Joined: May 2002
Hello all. What follows is a brief essay (or rant if you prefer) about the claim that ID is an appeal to the best explanation, specifically within the framework of ID's supposed explanatory power. This is posed as an answer to the question, "what's the logical fallacy here?"
It's not so much a logical fallacy. It's just that they're plain wrong as far as explanatory power is concerned. To actually explain something, you not only need to give an account of why something happened, but why it should have happened and why it didn't happen differently. In other words, your theory should predict the observed outcome, or at least predict a set of possible outcomes (the smaller the better) that overlap what's observed. It's pretty safe to say that evolutionary biology predicts a much smaller set of possible outcomes than does ID, which itself predicts an infinite set of outcomes (which is to say that it predicts nothing at all). So the plain fact of the matter is that ID is not only fails to be the best explanation, but it fails to be any kind of explanation at all. Evolutionary biology on the other hand, while not only giving us a general explanation for the diversity and unity of living things, also gives us a research paradigm for explaining the exact genesis of specific structures and functions within living things. Note that this is something that ID doesn't even aspire to.
The hypocritical IDist retort to this is to claim that evolutionary biology predicts an infinite set of outcomes, and is thus not testable itself. Of course if this were really true, then the IC and SC arguments against evolution would not be logically tenable. These arguments fail because they don't match up to the facts (and in the case of SC, because it's an excercise in question begging). But they really can't have it both ways. They can't claim that IC or SC falsify evolution while simultaneously claiming that evolution isn't falsifiable.
The mere fact that they try to make these arguments shows that evolutionary biology is constrained by what it can predict, and therefore can explain not just why things are as we see them, but why they're not somehow wildy different. Consider for example if every species on Earth were morphologically and biochemically distinct. Darwinian evolution could certainly not explain that. Or what if there were only one species and there had always been only one species? Again, Darwinian evolution would be untenable. I often think that people are so used to the facts of nature as they are that they don't stop to think about situations that might make non-evolutionary accounts far superior. (I also think this is why biologists, who are more aware of the facts of nature than your average joe, have a particularly hard time not accepting evolution.) But in all of these cases, whether whether nature is like it is now or whether it's completely different, ID accounts for it either way by invoking the same uninformative explanation: The Designer wished it such.
Now it's not impossible to get explanatory power out of this. But in order to do so you have to ask why the designer wished it such. This is not an unreasonable demand, as IDists often claim it is. When we see some sort of putative designed human artifact, the first thing we want to know is what it's for. And implicit in this demand is knowing how and why a human would have built such a thing, because of course we don't expect humans to be able or willing to build just anything. In other words, the set of possible outcomes is limited when we assume human construction. If we can say what object X is for and why humans living in location Y would have built such a thing, then we've gone a long way towards explaining the genesis of object X. But what's really senseless is that the IDists not only don't want to engage in this sort of discourse, they even claim that it's unscientific!
Naturally, they have their reasons. Trying to bring the designer and its attributes into the discussion would force a few things. 1) They'd have to admit that it's all speculation. There's nothing wrong with that per se, because every scientific hypothesis starts out as being speculative, but it would raise the issue of the acutal testing of ID hypotheses, and the lack of data on the Designer would make this difficult. Furthermore, real world data can eliminate several popular Designer hypotheses if we insist on taking the scientific approach to ID. 2) The Big Tent philosophy, who's purpose is to allow any and every ID hypothesis (except maybe the Raelins) equal access, thus swelling the ranks. This is just a political strategy. 3) They'd have to start comparing ID to Darwinian evolution. As it is now, it's advantageous to be completely devoid of any theoretical basis, because it lets them sit back and take pot shots at Darwinian evolution without having to account for the so-called mysteries that they invoke with a model of their own. And surely there are other reasons, but it's not necessary to figure them all out. The important point is that they've chosen to uncouple the ID argument from the only thing that would actually give it some explanatory power, which is some actual considerations about what it is that's doing the design, how it's being done, why it's being done, when it was being done, etc., etc., etc...
The uncoupling of the ID argument with any considerations of the desiger is exactly what makes ID devoid of any exaplanatory power. In the absence of a real design hypothesis, ID cannot ever be a scientific theory. Instead it's just an argument, and the only point to the argument is to prove a designer, not actually to explain anything. And it's not even a very good argument. AFAICT, the ID argument has in remained essentially unchanged since Paley. It was logically unsound to begin with, as shown by Hume, and then Darwin came along and demonstrated why it's unreliable. Can anyone tell me what new and interesting explanations for the properties of living things that Paley or his followers were able to come up with?
Edited by theyeti on Nov. 26 2002,17:51