The second chapter of Dawkins' The Selfish Gene gives us an eagle-eye view of the subject matter, and a genealogical speculation. My procedure will be the same as the first post: first a look at his basic thesis, and then a philosophical critique.
Dawkins makes a very important point early in the chapter that Darwin’s notion of “survival of the fittest” is “really a special case of a more general law of survival of the stable” (13). This is surely right, and as Evelyn Fox-Keller has pointed out (in her excellent Century of the Gene), species stability is the real hot topic in genetics and other biological sciences these days. In other words, the real question is not “how do things change” but how, given change, what conditions make it possible for a thing to stay the same – or similar – in other words, to survive. For Dawkins, the history of this emergence of stability can be written in terms of Darwinian natural selection from its earliest conception, that primeval soup after the big bang.
To justify this, Dawkins appeals to the idea of molecule stability. Molecules, like hemoglobin, are extraordinarily stable, and if you have a stable molecule (because of its structure), it “will tend to stay that way. The earliest form of natural selection was simply a selection of stable forms and a rejection of unstable ones” (14). So, the basic Darwinian concept of natural selection – which, in Darwin, starts mid-stream, in already complex forms of life – for Dawkins can at least be understood in even the earliest forms of life.
I really do wonder what other biologists make of this argument, and Dawkins doesn’t present much evidence beyond this logical construct. Because stability is the goal (Dawkins uses this type of language), things that are more stable tend to stick around, as opposed to less stable stuff. This of course doesn’t account for the complexity of humans, but this complexity is “where Darwin’s theory, in its most general form, comes to the rescue. Darwin’s theory takes over from where the story of the slow building up of molecules leaves off” (15).
And so Dawkins takes on a “necessarily speculative” journey, with the caveat that “the simplified account I shall give is probably not too far from the truth” (15). The beginning of this story is standard. The primeval chemical soup leads to the building blocks of life, and this means molecules. The innovation (I think – Dawkins cites absolutely no one, so it’s really hard to know, as a science outsider, if this is a common view, or who first thought of it. I find this annoying.) comes in the idea of “replicator.”
Now the concept of “replicator,” and indeed the concept of unit of selection, apparently has been debated quite a bit in the scientific literature. I found a few articles describing this debate (see Samir Okasha on this), and it seems that Dawkins doesn’t really take into account other views, like Hull’s replicator/interactor distinction, or Lewontin’s criticism. But in any case, he presents replicators as having essentially two functions: they re-create the structure of the molecule they copy; and transmit the differences or variations (‘errors,’ in Dawkins-talk) to the next generation.
Dawkins’ replicators have three characteristics: (a) longevity (selected for); (b) fecundity (the rate of production); (c) accuracy (18-19). Finally, these three aspects will be selected for in competition. Those molecules that show the least of these attributes will not survival; those that show the most, will (although Dawkins does not talk about possible variations among these three categories).
As far as molecules or bacteria are concerned, it is clearly right that this would be all that we are dealing with. In their cases, the “replicator” will be one to one in the copying processes. But it’s hard to imagine this is possible at much higher levels of complexity. What about the environment? What about the fact that genes, say, depend just as much on the organism as a whole as the organism as a whole on the genes?
This comes to Dawkins’ philosophical assumptions. At the end of the chapter, he has a few zingers. After describing a process of proto-carnivorous behavior (where higher level molecules started increasing their own stability and decreasing other’s stability (20) – nice business model, surely), Dawkins mentions how some molecules must have “discovered how to protect themselves…This may have been how the first living cells appeared” (21). Then we get the result: these protections morph into something else. “The replicators which survived were the ones which built survival machines for themselves to live in” (21). The protective coat becomes the machine that houses the replicator that goes on to a blockbuster role in humans. The replicators did not stay in these small houses of chemical or protein walls; they made colonies, and developed new robots. Eventually they get really complex: “they are in you and in me; they created us, body and mind; and their preservation is the ultimate rationale for our existence…they go by the name of genes, and we are their survival machines” (21).
So here we get the first part of his thesis, that we are survival machines. This is certainly an extraordinary statement, but of course, Dawkins tells us (rather sheepishly) "this is a truth which still fills me with astonishment. Though I have known it for years, I never seem to get fully used to it. One of my hopes is that I may have some success in astonishing others" (ix). Well, I for one am astonished. What I am so astonished by is how utterly unbelievable this thesis is. Just think about this notion: a replicator, the gene, is the basic "unit of selection." But what about the rest of the organism? Does Dawkins really expect us to swallow the idea that there is no two-and-fro between the genes and organism, the organism and its group, and the organism/group and its environment? His very explanatory tool for variation - monks transcribing the gospels - is a perfect example of this multi-level unit of selection. Monks mis-transcribed for hundreds of reasons - that one was particularly tired that day; the Carolingian script made the old Latin script even more foreign each time; wars, pestilence, and a whole bunch more stuff. If you said it was all the monk's fault for these errors would just be simplistic.
Dawkins makes a very important point early in the chapter that Darwin’s notion of “survival of the fittest” is “really a special case of a more general law of survival of the stable” (13). This is surely right, and as Evelyn Fox-Keller has pointed out (in her excellent Century of the Gene), species stability is the real hot topic in genetics and other biological sciences these days. In other words, the real question is not “how do things change” but how, given change, what conditions make it possible for a thing to stay the same – or similar – in other words, to survive. For Dawkins, the history of this emergence of stability can be written in terms of Darwinian natural selection from its earliest conception, that primeval soup after the big bang.
To justify this, Dawkins appeals to the idea of molecule stability. Molecules, like hemoglobin, are extraordinarily stable, and if you have a stable molecule (because of its structure), it “will tend to stay that way. The earliest form of natural selection was simply a selection of stable forms and a rejection of unstable ones” (14). So, the basic Darwinian concept of natural selection – which, in Darwin, starts mid-stream, in already complex forms of life – for Dawkins can at least be understood in even the earliest forms of life.
I really do wonder what other biologists make of this argument, and Dawkins doesn’t present much evidence beyond this logical construct. Because stability is the goal (Dawkins uses this type of language), things that are more stable tend to stick around, as opposed to less stable stuff. This of course doesn’t account for the complexity of humans, but this complexity is “where Darwin’s theory, in its most general form, comes to the rescue. Darwin’s theory takes over from where the story of the slow building up of molecules leaves off” (15).
And so Dawkins takes on a “necessarily speculative” journey, with the caveat that “the simplified account I shall give is probably not too far from the truth” (15). The beginning of this story is standard. The primeval chemical soup leads to the building blocks of life, and this means molecules. The innovation (I think – Dawkins cites absolutely no one, so it’s really hard to know, as a science outsider, if this is a common view, or who first thought of it. I find this annoying.) comes in the idea of “replicator.”
Now the concept of “replicator,” and indeed the concept of unit of selection, apparently has been debated quite a bit in the scientific literature. I found a few articles describing this debate (see Samir Okasha on this), and it seems that Dawkins doesn’t really take into account other views, like Hull’s replicator/interactor distinction, or Lewontin’s criticism. But in any case, he presents replicators as having essentially two functions: they re-create the structure of the molecule they copy; and transmit the differences or variations (‘errors,’ in Dawkins-talk) to the next generation.
Dawkins’ replicators have three characteristics: (a) longevity (selected for); (b) fecundity (the rate of production); (c) accuracy (18-19). Finally, these three aspects will be selected for in competition. Those molecules that show the least of these attributes will not survival; those that show the most, will (although Dawkins does not talk about possible variations among these three categories).
As far as molecules or bacteria are concerned, it is clearly right that this would be all that we are dealing with. In their cases, the “replicator” will be one to one in the copying processes. But it’s hard to imagine this is possible at much higher levels of complexity. What about the environment? What about the fact that genes, say, depend just as much on the organism as a whole as the organism as a whole on the genes?
This comes to Dawkins’ philosophical assumptions. At the end of the chapter, he has a few zingers. After describing a process of proto-carnivorous behavior (where higher level molecules started increasing their own stability and decreasing other’s stability (20) – nice business model, surely), Dawkins mentions how some molecules must have “discovered how to protect themselves…This may have been how the first living cells appeared” (21). Then we get the result: these protections morph into something else. “The replicators which survived were the ones which built survival machines for themselves to live in” (21). The protective coat becomes the machine that houses the replicator that goes on to a blockbuster role in humans. The replicators did not stay in these small houses of chemical or protein walls; they made colonies, and developed new robots. Eventually they get really complex: “they are in you and in me; they created us, body and mind; and their preservation is the ultimate rationale for our existence…they go by the name of genes, and we are their survival machines” (21).
So here we get the first part of his thesis, that we are survival machines. This is certainly an extraordinary statement, but of course, Dawkins tells us (rather sheepishly) "this is a truth which still fills me with astonishment. Though I have known it for years, I never seem to get fully used to it. One of my hopes is that I may have some success in astonishing others" (ix). Well, I for one am astonished. What I am so astonished by is how utterly unbelievable this thesis is. Just think about this notion: a replicator, the gene, is the basic "unit of selection." But what about the rest of the organism? Does Dawkins really expect us to swallow the idea that there is no two-and-fro between the genes and organism, the organism and its group, and the organism/group and its environment? His very explanatory tool for variation - monks transcribing the gospels - is a perfect example of this multi-level unit of selection. Monks mis-transcribed for hundreds of reasons - that one was particularly tired that day; the Carolingian script made the old Latin script even more foreign each time; wars, pestilence, and a whole bunch more stuff. If you said it was all the monk's fault for these errors would just be simplistic.
And so Dawkins seems to be. His entire history may be correct (even if speculative), but I find the entire explanation like a simple just so story - like his use of the idea of "affinity" to explain how molecules originally started to replicate. What is "affinity"? What is the relationship between copy and copies? Did the molecules desire one another? Did they fit like puzzle-pieces? Did some force-field push them together? One or none of these may be the case, but Dawkins doesn't say.
But the central problem I see is his use of the machine metaphor. A machine is a thing that an agent makes in order to increase efficiency in some manner. It can be simple or complex, but the basic principle is that there is an input and an output, and the something outside the machine has to put something inside the machine, the machine itself being an inert thing, like a substrate. Humans "create" these machines like genes "create" humans. But at the same time, even in machines with human masters alter the way humans live, how they relate to their world, what they conceive as worthwhile and what they think is ok to do (think about "push-button war" vs. nomadic, hand-to-hand combat). In Dawkins' hands, this sounds completely one-way, as if molecules are using the "shell" (the Ghost in the Shell, as it were) of humans.
Now, if there were only a metaphor - ok. But then you would enrich this account with other metaphors, and you could delimit your subject by qualifying your assertions. Dawkins never does this (except once - when he says it's a "fallacy...to suppose that genetically inherited traits are by definition fixed and unmodifiable [by human behavior]" (3). Well, he doesn't actually point out which fallacy this is, and he doesn't seem to really back this up - at least not yet). It seems as if Dawkins would have to be using "machine" as a metaphor, but he speaks in a much more literal way, so it's hard to discern.
In the end, I found myself wonder what this is, if not an alteration of the old Platonic notion of the dualism of the soul and body. What is changed is the "soul" - it becomes "replicators," the genes themselves - the subject of his next chapter. But the body stays its old self- a hull, something to be cast off in the eternal life of the gene....
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