Thursday, June 26, 2008

Intelligent Design Interview, Part 3

Here's part three of my interview with Dr. William Dembski.

RV. In your book Intelligent Design: The Bridge Between Science and Theology, you address a number of common objections to Intelligent Design (ID) including the criticism that design is simply an "anthropic coincidence." What is meant by this and what is your response?

DEMBSKI. In answering this question, let me start with an illustration. You have a forest and you shoot an arrow into the forest and you hit somebody. Now, what accounts for that arrow hitting somebody? One possibility is that the forest is just populated with numerous people lurking about, and if you shoot an arrow at random there's a pretty good chance of hitting somebody. Another explanation is that you took aim at the person and you nailed him.

How do we distinguish those two stories? If you're going with the chance explanation, the first explanation, you're going to want some independent evidence that there are other people in the forest. It's not enough just to say, well, there are probably millions of people in that forest. I've never seen any of them, just the person that I hit, but I'm going to assume that there were millions of people in the forest and that's enough to confirm the chance explanation. Unfortunately, that doesn't cut it. If you're going to allow yourself that move, then really you can explain anything by chance--what I call the "chance of the gaps," which is as bad as the god of the gaps. So you need independent evidence, namely, clear evidence that there were other people in the forest who might have been hit with the arrow.

The analogy with the anthropic coincidence is that the world is really a much larger place than our best observational physics seems to tell us. When you look simply at the known physical universe, it's not that big a place. It turns out that the known physical universe cannot run through even a small fraction of all possible proteins. You've got a universe that seems to be very limited. If you're going to try and account for things happening as massive thermodynamic accidents or quantum fluctuations, something that's vastly improbable, if you're going to try to make sense out of that, you're typically going to have to appeal to a much bigger universe--a place where you've got much more time, energy, mass, and space, than there appears to be on the basis of our observational physics.

So where it is all this additional stuff? We don't have any observational evidence for it. What we do have are theories that could indicate there might be other stuff out there, but there's no independent evidence to support those theories--the theories far outstrip our empirical resources. So, with these sorts of selection effects or appeals to a lot more probabilistic resources than we have observational evidence for, there seems to be a fundamental fallacy.

RV. Another objection you address in Intelligent Design is dysteleology. What is the charge and how do you address it?

DEMBSKI. The "dys" prefix, as in a dysfunctional family, indicates that something has gone awry. The idea is that there is a lot of bad or misshapen design in the world, especially in biology. Often when I give lectures on ID, people will go through a laundry list of things that are supposedly wrong with the human body: an inverted retina leading to blind spots. I'm asked why do we have back trouble? why are we subject to choking? why do we have vestigial organs? And so forth. The first thing you have to get on the table is that the design question holds irrespective of any other features that we put on top of design. Questions such as is it beautiful design, is it morally good design, is it competent or incompetent design? All these are really subsidiary questions. The main question is, Are we dealing with design at all? A torture chamber is designed. It's not designed for a good purpose.

Often the way the dialectic runs is, well, really when you're talking design, you're talking about the Christian God. The Christian God is good and wouldn't have made any imperfect designs, but we see all these imperfect designs, therefore the design can't be real and there is no design at all. But that logic just doesn't hold up. For one thing, I don't want to give people that much free play with Christian theology. Who's to say what is good and what is not? That's the problem that we've dealt with since the garden of Eden. We ate this fruit of the knowledge of good and evil, but we really don't know what's good and what's evil at times.

RV. It seems as though the dysteleology criticism takes a jump ahead instead of stopping and saying, yes, we agree this is designed, but we don't think it's designed optimally so let's bring up some objections. It seems the critics don't stop and say they agree it's designed.

DEMBSKI. Yes. It moves beyond that and tries to short circuit the design because any designer that could have done it (namely the "Big G" of Christianity) wouldn't have done it that way and therefore it couldn't be designed. You've got to just bring it back to the design question itself.

There are various ways of addressing the dysteleology question further. One thing to keep in mind is that there are all sorts of designs that we deal with in nature and in biology. There's exquisite design. You look at something like the bacterial flagella. This is a little motor-driven propeller on the backs of certain bacteria. A professor at Harvard named Howard Berg called this the most efficient machine in the universe and a marvel of bioengineering.

For other biological systems, however, the design characteristics may not hit you over the head so obviously. But if the design of a biological system is in doubt, it's not enough to say, "I would have designed it that way." Just because you can imagine how you might have designed it differently doesn't mean that when you do design it differently and insert it into a biological system that it would actually function better. These systems tend to be tightly integrated with other systems so one change can affect other changes. I don't know once instance in biology where the claims that "this could have been designed better" has actually been addressed empirically. It ends up not being a scientific claim at all.

One of the things I often say, when I'm lecturing on these topics, is that unlike engineers who know how difficult it is to build things that work, evolutionary biologists don't have that appreciation. They can just imagine how things could have worked and they're off and running. Evolutionary biology journals are filled with wishful speculations. Engineers can't afford that luxury.

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