Is Specified Complexity Smuggled into Evolutionary Algorithms

Dembski suggests a modification of Dawkins's weasel algorithm. In his adjusted procedure, the algorithm will "pick a position at random in the sequence. . . . Then randomly alter the character in that position. If the new sequence has a higher fitness function than the old, keep it and discard the old. Otherwise keep the old. Repeat the process" (193). I will discuss the fitness function later in this chapter. For now, suffice it to say that the fitness function is the number of letters in the intermediate phrases that coincide with the letters in the same positions in the target phrase.

I see no substantial difference between the procedure described on pages 47-48 in Dawkins's book and that suggested by Dembski. In Dembski's view, while Dawkins's algorithm compares consecutive phrases with a target, his own modified algorithm "searches for the target solely on the basis of the phase space and the fitness function," hence "not smuggling in any obvious teleology" (194). But the only difference between Dawkins's algorithm and Dembski's modification is in the way in which they simulate mutations. Otherwise, both compare intermediate phrases with the target. In Dembski's version, the values of the fitness function are simply the counts of those letters in the intermediate phrases that coincide with the letters occupying the same positions in the target phrase. Indeed, we read, "As before, fitness is determined by how close a sequence is to the target sequence" (194). Therefore, Dembski's modified algorithm is as teleological as Dawkins's original algorithm.

Continuing, Dembski insists that evolutionary algorithms cannot generate specified complexity (SC) but can only "smuggle" it from a "higher order phase space" (194-96). This claim is irrelevant to biological evolution. In the case of the weasel algorithm, the outcome is deliberately designed. SC is injected into the algorithm through the fitness function. But since biological evolution has no long-term target, it requires no injection of SC. Natural selection is unaware of its result—the increased chance for having progeny. The advantage in proliferation occurs automatically. If Dembski thinks otherwise, he needs to offer evidence that extraneous information must be injected into the natural selection algorithm, apart from that supplied by the fitness functions that arise naturally in the biosphere. He provides no such evidence.

Furthermore, in Dawkins's weasel example, the evolutionary algorithm converges on a meaningful phrase: a quotation from Shakespeare. According to Dembski, the target phrase possesses SC. Michael Behe, in a foreword to Dembski (1999), gives an example. While the meaningful sequence METHINKSITISLIKEAWEASEL is both complex and specified, a sequence NDEIRUABFDMOJHRINKE of the same length, which is gibberish, is complex but not specified. Many of Dembski's statements scattered throughout his publications make it clear that Behe has indeed correctly reflected his position (Perakh 2001b, 2003), which is that a meaningless sequence possesses no SC.

On the other hand, Dembski (2002b, 195) indicates that Dawkins's algorithm could also be applied if the target phrase were gibberish. But if the target sequence is meaningless, then, according to Behe's quotation, it possesses no SC. If the target phrase possesses no SC, then obviously no SC had to be smuggled into the algorithm. Hence, if we follow Dembski's ideas consistently, we have to conclude that the same algorithm smuggles SC if the target is meaningful but does not smuggle it if the target is gibberish. This notion is preposterous because algorithms are indifferent to the distinction between meaningful and gibberish targets.

This inconsistency in Dembski and Behe's approach stems from the fact that the very concept of SC is contradictory. In fact, contrary to their notions, both a meaningful phrase and a string of gibberish are specified if the concept of specification is given back its commonsense meaning by clearing it of the embellishments and unnecessary complications suggested by Dembski (1998a, 1999, 2002d). By having written down a gibberish sequence, Behe has clearly specified it. As soon as it has been written, it becomes unequivocally distinguishable from any other sequence, which means that it is specified. Whether it is meaningful or gibberish is of no consequence (Perakh 2001b, 2003).

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