(Foxy's latest here reminded me that this should have been cross-posted from PowerUp, but I forgot. Oh well, better late than never.)
Abbie has her latest post up describing her experience of Dembski. This is pretty much the first post in the series that has any relevance to my particular area of study (I'm not a biophreak, unlike most of those who post at ERV). You'll likely not be surprised that Dembski managed to bend over and fart out some pseudomathematical silliness before the day was done. But this pseudomath is extra special, as it doesn't even approach the level of coherence. Quoth Dembski (or ERV quoting Dembski):
Dembski-- Whe whe whe we can do a Bayesian analysis! Ahhh, your and my probabilities of a designer are very different. So it would be better to have a methodology that didnt require probabilities for a designer.
*audience laughs again*
Dembski-- Weh we can do a Bayesian sort of thing, given to me it is infinitesimally small I mean, you know, I mean... Here is a standard example.. weeh ehhh beyhh... we need to do this for the sake of the audience. Eeeh you hear some sound up in the attic, you know? Sounds like gremlins, ehh, bowling. Bowling. Gremlins bowling. Thats ahh, would be ahhh, you know, that would explain it. Eh eh, highly unlikely that you know. If there are gremlins up there, bowling, then that would explain the sound. But whats the prior likelihood of there being gremlins? Its highly improbable. So even though if there were gremlins it would explain that, the high improbability that there are gremlins means dont give that explanation a second thought. I think thats how the design hypothesis works for you. For others it doesnt work that way. Okay? So in a sense, if were going to decide this issue, its not going to be on the basis of assigning some sort of prior probability of design. You have to look at the actual improbabilities of this evolutionary system. The thing is, nobody that I see has been trying to do that sort of move. I mean, Richard Dawkins does not try to look at the prior improbability of god, hes trying to say "Look, its highly probable you get these systems because when you do the analysis, Darwinism is a strategy that can climb Mount Improbable", thats his whole point!
Okay, so he's doing a Bayesian analysis without assigning a prior probability to what is (presumably) the "design hypothesis". Let us recapitulate elementary statistics and probability. Here is Bayes rule.
Pr(Hi|D) = Pr(D|Hi)P(Hi)/Pr(D)
That P(Hi) thing in that little relation is known as the "prior" probability. It is typically understood as the probability of Hi being true before the observation of any data. The "posterior" probability, however, is the conditional probability Pr(Hi|D) of Hi being true after the observation of data set D. So you may find yourself wondering how the hell Dembski is doing a Bayesian analysis when the hypothesis he obviously favors (design) lacks the assignment of something fundamental to Bayesian analysis. ERV hit it in her post:
What I liked about this exchange is that it once again demonstrates that IDC is a negative argument. THEY dont have to provide probabilities of a designer. They just have to declare an evolutionary system impossible and declare victory.
It's what I and several other people have been saying all along about Dembski and his charlatanry. What he intends to do is eliminate other existing and mutually exclusive hypotheses so that he can assert that "design" is an alternative. If you take a course in logic, rhetoric and exposition, you'll learn that this little shuffle is known as an "argument from ignorance". In theological circles, the same tactic is known as a "god in the gaps" argument. Either way, it's an elementary fallacy. Unfortunately for the cause of reason Dembski has been able to make a career out of dressing this fallacy up to look like unimpeachable mathematics to the faithful.
I also find it funny that he tacitly admitted that the "designer" was comparable to gremlins. Funny little man, that Dembski.
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