Posted by DaveScot has a post at UD that perfectly demonstrates the vacuity of creationist probability arguments and Dembski’s “specified complexity.” What he intends as a defense of the concept actually provides all of the ammunition necessary to show why analogies between non-biological processes and biological processes, as they relate to probability, are ultimately meaningless. He admits that specification is “a subjective measure” but argues that it can be identified intuitively, as we do every day. He intends to use a deck of cards as an analogy:
To explain I’ll use a deck of cards and a conclusion that just about any reasonable person, with or without knowing what specified complexity is, will recognize and draw the same conclusion based on it. Then I’ll present a like example from a living thing and ask you be the judge of whether there is specification.
And his example with the deck of cards is okay as far as it goes:
Start with a standard deck of 52 playing cards. You are told that it has been shuffled thoroughly. Upon examination you find that the deck is perfectly ordered by suit and rank. Will you still believe it was shuffled? Probably not. Do you know you’ve based that conclusion on specified complexity? Probably not. Our brains are pattern recognition engines. You reach the conclusion intuitively.
Let’s dissect this with a bit of arithmetic. Any arrangement of 52 cards is as statistically likely as any other. A random shuffle has no preferred order as an outcome. One arrangement is just as likely as any other. My windows calculator says there are 8.0658175170943878571660636856404e+67 possible arrangements. That’s 8 followed by 67 zeroes and is calculated by entering 52 and then pressing the n! button which performs the calculation 52×51×50×49×48…x5×4×3×2. That is the complexity part – the number of possible arrangments is huge and there is no physical law that prefers one arrangement over another. Most people intuitively know the number of possible arrangements is a huge number without knowing precisely how huge.
If any one arrangement is as likely as any other why do we conclude the deck was not shuffled if we find it perfectly ordered by rank and suit? Because we intuitively employ the concept of specified complexity. The perfect ordering is a specification. Specification can be defined as an independently given pattern.
But here is where he tries to form an analogy:
Now let us look at an example of specified complexity that exists in all living things. The video depicts the purpose and action of an enzyme called a topoisomerase. The enzyme is far more complex than a deck of cards. It is a sequence of hundreds of amino acids in a folded chain. Any link in the chain can be any one of 20 different amino acids. The order determines how it will fold and what biological activity (if any) it will possess. Does it have specification? You must be the judge of that.
No need to watch the video. Of course the enzyme is extremely complex. But here is where the analogy quickly becomes absurd for several reasons. The first and most obvious is that it almost certainly is not true that this particular enzyme requires all of those hundreds of amino acids in precisely that order to function. Experiment after experiment on enzyme function, including some generated by ID advocates themselves (see Axe 2000 and 2004), have shown that you can make significant substitutions in enzymes and still have the enzyme function.
Such experiments also consistently show that there are some particular places in an enzyme sequence, such as a binding site, where such substitutions may impair function significantly; but at many other places in the sequence, you can make sizable substitutions and only slightly impair function (and by the same token, you can also improve function slightly, or significantly, depending on which amino acids you change out). Axe’s 2000 paper, for example, shows that you could make up to 20 amino acid substitutions and only have a slight effect on enzyme function; you had to knock out as many as 40 amino acids in order to destroy the function. So any claim that there is only one specific sequence that must be hit in order to have the enzyme function is flatly contradicted by the experimental data, even data generated by ID advocates themselves.
But that’s just the first and most minor problem with the analogy. Another obvious problem is that biological organisms reproduce and mutations can accumulate as they do, something that is not present with the deck of cards. And as hundreds of experiments show, not only can changing out one or a few amino acids in an enzyme slightly reduce the efficiency of the enzyme’s function, they can also slightly increase the efficiency of that same enzyme.
And this, of course, is precisely how evolution operates. A given protein has a given function and a mutation may slightly increase or decrease its ability to perform that function. A mutation that improves function is selected for and goes on, where more mutations later can accumulate and the result is the building of a more and more efficient protein. In biological processes, specification can only mean “function”, while with a deck of cards, one can only define specification according to a preset determination. But if you looked at each shuffle and picked the one closest to the target, then shuffled all the remaining cards and preserved the ones closest, and continually did that, then you could mirror what happens in biological processes. That is one more reasons why the analogy is absurd.
Reason #3: in biological processes, you can also use mutations to change the specification, that is the function of the protein. Again, this is something that is seen all the time in experiments with enzymes. If a given enzyme has one function, mutations can also result in a new function for the enzyme. Sometimes that function is closely related, sometimes it’s not. We see in situations like the nylon-eating bacteria that sometimes a mutation or series of mutations can, in a very short period of time, result in an entirely new function, in that case the ability to metabolize a material that did not exist only a few decades earlier.
Lastly, there is one more problem: biological processes allow for simultaneous rather than sequential trials. If you’re looking at a particular enzyme in a bacteria, for example, you’ve likely got a pool of trillions upon trillions of that particular bacteria in the world, all reproducing at an extraordinary rate. Unlike the deck of cards, where you have one shuffle to find one sequence out of 8^67 possible sequences, in the real world of biological evolution you’ve got trillions of decks being shuffled all at once, every single generation, with a remarkably fast rate of generation. All of those things demonstrate the absolute meaninglessness of creationist probability arguments.
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