Monday, January 26, 2009

 

How not to win an argument with a creationist

The February 2009 edition of BBC Focus magazine boasts a 12 page special on Darwin in celebration of the bi-centenary of his birth. For me, the stand out article is an interview with zoologist Richard Dawkins entitled 'How to win an argument with a creationist' (p. 46)

Is Evolution Random?

Dawkins begins by attacking the common, mistaken, simplistic idea that evolution is nothing but 'a theory of random chance' by saying:

'...natural selection is really the opposite of chance, it's non-random survival.'

Well, yes; natural selection isn't random survival, it's survival of whatever happens to be the relatively 'fittest' under whatever environmental conditions happen to obtain at the time of selection (which means that the process doesn't exactly exclude random events).

But of what is natural selection the supposedly non-random survival of? Of random mutations! And it's the random mutations that have to do all the accounting for the arrival of the fittest at each iteration of the natural selection process!

Dawkins' Central Argument

According to Dawkins, a second common creationist mistake is to 'think design is a feasible alternative to chance, which it isn't.' Why not? He says:

'If you think about something as complicated as an eye, yes, it's absolutely right to say that it can't have come about by luck, but equally any god capable of designing it can't have come about either.'

Now, this is a very strange argument - a summary of Dawkins' 'central argument' in his book The God Delusion. First off, design clearly is a feasible alternative to chance - just consider human artifacts like cameras or cars! In these instances, design is clearly a superior explanation to chance - indeed, design is clearly the best explanation tout court. In fact, Dawkins himself not only admits this, but he even admits that life on earth might possible be the result of intelligent design - just as long as the designers are aliens with an evolutionary explanation!

So according to Dawkins design is actually a feasible alternative to chance unless one is considering the question of life's ultimate origin. And this tips us off to the fact that his objection is philosophical and not scientific. His philosophical objection is that any god able to design something like an eye 'can't have come about either' - presumably that's 'can't have come about by chance either'. Indeed, it does seem implausible to think that a god could come about by chance (by design - I'm not so sure: Perhaps it depends who the designer is meant to be - although this thought does suggest a regress of designers that would presumably have to stop somewhere)! But, then again, if we're talking about the God of mono-theism - God with a capital G rather than a small g - then no monotheist thinks that God came about by chance (or by design); or, indeed, in any manner whatsoever! God did not 'come about'! Thus Dawkins' objection simply begs the question against the existence of a designer who did not 'come about' - an un-made maker, a first cause, a necessary being. That is, the sort of being monotheists classically think God to be!

The Eye's Have It

The BBC interviewer then asks Dawkins a question about 'irreducible complexity' - which, par for the course, the interviewer defines incorrectly. Dawkins responds by talking about simplistic creationist arguments to the effect that half an eye is useless and that 'you need to have 100 percent of an eye' to have something natural selection could work upon. This is, as Dawkins says 'obvious nonsense'. So obvious, indeed, is this nonsense that one wonders if there can be many creationists who argue this way.

Here are some examples of actual creationist arguments about the eye:

David N. Menton, "Can Evolution Produce an Eye? Not a Chance!"
Answers in Genesis, "An Eye For Creation"
Peter W.V. Gurney, "Is Our ‘Inverted’ Retina Really ‘Bad Design’?"

However, Dawkins completely sidesteps the question of how one accounts for the origin of the supposedly simple light-sensitive spot with which evolutionary accounts of eye's ubiquitously begin... As Michael J. Behe argues in Darwin's Black Box, it is the light sensitive spot which is the irreducibly complex core of the eye:

Dr Michael J. Behe, "Molecular Machines: Experimental Support for the Design Inference"

Dr Michael J. Behe, "Evidence for Intelligent Design from Biochemistry"

Improving partial vision by evolution is, to say the least, much easier that gaining vision. And what about the neural, brain capacity for interpreting those electrical signals as vision. And how about accounting for the conscious feel or qualia of sight? Dawkins remains silent on such issues, as does Darwinism.

Also on Eyes, cf: ARN: "New Theories on the Origin of the Eye"; ARM: "Fine Tuning of the Squid's Lense"; Lucy Sherriff, "Living Optical Fibres Found in the Eye"; George Ayoub, "On the Design of the Vertebrate Retina"; Michael J. Denton, "The Inverted Retina: Maladaption or Preadaption?"

Fine Tuning

Dawkins considers the fine tuning of the cosmos the most interesting potential basis for a theistic argument:

'There are some half a dozen or so fundamental physical constants. physicists have no explanation for why they have the value they do, they just accept that the constants have those values and calculate that if they had different values the Universe wouldn't work and we wouldn't be here.'

The argument based upon this fact is brushed aside with a repetition of the claim that it 'still leaves open the question of who designed the designer'. Phrased this way, Dawkin's 'central argument' appears to count against all scientific explanation, in that it appears to assume that one cannot explain A in terms of B unless one has an explanation for B in terms of C, and so on ad infinitum! If one rejects this assumption, one must acknowledge that it can be legitimate to explain A in terms of B even if this does leave B wholly unexplained!

The Origin of Life

Dawkins admits that from his point of view the origin of life is an unexplained conundrum:

'the origin of life is an interesting question because, unlike everything else about life, which can be explained by natural selection, the origin of life strictly can't... a self-replicating entity is a pre-requisite for natural selection, so therefore we can't use natural selection, at least in the ordinary sense, to explain it. So, to that extent, the origin of life has to be a chance event.'

Dawkins then professes his blind faith in the proposition that the origin of life wasn't all that unlikely: 'The sheer number of planets in the Universe on which life could have arisen entitles us to postulate a very high level of chance for the origin of life.' Oh yes, how many planets is that exactly? We only know of one for sure, and we're living on it! In The God Delusion Dawkins guesstimates a number of planets in the universe that pales before the estimated odds against abiogenesis - and even this educated guesswork gratuitously assumes that every planet is capable of supporting life! But the latest evidence indicates that Earth is a rather special place in terms of its life-bearing capacity.

Conclusion

I'm no creationist. I support intelligent design theory, but that's a different kettle of fish (the interview unfortunately conflates the two.) However, it seems to me that Dawkins' advice isn't going to help Focus magazine readers 'sitting opposite a creationist in the pub' very much.



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