Behe, positive arguments, and negative arguments

If you've been following the posts at Panda's Thumb and other pro-science web establishments lately, you've seen a lot of criticism of Behe's testimony at the Dover trial. You will probably see more, as more of the transcripts become available. It's not so much a matter of piling on as it is a matter of the transcripts having so many different bad points to comment on. It's like a really bad blog article, but one that took place over three solid days of testimony.

This installment in the increasing body of work addressing Behe's substandard arguments will examine some of the things that he said on the stand about there being positive arguments for intelligent design. The material that I will be commenting on can be found during his direct testimony. The transcript is available in pdf format here.

There are two separate, relevant quotes. I'll provide them first, then comment on them. The first brief exchange is found on page 86. The questioner is Mr. Muise of the Thomas Moore Law Center. The answer is from Behe:

Q. Do you have an opinion as to whether intelligent design posits a positive argument for design?

A. Yes, I do.

Q. What is that opinion?

A. Yes, it does.

The second quote is a bit longer. It begins on page 90, and continues on 91:

Q. Now I want to review with you the intelligent design argument. Have you prepared a slide for this?

A. Yes, I have. On the next slide is a short summary of the intelligent design argument. The first point is that, we infer design when we see that parts appear to be arranged for a purpose. The second point is that the strength of the inference, how confident we are in it, is quantitative. The more parts that are arranged, and the more intricately they interact, the stronger is our confidence in design. The third point is that the appearance of design in aspects of biology is overwhelming.

The fourth point then is that, since nothing other than an intelligent cause has been demonstrated to be able to yield such a strong appearance of design, Darwinian claims notwithstanding, the conclusion that the design seen in life is real design is rationally justified.

Although Behe claimed that ID makes a positive argument, his summary of "the intelligent design argument" is fundamentally a negative argument. That is, inferring design is justified due to a lack of evidence for natural causes rather than as a necessary inferrence from the evidence. This becomes obvious here:

...since nothing other than an intelligent cause has been demonstrated to be able to yield such a strong appearance of design, Darwinian claims notwithstanding, the conclusion that the design seen in life is real design is rationally justified. [emphasis added]

That's not only a negative argument, it's two separate negative arguments. Concluding design is justified, according to Behe, because (a) no natural cause has (in Behe's unhumble opinion) been shown to be capable of creating the appearance of design; and because (b) the explanations offered by modern evolutionary theory are not sufficient (again in his unhumble opinion) to qualify as a natural cause capable of explaining the appearance of design.

Perhaps someday someone will make a positive argument for design. The argument made by Behe, however, was not (his testimony of a few minutes earlier notwithstanding).