In Defence of Darwinism: The Ignorable Berlinski part 2
First, a few points on style
In an episode of The Simpsons, Homer has the following exchange with Lisa, after she announces her intention to become a vegetarian.
Homer: Are you saying you're never going to eat any animal again? What about bacon?
Homer: Pork chops?
Lisa: Dad, those all come from the same animal!
Homer: Heh heh heh. Ooh, yeah, right, Lisa. A wonderful, maaagical animal.
You know how cringe-worthy it is when you're discussing something with someone who, to put it as politely as possible, isn't very bright, and after they run out of arguments they resort to clumsy sarcasm instead? Painful, isn’t it?
Reading Berlinski’s article “The Deniable Darwin”, which appeared in ‘Commentary’ magazine in 1996, is a bit like that. He hasn’t got all that much to say and he knows it, so he pads what should be a brief article of a few hundred words into a long and tedious tirade by adding reams of sarcastic purple prose.
(The most grating of these passages being his little coda designed to ‘mock’ the idea that random natural selection can create complexity, where he imagines a conversation with “Jorge Luis Borges one evening in a Buenos Aires café”: “I raise my eyebrows. Borges pauses to sip discreetly at the bitter coffee our waiter has placed in front of him, guiding his hands to the saucer.” And so on ad nauseam.)
All very well, and great fun for Berlinski I’m sure, but this bumf serves no purpose other than to obscure what little actual ‘argument’ he makes. Trim this fat to find the meat beneath, and the offerings are scrawny in the extreme.
The first five or so sections of the essay could be summarised thus:
1. The evidence for the Theory of Evolution is in some instances incomplete and open to more than one interpretation
2. Darwinists disagree with each other over certain things
Both true enough, but hardly earth-shattering. Of course you can interpret any evidence in different ways. The question is, which is the best explanation? Of course Darwinists disagree with each other about certain things. But they agree about some things, and those things are the content of the TofE which any opponent must address if he wants to undermine it.
Note that while Berlinski is held up as a leading light of the ‘Intelligent Design’ movement, none of these points are actually positive arguments FOR anything in particular. They’re just general attacks on darwinism.
The meat, such as it is, of his essay depends on the claim that darwinism’s account of ‘purely random’ mutation cannot account for the complexity and variety of life which we see in evolution and the natural world.
Berlinski argues for this in two ways, both of which appear in the sections “The Artificer of Design” and “The Head Monkey”.
(for this part of my article I am significantly indebted to H. Allen Orr, who is quoted by Berlinski as support, but who actually refutes ‘The Deniable Darwin’ in a letter to Commentary magazine)
The first argument, which I’ll call the ‘Language Jam Argument’, goes like this:
1) Darwinian evolution is based upon the notion of random mutation plus natural selection, at the level of DNA.
2) DNA is a discrete "alphabetic" language of A's, T's, G's, and C's that carries the code for all the phenotypes we find in organisms.
3) But random changes in languages, eg. English, creates gibberish.
Therefore, darwinism asks us to believe that evolution depends on random changes, when, by analogy with any other language, you should get gibberish – resulting in organisms being hopelessly ‘jammed’.
The argument is at least more sophisticated than the normal ‘how can random mutations create complexity’, in that he acknowledges that darwinism involves random mutations plus nonrandom selection for fitness.
But the flaw in Berlinski’s Language Jam argument is pretty obvious: it ignores the known facts. While random mutations which do render an organism so helpless that it dies are indeed common, so are all sorts of random DNA mutation which happen but simply do not ‘jam’ organisms. In fact, you need pretty sophisticated chemical science to find them at all.
As Orr puts it “The existence of subtle, functional, usable mutations in DNA is a simple fact that no amount of analogizing with computer programs can make go away. That random changes in computer programs -- but not DNA -- invariably jam things does not show that there is something wrong with Darwinism but that there is something wrong with the analogy.”
Actually, it’s worse than that for Berlinski. In another reply to the article, Karl F Wessel points out that numerous computer programs have in fact been run which replicate the processes of natural selection but do not ‘jam’:
The heart of David Berlinski's argument has been experimentally refuted, a result that is of more recent vintage than the obsolete mathematical metaphor he employs. In a 1986 experiment performed by Marshall Horwitz and Lawrence Loeb of the University of Washington, 19- base long messenger RNA promoter sequences were deleted from the genomes of E. coli bacteria and replaced by randomly synthesized sequences. Of the approximately 1011 possible sequences of the type, it turned out that many promoted the function of the deleted natural sequence (which confers resistance to tetracycline) as well as or better than the original. This was true even for a small subset of sequences randomly generated from two bases, i.e., from far fewer than 106 of the 1011. Nor did some of the most efficient sequences at all resemble the original.
Given this outcome and others like it, it is clear that something is radically wrong with Mr. Berlinski's analogy of biological genomes to computer programs. Either ge-nomes are nothing like programs, or else at least some programs are far more robust in the face of effects resembling natural selection than he imagines.
In point of fact, for several years people like John Koza of Stanford University have been using analogs of natural selection to evolve computer programs. Many of these evolved programs perform their optimizing tasks better than the best intentionally designed ones, providing the reductio ad absurdum of Mr. Berlinski's criticism.
So much for the Language Jam Argument.
The second argument against randomness producing complexity, which I’ll call the Monkey-Typewriter Target Argument, goes like this:
Berlinski starts with Dawkins’ famous analogy of the monkeys bashing at typewriters until they create an exact phrase from Shakespeare: “Methinks it is like a weasel”. The point of the analogy is to show that even though it would take billions of years for the monkeys to get this phrase if they were randomly hitting the keys, if you model it like evolution, saving each match and building upon it as in a recursive system, it doesn’t take that long for them to get it at all. So you have random mutation (the typing), plus natural selection (saving the matches to the original phrase each time, ie. once you’ve got the ‘M’ you save it and keep going til you’ve got an ‘e’, then save, then a ‘t’ and so on.)
Berlinski attacks this analogy by insisting that to have a ‘target’ of the phrase, you must have some kind of designer or monitor (a ‘Head Monkey’ ) who is overseeing the project, to make sure that all the time we’re getting nearer to our target of the phrase. Otherwise how will the monkeys know which letters to save? So in other words, darwinism, far from discarding a Designer, needs one to define the target and show how close we are to it.
So that’s the Monkey-Typewriter Target Argument. Can you spot the flaw? What is the original monkey typewriter analogy intended to show? It shows that, by saving favorable random changes, evolution can gradually build complex structures. So you do not need to wait for each part of a structure (all the letters in a phrase; the wings, eyes, feathers, digestive system etc of a bird) to appear miraculously at once. Natural selection is recursive: the output of the last generation feeds into the input of the next. It builds upon itself.
But, as Orr puts it in his response to Berlinski, the original analogy: “completely flubs another part of Darwinism: evolution does not, of course, work toward any "target." So how, then, does evolution know where to go? The answer is the most radical and beautiful part of Darwinism: it does not. The only thing that "guides" evolution is sheer, cold demographics. If a worm with a patch of light-sensitive tissue leaves a few more kids than a worm that cannot tell if the lights are on, that is where evolution will go. And, later, if a worm with light-sensitive tissue and a rough lens escapes a few more predators, that is where evolution will go. Despite all the loose talk (much of it, admittedly, from evolutionary biologists), evolution knows nothing of "design" and "targets."
So Berlinski ignores the non-teleological element of darwinism – which is absolutely fundamental and basic – and misinterprets the monkey-typewriter story as if it was meant to be a perfect analogy of all evolution, and not just a way of showing how natural selection builds upon itself.
I don’t think Berlinski is completely stupid, so I have to assume he does it deliberately, which is pretty poor show.
Balancing the scales
Let’s conclude with Berlinski’s own conclusion:
NO DOUBT, the theory of evolution will continue to play the singular role in the life of our secular culture that it has always played. The theory is unique among scientific instruments in being cherished not for what it contains, but for what it lacks. There are in Darwin's scheme no biotic laws, no Bauplan as in German natural philosophy, no special creation, no elan vital, no divine guidance or transcendental forces.
On the contrary. In lacking a recourse to divine guidance and transcendental forces, and in trying to work out the physical mechanisms for how something works without relying on magic, myth or mumbo-jumbo, darwinism is exactly like every other scientific theory worthy of the name.
What's unique is that darwinism is the only theory that is vilified for lacking these things. Nobody has an Intelligent Design theory of plate tectonics or diamond formation. If darwinism was limited only to explaining the natural history of plant-life, for example, I doubt there would be any such thing as an 'ID' objection.
ID exists because some religionists (not all) feel that darwinism threatens their beliefs. ID, with its false veneer of 'scientific enquiry' and its dressing of technical language, exists because Creationism has become an impossible position to hold and be taken remotely seriously. But ID is not a theory with any evidence from the natural world. There is only one source of positive evidence for it, which it shares with Creationism: the Old Testament.
To paraphrase a famous comment Salman Rushdie once made:
On one side of the scales is the Theory of Evolution: a massive body of incomplete, imperfect, but nonetheless considerable and ever-growing knowledge, painstakingly acquired from in-depth study of the natural world and constantly reappraised and tested. On the other is the Book of Genesis.
Only in Cloud Cuckoo Land, Kansas and Berlinski's head do the scales balance.