is adaptive. No-one claims that it is. The idea of "neutral" evolution is fully accepted. But adaptive evolution is particularly interesting because it's what leads to functional complexity.
Besides natural selection, the other element of adaptive evolution is inheritance with variation. And that's where genetic and other constraints come into play. Inheritance with variation is affected by all sorts of factors. But these aren't alternative processes. They are part of the same process. They work _with_ natural selection, providing the raw material for it to select from.
It helps to think in terms of two different things that need explaining. The fact that adaptive evolution occurs at all is explained (primarily) by natural selection. The specific course that evolution has followed is explained by all sorts of causal factors, including genetic constraints. No one denies that the causal factors mentioned by Fodor have an influence on evolution. It's perfectly obvious that, if a particular variation is physically, chemically or genetically impossible, then it won't evolve. Only a fool would deny that, and evolutionary biologists are not the fools that Fodor seems to think they are.
Fodor's other objections similarly turn out to be attacks on straw men. For example, free-riding of one trait on the back of another is a standard part of evolutionary theory. Perhaps biologists understate its frequency, but if he were making that sort of quantitative claim, Fodor would have to do more work to show it. Instead, he makes such absolute pronouncements as the following:
"We should stress that every such case (and we argue in our book that free-riding is ubiquitous) is a counter-example to natural selection. Free-riding shows that the general claim that phenotypic traits are selected for their effects on fitness isn't true. The most that natural selection can actually claim is that some phenotypic traits are selected for their effects on fitness; the rest are selected for... well, some other reason entirely, or perhaps for no reason at all."
No, free-riding is not a counter-example to natural selection, because natural selection doesn't claim that all phenotypic traits were selected for.
The one place where I have some agreement with Fodor is in his rejection of Dennett's idea of natural selection as a "universal acid". Natural selection is central to biological evolution (including the evolutionary origins of psychology) and it's a valuable model for computerised evolutionary algorithms. But so far I remain to be convinced that it has much relevance to other fields.
Hmm.. nice post. But again I would tend to disagree somewhat. You suggest that natural selection is not a process but an element - a central element in the process of evolution. How so? You mean as central to our theory of evolution? Is discovering the elements of evolution not a process? Process, element, element of - all just semantics. And you are simply restating Natural Selection all over again.
You suggest that there is no person or thing doing the selecting and that is simply not true. This should be obvious even to a child or anyone who takes time to observe the natural world. And it something that can be very easily demonstrated.
You prefer the phrase "differential reproductive process" and I understand what you're saying, and I agree that our concern on the evolutionary level is one of species and not one of individual. But inheritance is not the only answer. How foolish could we have been to even consider that it was? Do you really believe that generational adaptation is sufficient?
Has it ever occurred to you that on the molecular level that there is no concern for adaptation at all? That our "evolution" has no concern whatsoever for the survival of the cell, let alone the species? It appears to me that this is simply a creative process (or rather something we would describe as "creative"); if there are any molecular biological laws to be observed or discovered here, any direction to be discerned, it is one of creating anew. It's purposeful adaptation, possibly en masse, and it's "creation."
So, let me ask you, do the molecular biologists agree with you? Because personally I think our molecular biology and our genetics need to agree with our "Evolution." Or one or the other is simply false.
This is why I believe that Natural Selection is far too limiting. It harnesses the mind and directs focus unwittingly onto avenues that ultimately will take us nowhere. It hinders us...
Perhaps brilliant, at the very least thought provoking, in his time and ours - but Darwin is dead and it's time to leave this ghost behind and set our science free.
@betuadollar
"You suggest that there is no person or thing doing the selecting and that is simply not true. This should be obvious even to a child or anyone who takes time to observe the natural world. And it something that can be very easily demonstrated."
I don't understand what you mean. Are you saying there is some intelligence (God?) doing the selecting? Or are you just saying that there are natural forces which cause some individuals to reproduce better than others? The latter is what I'm saying. If that's what you mean then I suppose you could say that "nature" is the "thing" doing the selecting. Is that what you mean? If not, what do you think is the thing doing the selecting?
I am saying that on the cellular level that there are other processes at work here, for example, apoptosis. These processes can be interpreted, and indeed must ultimately be interpreted, as "decision making." And you're right, this goes to the very heart of our definition of intelligence. Intelligence is a rather vague term that we apply in a variety of ways (a common deficiency of language) but reduce it philosophically and what we are left with is not cognitive ability but rather rational ability, or rationality. I think it could be very easily argued that there is as much intelligence contained within just one apple seed as there is within the entire mass mind of all humanity. Of course, the word intelligence takes on at least one other significant meaning, too, not applicable here.
I am not saying that random mutation does not occur or that beneficial genes are not inherited, they are. I am saying that it appears there are any number of things going on which are every bit as significant, if not more so, than natural selection. What angers me in particular is that the very people who have such immediate access to our science (academia) still fear to let these old behemoths go. If Natural Selection is to be the "central element" of our Evolution, then our Evolution is false. You have to bear in mind that our theory, or as they prefer to say, "fact" of evolution is but philosophical exploration. Its the mind's attempt at explanation, very good, since it directs our science, and yet science now appears to have outgrown us.
"God" or "nature" - decisive, and today, divisive terms, or in this case - labels - are we not speaking of the same thing? It is this very question that we are addressing here with our science. I suppose you could say, that in this sense our religion is but the science of yesteryear, or that in its attempts to address the "big questions" that our science is the religion of today. But yet this is not true because our science of today is but an extension of a continuous, contiguous attempt over tens of thousands of years to observe and discern. I would rather not debate "God" here... but suffice to say that there is nothing that exists in the so called natural world without "biological" reason and this includes our religion.
Incidentally, "evolutionary psychology" is a very poor term. I don't know... but perhaps you should see Howard Bloom on this one (?)
To repeat, natural selection is central to evolutionary theory because it's the explanation for adaptation, and adaptation is the explanation for functional complexity.
Imagine that there was no natural selection. Imagine that some god intervened to ensure that all individuals had equal reproductive success regardless of their innate characteristics. There would be no adapative evolution and no functional complexity.
Sure, there are lots of other things going on that explain the particular path that evolution has followed. But they don't explain why organisms are well-adapted and have functional complexity.
P.S. If you have some other explanation for the well-adaptedness of organisms (Lamarckism perhaps) please let us know what it is.
Personally, natural selection is a phrase I would prefer to avoid because I view it as a far too simplistic explanation and wholly inadequate.
"Imagine that some god intervened to ensure that all individuals had equal reproductive success regardless of their innate characteristics. There would be no adaptive evolution and no functional complexity."
Ok, you're right, let's imagine... let's imagine, say, that individuals (human beings, for example) do have equal reproductive success (well, because they do)... Do you see where I'm going with this? And no, I don't fully buy the theory of generational population genetics as the end-all. And, there are also a number of other contributing factors in terms of the survivability of a particular species. And, there are also new possibilities we must consider.
Both Natural Selection and natural selection need to be reduced to but a paragraph or two both in our textbooks and in our theory because, quite frankly, there is so much more.
Since you won't address my argument, I have nothing more to add.
@Richard Wein Just a busy few days... But, in short, Fodor says that adaption is itself an illusion: the 'niche' into which organisms are apparently adapted is actually itself created by the functional complexity (beyond the physical constraints within which organisms must, of course, work). There are no series of unexploited niches in the natural world waiting, as it were, for an organism to arrive. So the problem of design doesn't arise for him. It's simply a case of what works, and what works well enough. Something like that anyway...
@Mark. Hello. Thanks for taking the time to reply, though you haven't actually addressed anything that I wrote. Do you deny that organisms are well-adapted to the conditions they find themselves in? If you don't deny it, then how do you explain that well-adaptedness?
P.S. Mark, you wrote: "But, in short, Fodor says that adaption is itself an illusion: the 'niche' into which organisms are apparently adapted is actually itself created by the functional complexity (beyond the physical constraints within which organisms must, of course, work)."
Adaptation is not to a niche. A species merely adapts to its CURRENT conditions, whatever they happen to be. It seems that once again Fodor has misunderstood evolutionary theory and misrepresented it. He has thoroughly misled you.
"It's simply a case of what works, and what works well enough."
Yes, that's what evolutionary theory says. Here Fodor is simply stating standard evolutionary theory, not contradicting it.
P.S. I just saw your update. I can't see anything in Ruse's article that would irritate a "neo-Darwinian". The use of design as a metaphor is competely standard.
Richard Wein,
Since you asked, there are serious problems to the notion of biological adaptation (which you seem to take as a given.)
1. First, it's very difficult to show non-adaptation except by tautology. If an organism were ill-suited to its current conditions, how would we know? To say it would suffer differentially in reproductive ability just affirms the consequent. Maynard-Smith wrote that we could nullify adaptationism if we could find traits whose lack of survival value was obvious, for example, patterns of stellar constellations on a frogs's back. Waddington replied that we could postulate survival value for almost any trait (forgive me, I've forgotten his examples). Conversely, what are we to make of the fully developed lungs of the hellbender fish, which respirates entirely through its skin, or the functioning prostate of the female Guinea Multimammate Mouse? I don't imply that exceptions to adaptation disprove the principle, I merely ask on what grounds we make a determination of an organism as adapted that is not tautologically linked to differential survival?
2. Even if we could not come up with explanations, Orgel's rule is always there to keep a portion of neo-Darwinism safe in a black box. If "evolution is smarter than you are," (as I tend to believe it is) then falsification of adaptation becomes a logical impossibility.
3. Adaptation is explicitly anthropomorphic. We are not tempted to say that mountains adapt to gravity by eroding, or that water adapts to cold by freezing. But in the case of "life," we are reluctant to resort to any explanations that don't invoke mind and intention, at least metaphorically. And yet mountains and planets and organisms are all part of a single, naturalistic universe. If we can discuss "inanimate" nature without using metaphors of mind, it is at least grounds for suspicion that we have so much trouble doing the same with living forms. There is an embedded dualism in this aspect of evolutionary thinking, that goes back to the vitalistic thinkers of the 19th century that gave it its name.
You write that "natural selection is just figurative" because no one is doing any actual selecting, but if we apply the same logic, no one is doing any adapting either. Adaptation is the appearance, in the same sense that the sun appears to rise and set. It has no meaningful scientific value.
I do wish people would read what I've said and address it, instead of going off on a tangent. Chris, you're confusing adaptation with adaptationism (en.wikipedia.org/wiki/Adaptationism). I haven't said anything adaptationist. In evolutionary theory "adaptation" just means "becoming better suited to ones environment".
To get to the crux of the matter, let me ask you the same questions I asked Mark. Do you deny that organisms are generally well-adapted to their environment? If you don't deny it, then how do you explain that well-adaptedness? (If you have a problem with the word "well-adapted" try substituting "well-suited".)
P.S. Wikipedia defines adaptation as follows: "Adaptation is the evolutionary process whereby a population becomes better suited to its habitat" (en.wikipedia.org/wiki/Adaptation). It cites The Oxford Dictionary of Science as giving the following definition: "Any change in the structure or functioning of an organism that makes it better suited to its environment". I hope that's authoritative enough for you.
Richard,
Logically, if we're going to establish a fact of adaptation in biology, we are going to have to be a little bit adaptationist in our thinking, at least here and there. I therefore don't see such a big firewall between the two. If we can't see specific adaptations we have no data to generalize from, quite apart from the question of whether our generalizations should take other facts into consideration (neutral theory, evo-devo).
Answering your question specifically, I would say that "deny" is a strong word, but I think that the appearance of adaptation is deceiving for the reasons I gave above. What would a non-adapted organism look like? What are our criteria for calling an organism fit or unfit?
Whenever it is pointed out that some organisms seem to be insufficiently adapted to their environments (we can always imagine improvements in design), the answer is that nature provides only what she needs, and no more. When it is pointed out that some organisms appear overly adapted (giraffe, peacock) the answer is that evolution is smarter than you are. This suggestions a concept that lacks precision.
In order to know if an organism is "better suited" to its environment, we need to examine its differential survival compared to the wild type. (There being no such thing as instrinsic fitness without context). In turn, in order to explain why mutants differentially survive compared the wild type, we say they are better suited. This is an obvious circularity. If we could give a definition of one that didn't invoke the other, I'd grant that adaptation might have some semantic traction.
I believe in evolution wholeheartedly. The evidence, both archaeological and genetic, is overwhelming, and alternatives like divine creation are preposterous from the start. But the concepts of adaptedness and design have been leading us away from good science for two centuries and it's time we let them go.
Hi Chris. You've raised several issues that don't refer to anything I've written. I didn't say anything about how we might know whether something is an adaptation. I'm talking about how evolution works, not how we can know it. I didn't say anything about "insufficiently adapted" or "overly adapted". I agree these concepts make no sense in the context of evolutionary theory. I didn't give the circular explanation that you described, and no evolutionary theorist should give it either.
>In order to know if an organism is "better suited" to its environment, we need to examine its differential survival compared to the wild type. (There being no such thing as instrinsic fitness without context). In turn, in order to explain why mutants differentially survive compared the wild type, we say they are better suited. This is an obvious circularity. If we could give a definition of one that didn't invoke the other, I'd grant that adaptation might have some semantic traction.<
To explain why some individuals tend to survive better than others, you have to look at specific cases, e.g. white polar bears survive better than brown ones because they're better camouflaged. There is no general reason. It's like asking why some people run faster than others. There are all sorts of reasons why one person might run faster than another. There is no general reason.
I would say that the best definition of "better suited to its environment" probably is "having greater reproductive success in that environment", though I'm not certain. When I say that a cheetah (for example) is well suited to its environment, I suppose I mean that it has features that give it higher reproductive success than a hypothetical cheetah in the same environment that doesn't have those features. For example, a normal cheetah would have greater reproductive success than one with no eyes or inferior eyes. We could also say that its eyes are well suited for seeing.
I still haven't seen a valid reason why we should drop the term "adaptation" from evolutionary explanations.
Richard,
I would have perhaps addressed your argument if I had conceived of an argument; I apologize.
I have no problem with the definition of adaptation as provided by Wikipedia, although, again, I do question such a blanket theory as stated there, and in fact, have questioned it since childhood. Simply because, to the simplistic mind of a child, it makes no sense. To a child only observation can serve as truth and that which he or she observes does not appear to support such a theory: many amongst us appear less than well-suited, or well-adapted, and yet still appear to have very little difficulty surviving long enough to quite readily reproduce. If our species is to be wholly dependent upon generational adaptation then we are doomed simply because it does not appear that we will adapt readily enough. And this, I will remind you, is from the mind of a child. And yet to this day, I still believe, that our science, if nothing else, needs make sense.
Well-suited is a rather relative term, again if we were to consider human beings - and why not since we are human beings and conduct ourselves solely for human beings - there is no archaic form available that might allow us to be so discerning, or to say, for example, that we are now well or better suited. Perhaps our ancestors were better suited or better adapted. Are we then but an evolutionary, selective, anomaly?
The problem with Natural Selection, as currently presented, is that it in essence serves to repress the minds of those who might otherwise creatively explore. Perhaps it is better viewed as a sounding board, as something to bounce ideas off of, or use when it suits us. But it matters not, science is not focused or concerned with "adaptation" - its concern is not with the "why" but the with the "how."
I do agree with Fodor that adaptation itself is but an illusion and I do believe in this thing of "niche" and I do believe that Evolution is far smarter than we are, essentially capable of virtually anything.
You ask who, or what, I think is doing the selecting and perhaps this is where the "argument" lies... Well, that, I believe, is exactly what science is attempting to answer. And although the scientist certainly has a place in this debate of Evolution versus GOD, science itself certainly does not. Suffice to say, time and space here simply do not allow, but the very briefest version is this: if we are to adopt Evolution as our paradigm, and I believe we must, then we must look beyond the merely anatomical to fully embrace the concept that ALL within the human mind is the product of evolutionary desire... talk about "circularity." And if Evolutionary theorists should somehow fail to recognize this, again, I would refer them to the child.
D. Davis... Manorville, NY
I've penned my own response to Fodor and Piattelli-Palmarini's New Scientist article here:
http://mccabism.blogspot.com/2010/0...
I've been thinking some more about this, and I've realised that adaptation shouldn't be defined in terms of reproductive success after all. (I had my doubts.) Before offering a better definition, I'll give a specific example. Suppose we have a mixed population of brown and white bears living in a snow-covered environment, the colour being a heritable trait. Suppose that the white bears survive and reproduce better than the brown because they are better camouflaged against the snow, so the proportion of white bears increases over time. Then it seems reasonable to say that the population is adapting to its environment.
Why does this seem reasonable? It's because the population is becoming better at being camouflaged in the white environment. More generally, the population is acquiring a functional trait. It's the existence of such functional traits that needs explaining. People don't ask "how did organisms get to have such reproductive success?". They ask "how did organisms get to have such functional traits as camouflaged fur and eyes?".
So I would now define adaptation of a population (to an environment) as the development and spreading of traits that are functional (in that environment). The white colour of fur in the example above is for camouflage (i.e. has the function of camouflage). Similarly, eyes are for seeing. The ultimate effect of having eyes is to enhance reproductive success, and that's relevant to why we consider eyes to be functional, but we don't say that eyes are for reproducing.
This brings us back to the issue of "selection for", which Mark raised at the start of the thread, and I think I was too quick to dismiss it. We may not need to use the expression "selection for", but the idea of a trait being "for" something (i.e. having a function) is important. The subject was covered well by Dennett in "Darwin's Dangerous Idea", and I'm not going to elaborate on it here, except to deny the assertion that it requires a mind. What's wrong with saying that eyes are for seeing, even if they weren't the product of a mind?
An even more scathing review of the book, this time by philosophers Ned Block and Philip Kitcher:
http://bostonreview.net/BR35.2/bloc...
They concentrate almost entirely on what appears to be F&P-P's central argument, and it turns out to be an argument that Mark and Mary Midgely didn't mention at all. Perhaps it was too weird for them to get to grips with, so they passed quickly on to more familiar complaints. If Block and Kitcher's account of F&P-P's argument is to be believed--and it seems credible to me--the entire argument is based on a fallacy of equivocation.