Wednesday, September 17, 2008

Am I Missing Something?

There's been quite a lot of flap over Nagel's recent article defending the teaching of intelligent design in public classrooms. Most commentators have chosen not to focus on the constitutional question--which is the real focus of the article--and instead focus on the defense he offers for the scientific respectability of intelligent design. I'm going to follow that lead.

Is Intelligent Design a scientific hypothesis, even if a very unlikely one? Depends upon what we mean by 'scientific hypothesis'. But I think that the most plausible definition of science entails that it soooooo obviously isn't. That this point has not been commonly made makes me suspect I'm missing something.

On the one hand, any claim is 'scientific' insofar as it is supported by evidence. Any reasoning process is scientific insofar as it allows itself to guided by this evidence. The next question is, What counts as evidence? On a broad definition, ANYTHING can count as evidence. If I'm wondering whether or not to believe in God, for example, I might turn to St. Anselm, and to Alvin Plantinga, and to Michael Martin, and then Richard Dawkins, and then to the authority of my grandmother, who says that there's a God and I respect her opinion, to the fact that the Church has been around for a long time and this seems to be some evidence for Divine protection, to the fact that the universe seems largely explicable in purely physical terms and I favor Okham's razor, and so on and on. When I am forming my own personal beliefs, if I am rational about it, I will weigh all this evidence (never mind how I compare them for strengths and weaknesses), and form a subjective probability of belief. Let's call this the Bayesian Theory of Science.

The Bayesian Theory of Science is not a very good one--or at least, it's not a very sufficient one. Because on a more plausible definition of science, some types of evidence are going to be ruled out of court, and for good reasons. In addition to a commitment to evidence, and a commitment to allow one's reason be guided by evidence, the upshot of the scientific enlightenment was to stipulate that every state of the universe is fully explicable from the facts of an earlier state (actually, there's no need to temporalize this: any state of the universe U is explicable in terms of another state of the universe U'.) Maybe this wasn't such a stipulation. Kant made a good case in arguing that we simply had to think this way. But in any case, that is the idea.

By this definition, ID obviously is not scientific, even if there is some non-scientific evidence for a strictly Bayesian thinker to consider in its favor. The major premise behind ID theory is that the state of the Universe LIFE is inexplicable in terms of the state of the universe NO LIFE. Some non-universe actor intervened at some point, and an intelligent one at that. But what sort of claim is this? Clearly, it's a claim that a miracle happened. ID is a miracle-theory. Miracles don't belong in science, even if there is some non-scientific evidence to consider for their presence. I don't get why this point hasn't been made (that I've seen). When Spinoza and Hume and Hobbes were writing their long tracks against miracles, it wasn't just to prove that there were no miracles. More importantly, it was to convince their compatriots that the very notion of a miracle was incompatible with the emerging scientific world-view. We don't need to prove that science contradicts the possibility of miracles, only that miracles and any scientific theory are inconsistent.

Consider a situation where the scientific community actually adopted the ID position: what would be left to do? There would be consensus that it was pointless to research anymore how something like a living organism could arrive out of amino acids in the early conditions likely to have obtained on a primordial earth. In other words, they would stop trying to explain the origin of life. I would submit that any hypothesis, if true, that would halt scientific inquiry is, by definition, nonscientific.

Consider finally the argument Nagel is most famous for: the irreducible nature of subjective consciousness. There's good evidence in favor of this hypothesis. Anyone who is conscious has access to this evidence. The presence of this evidence is pretty overwhelming. Many smart people are convinced that this evidence is strong enough to ground the conclusion that consciousness is non-explicable in physical terms. But Nagel's own conclusion was not that consciousness has some queer, scientific status. His conclusion was there could not be a science of consciousness, at least not until our conceptual frameworks radically and unforseeably changed.

UPDATE: You might notice that two of the responses linked to above are moderately complementary of Nagel's argument. I would like to point out that both are Bayesians (or at least almost).


  1. So, I'm not a defender of ID, per se, nor am I an expert on the subject, but I think you ARE missing something. Firstly, the definition of science you use is not, historically, 'the upshot of the scientific enlightenment.' Paradigmatic examples of 'scientific enlightenment' thinkers - Newton, Boyle, etc. - didn't buy it. In fact, Newton thought God had to periodically intervene supernaturally to set the planets back in their orbits and prevent them from falling into the sun! Most scientific enlightenment thinkers wouldn't have thought science had failed if there was an occasional miracle. The list you give is hardly representative, and none of those philosophers were respected scientists. On the other hand, many early modern scientists probably would have thought science was a failure if they learned that the universe was, under ordinary circumstances, indeterministic. Oops...

    Furthermore, it would be silly to say that believing in science means NOTHING can ever count as evidence of the activity of an intelligent agent (I've seen this compared to investigating a strange rock formation on another planet starting with instructions to conclude that it was naturally occurring no matter what you found).

    Based on my limited knowledge, it would seem that the most intellectually respectable proponent of ID is William Dembski who is a mathematician who wrote a book which I believe is published by Cambridge University Press as part of a series of monograms in mathematics. I believe the book is called 'The Design Inference.' The book is NOT about ID. It describes a mathematical model for the reasoning involved in determining whether an object (e.g. a strange rock dug up by an archaeologist) is the product of an intelligent agent. In separate writings Demski (who, let it be noted, believes in most of standard evolutionary theory) argues that the model leads to the conclusion that the Cambrian Explosion was engineered by an intelligent agent.

    Now, this is the most intellectually respectable version of ID I've come across, and it still may not be all that plausible as an argument (I haven't examined it in depth), but it sure seems like a scientific claim to me, and even if it's not a scientific claim, it is still an empirical claim that is best investigated by the methods scientists are accustomed to use.

  2. Hi Kenny,

    Let me avoid the issue of 'science.' Newton of course did think that God had to intervene in order to keep things moving, but he does so in absolutely regular and predictable ways...which is why the thesis is superfluous...

    As to the more relevant matter: I wanted it to be clear that we should distinguish between rational evidence, and scientific evidence. I'm sort of willing to accept a very broad, even subjective notion of rational evidence, but 'scientific' evidence is more constrained, and in the following way: whatever happens in nature happens for natural reasons. This itself of course is not a scientific claim, it is a rational one, and perhaps should be revoked for rational reasons (though I doubt it). So, even if ID were 'intellectually respectable,' it could never be scientifically respectable.

    Again, I revert to my comment in the post: to see that this is true, just assume that ID is true--what science is there left to do on the issue of the origin of life? And if we were convinced, wouldn't it be silly to keep searching for how life could emerge from inorganic material and processes? If we accept the framework of ID, we have to jettison science.

  3. "That this point has not been commonly made makes me suspect I'm missing something."
    You've just got to get out of the house more. ;-)

    "Scientific" in a broad sense, as in partaking of the common nature of scientific community dialog as well as the textbook definition.

    One should not use historic science as in "Newton said this or that." or "Darwin said this or that." because science has developed into a robust practical discipline during the intervening period. Rather one might explain in the framework of Collins' work and Kuhn's work how the arguments put forward by the Discovery Institute could not satisfy the requirements of any modern scientific society. You know the story of the Smithsonian sponsored journal for taxonomists...?

    The previous poster's remarks about being intellectually respectable is reference to the documentation placed in evidence at the Dover trial demonstrating versions of the textbook that were contradicted by testimony of Discovery Institute personnel.

    Much like the judge in the tobacco trials, Judge Jones in the Dover trial did not rule on the "science" of the argument. He ruled against the Intelligent Design people because they lied to him directly.

    Most of what Discovery Institute people have done in the last couple of years has been on evolutionary genetics. The same error in understanding how four and a half billion years is enough time to develop more than one alternative biologic mechanism has caused the logic of their enzyme evolution argument to fail.