Thursday, August 4, 2011

Can abiogenesis be falsified?

Liberal Christian scholar, jayman777 asks:

I’m not saying a mostly lifeless universe is, by itself, a strong argument against naturalism. It would be one argument among many. But, if you are going to hypothesize that life originated on Earth through natural means, then you will have to explain why there is no life on other earth-like planets, if that turns out to be the case. You could say it is extremely unlikely that life will arise even with earth-like conditions but then we’d have to ask what evidence you have for that claim. Perhaps you are just assuming that’s the case to save your pet theory. Can your theory of abiogenesis be falsified?
As far as I know astrobiologists have no idea what the chances of life are, so odds are their predictions will be wrong in any event and probably because they were framed as speculations anyhow. We have no prototype original replicator and so have no way of assessing the actual odds of life emerging anywhere. And if we had that replicator, then who cares about life on other planets? We would have already basically proven abiogenesis works at that point. Although I suppose one of the criteria for assessing whether or not it would be the proto-replicator would be that its construction was within the actual realms of chance and the molecular lottery that the vastness of the universe presents.

Anyway finding lots of life on other planets, or if we find “too much” life might imply intelligent design. Perhaps if we make breakthroughs in understanding abiogenesis, and find lots of life teeming worlds above the threshold of what we expect, that might mean aliens or gods have seeded the galaxy or something.

So it is a little bizarre to see the idea that not finding life on other planets counts against naturalism. It’s a molecular lottery to begin with *in principle*, and it’s a bit like being baffled that other people didn’t win the million dollars just because you did. Would that refute the lottery? Falsification is a bit of a red herring in that particular regard.

We should also compare the naturalistic hypothesis with a competitor theistic hypothesis on balance. The Christian theistic hypothesis (short of loading it with ad hoc assumptions to make it fit reality) predicts that a loving creator god would be intimately and overtly involved with its creation. There would be no problem of divine hiddeness, argument from religious confusion and unbelief, no argument from evil, prayer studies wouldn’t even be necessary to show that they were answered regularly, etc. These all serve as the ordinary indicators that such a god simply doesn’t exist.

If we are allowed to be incredulous about abiogenesis because science hasn’t shown us the mechanism, why are we not allowed to be equally incredulous about special creation? Have theologians shown us *that* magical mechanism? Where is the epistemic fairness?

And that’s just mechanism. What about comparing the plausibility of the ontology of the philosopher’s god to the ontology of a hypothetical proto-replicator? We know that molecules can combine into all sorts of things and we know that that sort of thing is going on all over the universe. For all we know, why wouldn’t a chance molecule get stuck in the bare physical constitution required for assimilating other atoms and/or molecules and making copies?

On the other hand, we have god as some kind of immaterial entity. Something without height, length, width, depth, location or any other physical characteristic. And what the heck is that exactly? Sounds like philosophers have just tossed out all the existency things about a thing and kept the label for show.

So to sum up:

1. Scientists are in no position to make accurate predictions at this point. We can’t solve the Drake equation, etc. Don’t take every sensational headline seriously.

2. Finding a lot of life in the universe might not help the naturalistic hypothesis.

3. Naturalistic abiogenesis is expected to be exceptionally rare in principle whereas a loving god is expected to show up and actually act like it.

3B. We could toss this in here that the primitive Bible cosmology predicts a relatively small snow globe universe where god is magically in charge of all the forces of nature and instead we find a ginormous universe that would be *needed* (not just accommodated) for a molecular lottery to play out. (this point is for the conservatives, but you do basically admit that’s what is in the Bible, even if you don’t take it seriously.)

4. We may not understand abiogenesis, but theologians can’t be said to be ahead of the game in terms of proving that god has creative powers.

5. We know that complex physical constitutions of molecules are possible, but “immaterial” things have not been shown to even make coherent sense as a hypothesis, nor is there any way even *in principle* to confirm that immaterial things actually exist given their um, "characteristics" or lack thereof.

And to end in the spirit of things as presented, what would count as the closest thing to falsification of naturalism on this point would probably be if the scientific world collectively gave up on exploring the issue because all they came up with were dead ends. But that’s just not the case. They’re exploring the issue from a number of avenues (top down and bottom up) and as a lay person I don’t feel I’m in a position to call them fools for doing so. I’ve sampled some of the literature and it seems promising enough. There are lots of things about that level of reality that I didn’t know.

So, that wouldn’t be an absolute falsification, since they may just have failed to find the needle in the infinite hay stack, but again, not finding god behind the holy mountain didn’t very well falsify theism, did it? And I think theologians have collectively given up on that approach and stopped talking to burning bushes.

I will also say that abiogenesis, in my estimation, is probably the weakest evidential link in the overall case for naturalism. However, on balance, it still seems stronger than any argument for theism that I can think of.