I’ve been looking forward to reading Elliott Sober’s paper “Intelligent Design Theory and the Supernatural — The ‘God or Extraterrestrials’ Reply”, because I had heard that in that paper he argues that ID is after all inherently supernatural, despite the attempts of ID proponents to formulate the doctrine of ID in such a way that it’s not inherently supernatural. (For what it’s worth, I think these attempts are successful — ID proponents can formulate the ID doctrine any way they like, and they can hence choose to formulate it in a way that the doctrine can come out true even if naturalism is true.) The “God or Extraterrestrials” part of the title refers to the idea that, if ID researchers discover that life on Earth was intelligently designed, we could attribute this to God, or we could attribute it to intelligent aliens that seeded life on earth (“directed panspermia”). 

Before having read the paper, I was trying to guess what Sober would argue. I didn’t expect him to give a Barbara Forrest-type argument, to the effect that ID proponents believe in the supernatural, and hence they’re just being disingenuous when they say that their doctrine isn’t inherently supernatural — Sober is a better philosopher than that. But I couldn’t come up with a much more plausible argument than that.

And indeed, Sober’s argument, while slightly more plausible, isn’t much more plausible. What Sober says is that if we believe some other theses in addition to the basic ID thesis, then we’ll end up being committed to the supernatural. Sober’s idea is that these other theses are supposed to be independently supported theses that we should find plausible. Here they are (sticking with Sober’s numbering from the key argument of the paper):

2. Some of the minds found in nature are irreducibly complex. 

4. Any mind in nature that designs and builds an irreducibly complex system is itself irreducibly complex.

6. The universe is finitely old. 

7. In nature, causes precede their effects.  

It would be an interesting result if the basic ID claim, in conjunction with these four theses, entailed that supernaturalism is true (even if these four theses aren’t in fact plausible). I don’t think Sober even establishes that result. I won’t argue that here; instead I just want to point out that I’m not convinced that any of these four theses is true.

First, I worry that talk of a “mind” being irreducibly complex is a category mistake. Behe’s notion of irreducible complexity applies to physical biological systems that have parts, but it’s not clear to me whether a mind is a physical biological system that has parts. (A brain certainly is, but Behe isn’t talking about a brain — his argument that a mind is irreducibly complex involves a picture with boxes labeled e.g. “Beliefs”, “Desires”, and “Intention”.)

Also, I’m not at all convinced that the universe is finitely old; I think this is just an open question in physics. I know that the Big Bang hypothesis implies that the universe is finitely old, but the Big Bang hypothesis comes out of classical general relativity, which doesn’t incorporate quantum effects. There are more sophisticated models, like Paul Steinhardt’s cyclic model, which are compatible with the universe having been in existence forever. 

And finally, I’m not convinced that causes precede their effects. There are models of general relativity where there are closed timelike curves, and the evidence doesn’t conclusively show that our universe doesn’t approximate such a model. It would certainly be surprising if life on Earth arose as a result of backwards time travel, but it would already be surprising if life on Earth were the product of an intelligent designer; the God hypotheses strikes me as about as plausible as the hypotheses that super-intelligent ancestors of ours will one day travel back in time to seed Earth. In other words, given that life on Earth is the product of an intelligent designer, I wouldn’t want to say that the doctrine of intelligent design is inherently supernatural; I’d be just as open to the idea that the doctrine of intelligent design is inherently postulating time travel.