by Joe Felsenstein http://evolution.gs.washington.edu/felsenstein.html
In a discussion here of the views of the creationist Cornelius Hunter I posted a comment with a summary of his views about Bad Design arguments. I argued that
what he has just done is to admit that the hypothesis of a Designer is not science, as it predicts every possible result. If you predict every possible outcome, the ones that are seen and the ones that are not, then you have not predicted anything!
At his own blog Hunter objected strongly, saying that
Unfortunately these misrepresentations are typical of evolutionists. Not only are evolution’s metaphysical arguments from dysteleology, or bad design, perfectly valid, they can also be quite powerful. Felsenstein’s strawman that we say otherwise would be bizarre if it wasn’t so common.
Was I wrong?
Hunter certainly did endorse bad-design arguments in a post on 27 July at his blog “Darwin’s God”. He reacted to Jerry Coyne’s example of the bad design of the giraffe recurrent laryngeal nerve by saying that
Evolution has no scientific explanation for how the recurrent laryngeal nerve, or any other nerve for that matter, evolved. It is a vacuous theory. But it knows they must have evolved because God would not have done it that way.
In fact, evolution has no solid basis for even thinking these designs are necessarily poor. This is more religion making its way into the argument, as the assumption of poor design is itself a motif of evolutionary thought.
Hunter thinks arguments from bad design are potentially powerful, but when Coyne makes one, Hunter argues that the path of the recurrent laryngeal nerve might be a good one, and that Coyne can’t prove that the design is actually bad. And he will do that no matter where the nerve zigzags to.
Does he have a scientific theory about that nerve? I haven’t noticed one.
This approach is not confined to bad-design arguments. Take the evidence for common descent. Note Hunter’s reaction to David Penny’s work verifying common descent. Penny’s paper compares the fit of common descent to a null hypothesis of no common descent.
In that 1991 paper Penny and his collaborators compared phylogenies inferred from 18 different protein loci. Using the null hypothesis that each locus had a different, randomly selected tree, they could firmly reject that and conclude in favor of common descent, as the 18 trees were far more similar than would occur at random.
To Cornelius Hunter, the null hypothesis that Penny et al. used
attacks design or creation using non scientific premises that a design or creation advocate would not recognize.
One immediately wonders: To avoid making this supposed religious presupposition, what should Penny et al. have done? What are the “scientific premises” that a design or creation advocate would recognize?
If there are none, then the Design he speaks of is an infinitely flexible hypothesis that predicts nothing, and thus is really not a scientific hypothesis at all … which is what I originally said. Hunter has objected to my statement. So what in the way of a scientific hypothesis does he offer instead?