1. I didn't concede this, I announced it as my long-held position [see, e.g., this article about a talk I gave at Dartmouth three years ago; scroll down to the end].

I told Sahotra as much in extensive e-mail correspondence in the months leading up to the debate, and in a long conversation over several pitchers of Shiner Bock at an Austin bar the night before the event. So, using crushing logic and evidence during the debate itself, Sahotra had to wring from me (not) the very position about ID and public education that I've always held, and told him I would strongly advocate during our public exchange (which I did).

2. The proposition for the debate was NOT "Should Intelligent Design Be Taught in Public Schools?" If it had been, I wouldn't have accepted the invitation from the Undergraduate Philosophy Association. Hard to have a debate when both parties agree on the answer.

To Have a Debate, Find A Disagreement

Rather, the proposition at issue was this:

Can the evolution of life on Earth be explained by purely natural processes?

Now, I realize that under the rules of normal English usage, that sentence actually scans as

Should intelligent design be taught in public schools?

-- but, just for fun, let's consider its recondite interpretation, namely,

Can the evolution of life on Earth be explained by purely natural processes?

To that, I answered No, and argued that the naturalistic program of explanation hasn't even come close to satisfying its claims about explanatory sufficiency for events such as the origin of life, or even the origin of RNA.

Sahotra didn't disagree, or, to put it another way, there is no room for disagreement, if one wants to know the actual natural processes responsible for key events in the history of life. Questions like the origin of RNA, the origin of life, the origin of "orphan genes," and the other puzzles I mentioned (e.g., the non-homology of developmental pathways for anatomical structures such as the vertebrate gut -- see tomorrow's post) are open research problems. If Sahotra knew the answers, he didn't say; nor did Bill Wimsatt; nor did the two biologists on the faculty panel; nor did anyone in the very feisty, overflow audience. And that's because nobody knows.

The interesting question, then, turns out to be So what should science do differently, given the unsolved problems of the naturalistic program? Here, I argued that methodological naturalism, if held as an a priori principle -- that is, either find the natural [physical] cause or keep looking for the natural cause -- was a stultifying 19th-century doctrine, much beloved by naive philosophical naturalists (who use it to domesticate their opponents, while appearing to be asking only for testability, et cetera), but unworthy of science as open-ended enterprise.

Methodological Naturalism Held Axiomatically is Rock Pile Dumb

It is -- and Sahotra (smart and shrewd indeed) knows this. Indeed, skepticism about impregnable or a priori (come what may) naturalism is one of the major arguments of his forthcoming book on ID. I like simplicity, much to Amanda Marcotte's annoyance. Sorry to be so pedestrian again, Amanda, but here's an easy way to discover if one holds to methodological naturalism as an a priori or necessary principle:

Ask oneself a simple question. Suppose life actually were designed by a nonhuman intelligence -- would methodological naturalism allow us to discover that? If the answer is no, then methodological naturalism hinders scientific discovery and dictates the shape of reality as thoroughly as philosophical naturalism. If the answer is yes, then methodological naturalism is superfluous and says nothing more than that science should be empirical and testable.

That's drawn from my chapter with Marcus Ross in this new book.

And guess what? Sahotra agrees with this point. The only kind of naturalism worth holding, he argues, would be contingent, vulnerable to the challenges of experience. In other words, naturalism -- the doctrine of the ultimate sufficiency of autonomous physical causes to explain the world -- might be false, given the right evidence. Thus, even deeply-entrenched principles such as methodological naturalism could be overturned by experience, not least because, in the history of science (as Sahotra documents in Chapter One of his new book), they have been overturned. A few minutes into his opening presentation during the debate, Sahotra stressed this point. Naturalism held axiomatically would hinder the freedom of science.

But Intelligent Design Isn't Even in the Game Yet

So Sahotra continues his argument. Intelligent design theorists have put nothing on the table, he argues, other than a handful of minor problems for current evolutionary theory. Naturalism is entitled to stay just where it is as a regulative principle until such time as ID matures as a genuine theoretical competitor, which (says Sahotra) will almost certainly be never.

Well, those are terms for the competition that any ID theorist should readily accept. Axiomatic methodological naturalism (natural [physical] causes only, come what may) is an inquiry-killer. Contingent naturalism is not. Over more pitchers of Shiner Bock after the debate, Sahotra repeated to me that he held no metaphysical certainties, and would be willing to consider any good case for design, as long as the evidence was forthcoming. He doubted that any would be, but that was a different matter.

Make your case for design. That's a fair deal. All that any ID theorist could ask is to have his or her case evaluated on its merits, in light of the evidence. And that's why axiomatic methodological naturalism is wrong, and so profoundly inimical to the spirit of science as an open-ended search. Because the doctrine sets up the following hopeless situation for any investigator:

A. Find evidence for intelligent design, if any exists.

B. Whatever you find won't matter. Science allows natural causes only.

Sahotra endorses A. Not B.

For Tomorrow's Lesson

During the debate, Sahotra painted a picture of evolutionary theory as a program that has gone from success to success over its nearly 150 years of life. Tomorrow, I want to take up some of those successes, if one can really call them that.