Continuing to address a new Substack piece by James Croft where he objects to some of my comments on his debate with Stephen Meyer, today we turn to a hot topic: aliens!

He’s Not Saying It’s Aliens

In my article on the God hypothesis and the problem of background knowledge, I said that were Croft to apply his demand for background knowledge consistently, it would mean we couldn’t indirectly infer our way to non-divine alien entities either. Croft doesn’t concede this, but he does say there would be a “degree” of hampering from a lack of such knowledge:

How could someone responsibly construct a hypothesis that a new, non-human intelligent agent might exist? Does the lack of background knowledge that I’ve pointed to on the part of God also hamper attempts to abductively infer that aliens are the cause of some phenomenon, for instance? To some degree, it does — and of course it does.

He illustrates with an example: Suppose a crew lands on Mars and finds a perfectly spherical floating orb of unknown make and origin. If this crew had independent background knowledge of alien races with means and motive to build floating spheres,  this would make the inference to aliens stronger than if they didn’t. 

This is true! Trivially true, in fact. Neither Meyer nor any other ID-friendly philosopher would disagree with Croft that background knowledge can make a good inference to the best explanation better. But the question at hand is whether it’s always needed to make it good.

In this specific case, Croft happens to think that absent background knowledge, “Aliens!” would be a weakly justified hypothesis. Here, my mind immediately went to the scene in 2001: A Space Odyssey where moon colonists discover a monolith — not a floating sphere, but a grounded rectangular prism, which emits a high-pitched sound when the sun comes out:

The scene is shot and scored in a very ominous way, where the ominousness lies precisely in the sense that the monolith is, well, alien. And in fact, as the story unfolds, we learn that it is. 

Maybe for Croft, it wouldn’t be so ominous. But maybe it would. I would be curious to know if he thinks it’s analogous to his floating sphere or not. A more interesting question, though, would be to ask him what our Mars landers should conclude if they find, say, a cave wall displaying the digits of pi. Or perhaps a friendly garbage-collection robot, with a design unknown to any human designer on Earth at the time. Those sorts of discoveries would be much more analogous to what we observe as we examine human and animal bodies on a micro and macro scale — code, function, moving parts in service of a whole, and so on and so forth.

It’s the Things You Know…

But Croft believes he can say more. The inference to aliens behind the floating orb is weak, but “Meyer’s inference to God is even weaker [emphasis Croft’s].” He then gives a proof-of-concept argument based on the “background knowledge about human beings, evolution and astronomy” our Mars landers could still appeal to:

1. We know that intelligent life can evolve on particular kinds of planets, because we did.

2. We know that there are lots of potentially life-permitting planets in the universe, because we have found many of them, and we can tell from our understanding of astronomy and physics that there must be many more out there.

3. It is reasonable to conclude, given what we know about the evolution of life on our planet, that intelligent life may have evolved on one of these other worlds.

4. It is plausible, given what we know about humans and other animals, that such life would also want to create technologies (as we and other animals do), and also that they might want to contact other species.

5. Sufficiently advanced alien technologies might be inexplicable to us, just as the technologies we have today would be inexplicable to our ancestors were they to view them. And, therefore:

6. It is not unreasonable to postulate that this phenomenon (the floating orb) is a technology created by an alien intelligence.

The second half of this argument is good (hurray, agreement)! However, I find it ironic that Croft’s Premise 4 appeals to the creativity, drive, and, well, intelligence that we observe in ourselves to design things. He appears to believe this is a legitimate stepping stone on the way to aliens, but in his frame, it abruptly loses all legitimacy on the way to God. His Premise 5 also shows deference to things that might be beyond our ken from our currently limited human perspective, also wise! But are doctors and scientists likewise not still stymied by many mysteries within creation itself? Have there not been numerous times when they declared something “useless,” only to discover they’d been too hasty?

But of course, the really eyebrow-raising premise here is the first one: “We know that intelligent life can evolve on particular kinds of planets, because we did.” Is that a fact? Obviously, I’m not here to recap the entire debate over the evolution process, nor the origin of life process. The origin of life debate is especially heated, as Meyer shows in his latest book, and as other excellent scientists like Brian Miller and James Tour have done elsewhere. I won’t repeat their arguments (though I’ll link to just one article by Miller treating a critical review of Meyer’s book at length), but I will say it’s cheeky of Croft to simply help himself to this statement as his own Premise 1 in a hypothetical case for aliens, when it’s the very question at issue in the debate over the God hypothesis. If this is how he defines “background knowledge,” perhaps we simply have different standards for “knowledge”!

The extreme improbability that life would originate by chance is a good note on which to pause and pick up next time, as I address Croft’s more technical objections to Meyer’s Bayesian inference.