Saturday, December 09, 2006

Fine-Tuning: The New Creationist Strategy

That's the topic of my latest post at Ezra's blog. The occasion is Sahotra Sarkar's article in the American Prospect on the move towards fine-tuning arguments. The second half of the post is the following argument, which uses the possibility of dualism against fine-tuning. I'm curious whether I've presented it in a way that non-philosophers will be able to understand.

In this response I'm assuming that what really strikes us as miraculous about our universe and provides the force behind fine-tuning arguments is the presence of minds. A universe with mindless life (maybe, a bunch of bacteria) wouldn't count as especially different from a universe with no life at all.

Now suppose dualism -- the view that minds are non-physical -- might have been true. I'm not asking you to suppose that dualism actually is true, but only that there's an alternate way things could've been, perhaps very different from the way things actually are, in which dualism is true. If the non-physical minds that dualists talk about might have existed, there's a variety of different possible psychophysical laws (laws governing how minds are attached to physical objects) which could have obtained. Even if we had different physical laws which don't allow for the large-scale physical phenomena that support minds in our universe, we could've also had different psychophysical laws which allow other sorts of physical matter to have minds.

The resulting picture makes the existence of minds seem like a far less miraculous thing, and eliminates the impulse to posit a Creator who set things up just right. Sure, it's kind of interesting that our universe is one in which the physical laws do so much work in making minds possible. But there's a huge variety of other possible arrangements of laws -- in particular, arrangements involving psychophysical laws which allow for an abundance of minds -- that would do the same thing. So there's no reason to think our universe really is fine-tuned by a divine creator after all.

5 comments:

Josh Brown said...

Neil--

This is an interesting argument--I'm actually working on a paper that makes a related argument: dualists (and so most traditional theists) can't rely on the fine-tuning argument to provide justification for theistic belief (for something like the reasons you lay out in the second paragraph).

This is a more limited conclusion than Sarkar comes to, since he takes the possibility of dualism to undermine fine-tuning altogether. I've got a few worries about Sarkar's version. (These are just quick thoughts and might not pan out.) The argument is slightly problematic if it's turning on metaphysical possibility, since many (most?) philosophers think that whichever of dualism or physicalism is true is true necessarily. Thus, if the actual world is physicalist, those dualist worlds are impossible.

A more substanive worry. Sarkar's version of the argument seems to legitimate a fine-tuning argument to the conclusion: either God exists or dualism is possible. It'd be weird if fine-tuning were able to force us to reject one of atheism and necessary physicalism. (That's not a diagnosis, of course--just a worry.)

I suppose I should go read the original post and get cracking on my paper.

--Josh

(p.s.--sorry we didn't get a chance to grab a beer while you were in town!)

Neil Sinhababu said...

Hi, Josh! good to see you here. The first thing to say is that the blockquoted argument is from me and not Sahotra Sarkar. I don't know if Sahotra accepts the possibility of dualism.

I didn't know that so many people tied actual physicalism to necessary physicalism. I remember that Braddon-Mitchell was worrying a lot about how to deal with cases where physicalism was actual but not necessary, but that might not have been a response to anyone in particular.

In regards to your more substantive worry, what strikes you as weird strikes me as nifty.

Sorry about missing you again in Ann Arbor. It's not unlikely that I'll be up there sometime next semester, so we may be able to finally hang out.

Scott K said...

Even though your current post is focused on one specific aspect of your discussion on Ezra's blog, I wanted to address the other aspect that you mentioned as well. You say that the most powerful argument you can think of against fine-tuning arguments is the problem of evil, but I think that argument is somewhat slippery since you would have to define evil in order to postulate that there is a "problem". I think it is too easy to develop counterfactuals ad nauseum to debate what is "evil" or even "more evil".

Now, to address the argument that you make in this post, I don't know if the fine-tuning argument strikes me as a very convincing argument because of the fact that the person/mind making the fine-tuning argument depends on the fact that the "fine-tuned" variables are as they are. There is no way to know if there were alternate realities or worlds where there might be different "fine-tuned" variables. I think that there is too much of a conflation of "philosophical necessity" and "physical necessity"... the theories, mathematics, and, yes, "fine-tuned" variables are developed to fit the world that we see so that we can form laws, theories, and make predictions. The mathematical description itself is always valid, but that does not necessarily mean that it will describe physical reality (or, for that matter, that it won't describe ANY physical reality).

I won't really address the dualism argument specifically, for the simple reason that I never really felt comfortable getting too deep into arguments related to dualism. So much of it, at least in my mind, boils down to how one defines "mind" and "body" and I never really found a satisfactory description that was not based on convenience (i.e., the arguments that a dualist makes essentially pre-determine his/her definition of the duality).

Not a philosophy specialist of any sort myself, my degree is in nuclear engineering, but I have read plenty of philosophy and enjoy it, so I don't know if I qualify as a "non-philosopher"...

Anonymous said...

Neil,
You said:
>>I'm assuming that what really strikes us as miraculous about our universe and provides the force behind fine-tuning arguments is the presence of minds.>>

I'm not sure what you're trying to say. The vast majority of fine tuning arguments center on physical constants (being set up just right for the existence of rational creatures like us, whether or not dualism is true). I have seen a COUPLE arguments for God's existence from the truth of dualism; the articles first argue for dualism, and then argue how dualism is antecedently more probable on theism than atheism.


>>Sure, it's kind of interesting that our universe is one in which the physical laws do so much work in making minds possible. But there's a huge variety of other possible arrangements of laws -- in particular, arrangements involving psychophysical laws which allow for an abundance of minds -- that would do the same thing.>>

Take the possible worlds in which dualism is true; a large fraction of these worlds are such that the psychophysical and psychological laws do not allow for creatures like us. They are worlds in which minds are only acted upon by bodies, worlds in which there are minds that aren't attached to bodies, worlds in which minds are attached to bodies in really weird ways (I will to raise my arm, but instead wet my pants), worlds in which minds are only attached to rocks, worlds in which mental properties cause atypical other mental properties (pain causes a desire for bananas), etc.

These are worlds that are not antecedently probable on theism; why would God want such a world? God doesn't just want minds; God wants certain kinds of minds; rational minds that can interact with each other and him, enter into loving relationships, etc. The creatures in these aberrant dualist worlds can't interact very well, or enter into relationships with one another and God, or be rational, etc.

So suppose dualism is true in this world; the fact that we are in a world that is in a small subset of all the possible (but undesirable, from God's perspective) dualist worlds strongly motivates a fine-tuning argument. Furthermore, the hypothesis of dualism (with its extra 'nomological danglers' that have to be arranged just right) is antecedently much more probable on theism than atheism.

So I really don't see how this 'possibility of dualism' argument is meant to defuse fine-tuning arguments. Many theists who are physicalists still advance fine-tuning arguments. They talk about how the values of physical constants are fortuitous, and give evidential support to the hypothesis of theism.

Neil Sinhababu said...

Scott, one of the standard responses to the fine tuning argument is that it works as an argument for some kind of multiple-universe view just as well as it works for the existence of God. I'm not 100% sure what the "alternate realities" point you're making is, but this could be a way of fleshing it out.

The point about weird mind-body combinations is an interesting one I hadn't considered, anonymous. I'm a little worried, though, that it might put some pressure back on the problem of evil. I don't think the theist wants to get too embroiled in a debate about exactly which mind-body combinations are better and thus more likely to be chosen by God. There's enough bad stuff going on in our world -- and enough failures of the mind (akratic drug abusers, various irrational people etc.) that the world doesn't look like one that a perfect being would create.