From Massimo Pigliucci at Footnotes to Plato:
Intelligent Design proponents and assorted creationists, for instance, have often pointed to alleged instances of “irreducible complexity” in the living world: biological systems that are so intricate that they could not possibly have evolved. In dealing with such challenges, evolutionary biologists can suggest possible evolutionary pathways leading to a given complex biological structure. When they have done so, there is an extra BoP [burden of proof] on ID advocates to rule out all of the proposed natural explanations. Contrary to what believers think, the BoP is not on skeptics to demonstrate which one of the natural explanations is the correct one. Given the overwhelming evidence for the power of natural selection to produce adaptive complexity, and the difficulty of garnering information about a distant evolutionary past, this kind of informed speculation is all that is needed to put ID arguments to rest (of course, evidence of specific mutations and selection processes further strengthens the case for evolution, but its fate no longer depends on it). The amount of anomalies (in casu, evolutionary puzzles) has simply not come even close to the Kuhnian threshold for a paradigm shift, though of course this says nothing about whether it might do so in the future. More.
First, we are astonished at Pigliucci’s grand claims for the tautology of “natural selection” to produce adaptive complexity which is about as well demonstrated in the real world as magic.
Second, no one applies the standard he suggests (rule out all of the proposed natural explanations [= explanations my crowd favours]) if anything important is at issue. As it happens, the evidence does not favour his crowd’s explanation.
For one thing, anyone can suggest “possible evolutionary pathways” without limit. No one can rule out all possible explanations, however unlikely, in this universe—or one of an infinite multiverse that may intersect with ours (as we sometimes hear).
When making decisions, we usually use an inference to the best explanation. Only textbook Darwinism and the ever-supportive multiverse are exempt. But why are they always sheltered that way?
See also: The multiverse: The long march of progressive politics through science institutions