Intelligent Design is not a Theory

There are religio-political factions who wish to have the teaching of Darwin's theory of evolution in public schools suppressed in favour of a theory of intelligent design. The basic crux of their argument is that: there remain controversies in science, which they ask us to interpret as grounds for doubt about the basic tenets shared by the assorted parties to these controversies; in the presence of such doubt, they ask us to accept without critical thought a set of claims they present that they claim are as valid as the basic tenets shared among those whose controversies they pointed to.

There is absoluptly no basis for that argument. Even if you could prove that evolution was outright wrong, that would not amount to a single jot of data towards establishing any other theory. It would leave a space open for other theories to attempt to claim, but they would have to stand up to at least as rigorous a critique as the ousted theory. If you do not provide any evidence for your own pet theory, no amount of evidence against an incumbent theory is any help in persuading science to accept your theory.

Howevever, let waste no more time with tha intelligent design camp's failure to say anything testably true and at odds with the theory for which they claim to be a substitute. The fundamental failing of intelligent design is that it is not a theory.

What is a theory ?

We would, of course, like our theories to deliver everything: a complete description and explanation of everything (at least within their domain of relevance), sufficient to predict everything. In practice we don't have many of those outside the formal domain of mathematics, where Humpty-Dumpty is King: if you are at liberty to make up your own rules, sometimes you can decisively answer some of the questions those rules admit you should be able to answer. Science develops theories which attain as much as is practical of that precious goal: a theory need not be perfect to be good, illuminating and, crucially, useful.

So, realistically, what should we expect of a theory ?

On all three of these things, intelligent design fails abysmally. It does not matter what faults in the best available theory you are able to point to, if what you claim to be offering in its place is not better, then it is not worthy of being taught as a credible alternative. When it is not even a theory, it is not an alternative at all, let alone a credible one.

The proponents of intelligent design endeavour to account for the emergence of the most basic forms of life by postulating a form of sentient intelligence significantly more complex and sophisticated than the life-forms we are actually able to document as existing on our home planet. It claims to account for simple things by asking us to believe in something vastly more complex than the things we know exist. The reverse might qualify it as a theory: being the wrong way round is just silly. Since its proposed explanation adds another thing – the designer – whose existence it fails to explain, it actually leaves more to be explained, after its attempt at explanation, than before.

The only questions the proponents of intelligent design are able to claim they answer are those whose answers we knew before they prposed their answers. They give us no questions that we can answer and report back to our peers: the only questions they claim to be able to answer are

The former says nothing: the latter tells me that they understand primate social dynamics – despite denying its relevance – well enough to apply it to the social insecurities of their audience. One might forgive them the former as delusion and stupidity: but the latter smacks of outright cynical manipulation. Science sets out to change someone's mind by presenting evidence and reasoned argument; when someone tries to bring me round to their way of doing things by bribery and threats, I tend to suspect they are aware that they cannot live up to that simple standard; and even that they came by their beliefs by the same means they attempt to use on my, not by any form of reasoned enquiery.

The proponents of intelligent design make a lot of noise about the fact that science is unable to give a blow-by-blow account of every single molecular change in the early history of life on our home planet; and they make much of their claims that they know exactly everything that happened in the course of life's emergence from a universe without life. Science is rightly contemptuous of their sound and fury, on both sides. We have almost no data at our disposal as concerns the earliest history of life's emergence: furthermore, we have ample grounds to expect that we should have little data on this point. Science's account of the matter postulates simple life-forms being dominant until the emergence of such complex life-forms as have differentiated body parts (without which there are no fossils). Science doesn't claim to know any details before such recordable details existed: but has several candidate accounts – of how the origin of life might hasve proceeded – that fit well with its account of the matters about which it does make definite claims.

The proponents of intelligent design claim to have a full account of how everything went, from the get-go: but they wholly and utterly fail to answer any questions at all about the molecular changes leading to life as we know it. Quite apart from their abject failure to account for the existence of the intelligent designer, they also utterly fail to account for – or even provide a framework within which to account for – the very things they complain against Darwinism for failing to do. They are unable to explain the things we do observe, yet make very clear and definite claims concerning matters about which we have least knowledge.

Science makes definite and testable statements about the world we live in, fits these into a coherent model and observes that extrapolating this model can credibly give answers that we cannot test; intelligent design makes an entirely untestable claim about something we cannot test, and extrapolates from it various nebulous claims about how we should live our lives but nothing about the actual nature of life as we find it in the world today, let alone anything testable. Its proponents have the gall to complain that science reports some of the things it can extrapolate about matters we cannot test: but only science has anything useful to tell us about our world.

Who is this imbecile anyway ?

Have you accually looked at life in detail ? If you claim it arose from intelligent design it's about time you did. Proponents of this idiotic scheme claim that the eye is a prime example of how stuff couldn't arise by an evolutionary approach so must require an intelligent designer. They make this claim despite the clear and well-documented analysis by which assorted proponents of Darwin's science have explained the evolution of the chordate eye. But wait a minute: the chordate eye (what you and me have, along with loads of other fish, reptiles and mammals) has a huge and stupid design flaw in it. We have a blind spot. Surely an intelligent designer wouldn't make such a ridiculous mistake ?

Proponents of intelligent design argue that half an eye would be no use at all – revealing that they haven't understood the theory they're trying to undermine. In the land of the blind men, the one-eyed man is king: just so, in a world populated by sightless creatures, the fish with light-sensitive tissue under patches of its skin has some advantage over those without – it gets clues, however poor, about its surroundings. The story never goes via half an eye: it goes via a succession of slightly better ways of making use of a patch of skin with light-sensitive tissue under it. It works better if the skin is more transparent. It works better if the light-sensitive layer dimples inwards (which gives better directional sensitivity). For the outer surface to keep its shape, that requires the skin to be thicker; and if it's not very transparent that doesn't work well; so trapping a layer of water between skin and light-sensitive tissue works better. This makes it easy for the inward dimple to go further and, by forming a cavity, attain much better sensitivity to direction. Subtle variations in the thickness of the layer of transparent skin then confer further advantages by focusing the light; each improvement makes this better until a lens is formed. At each step along the way, a modest change in something pre-existing yields some advantage, that advantage translates itself to a larger population exhibiting the new trait and sets the stage for further changes. But let us leave aside the evolutionary explanation and turn to what we may infer, if we suppose the eye to have been designed, about its designer.

Any idiot designing a system for collecting light, focussing it to an image and collecting the image data for processing by an information-processing system would, as a matter of course, given basic knowledge of optics, put together a lens (or a bunch of boundaries between optical media of differing refractive indexes, which amounts to the same thing, but can be flexible), a hole in which to mount it (ideally with some scope for varying its apperture, so as to balance the competing requirements of more light but finer focus) as light's sole entrance to an otherwise dark cavity and an image capture system, wired to whatever image=processing system is intended to be receiving the results. Any designer would rapidly enough realise these aspects of the design are necessary. But only an idiot designer would have the wiring from the image-capture system (i.e. screen sensitive to light) intrude into the darkened cavity through which the light has to pass from lens to image-capture screen. The most blindingly obvious solution, which even a quite severely dumb designer can reasonably be expected to come up with, is to have the image capture aparatus receive light from one side (the cavity) and have its wiring go out to the image-processing system from its other side.

Now, of course, it's conceivable that this Obviously Correct Solution to the problem is impossible to implement, for one reason or another: in that case, one could accept that even an intelligent designer might roll out a design containing the defect of an image-capture apparaturs in which the wiring which carries information to the image-processing infrastructure must compromise its effectiveness as a data-transport in order to be transparent and have exactly the same refractive index as the medium into which it intrudes; only in such circumstances could one countenance an even half-way competent designer lumbering us with an eye in which part of the image-capture screen has to have a significant hole in it to let the wiring out. Otherwise, imposing these burdens on its deeign would be preposterous. It would be obvious to an idiot that having the wiring go out of the back of the eye would let the eye collect its image from the whole screen, without any need for a hole and consequent blind-spot. Any half-way competent designer would also realise that the wiring is bound to wear out: if it has to intrude into the image-forming light-path, even if it is transparent and does have the same refractive index as its context, the fragments into which it falls apart are going to mess up the image.

Well, guess what ? Squids, octopuses and kindred creatures have exactly the kind of eye that an even half-way competent designer would come up with; so we know it's not impossible. Only these cartilaginous sea creatures have that kind of eye: every kind of creature that has a back-bone – a spinal column, or notochord, marking its owner as a member of the broad classification chordata – has the exact same stupid bug in its eye's design as we have, which lumbers us all with a blind spot in each eye – because the nerve fibres carrying signals from our retinas to our brains intrude into the eye's light-path (instead of simply going out the back of the retina) and so need a hole in the retina through which to be bundled. We also have minor visual problems (they get quite severe for some folks) caused by fragments of dead nerve cell floating about in the light-path of the eye, messing up what we see. The cartillagenous sea creatures are ample proof that the correct solution is possible: yet everything with a back-bone has an eye whose retina is wired back-to-front.

Evolution explains the association of the mis-designed eye with the notochord quite straight-forwardly. Since the nervous system mostly needs to report on the outside world, it has rare tendrils that go out to the skin and a rich network of tendrils running just under the skin. It then suffices to have some early chordate creature with a light-sensitive layer slightly further under the skin, so that the nerve cells are just outside it; that would suffice to leave the nerve cells on the outward side of the light-sensitive tissue for the rest of the story, accounting neatly for the inconvenience of our blind spot. No sequence of small adjustments starting from there can get to the right way round eye without going via forms of eye which are worse than the one we have, so evolution will never fix it. Given an early chordate species with half-way decent eyes, marred by a blind spot for these reasons, evolution predicts that all its descendants will be chordate and have eyes with this defect.

Now, if life had a designer, who clearly Got It Right for the cuttle-fish and their cousins, one must reasonably ask why the designer chose not to use that design for chordate creatures. Furthermore, it is reasonable to ask why this design decision exactly correlates with the decision to include a notochord. Why do we see no cartilaginous sea creatures whose retinas are back to front, and no chordate animals with eyes the right way round ? The designer suddenly seems very whimsical in light of this: and it only gets worse when we observe the myriad of other little details – the more of them two species have in common, the more closely they generally match one another. If we consider two quite different traits – the detailed molecular structure of the gene coding for some standard enzyme involved in the Oxygen cycle of all cells, say, and the shape of the pieces of bone at the upper ends of the jaw – we find that similarity in one trait is generally closely correlated with similarity in the other. How can intelligent design explain these correlations ? Of course, good design does re-use patterns in many places; but it has no reason to restrict where it re-uses patterns in such a tighly correlated way: departing from the correlations would offer many ways to design better creatures – like owls and humans without blind spots.

Resorting to The Lord moves in Mysterious ways is nothing but a cop-out: it amounts to saying our so-called theory has no predictive power, please stop asking us to use it for the single purpose that would give science some reason to pay any attention to it. You are welcome to your religion: just please don't mess up science by asking us to teach a really dumb mis-interpretation of a Judaic folk story as if it were science when it, quite plainly, isn't.

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Written by Eddy.