Here at the University of Saint Thomas Summer Seminar, (what a beautiful campus!), we’ve just completed our first week, the topic of which was the Fine Tuning argument for God’s existence. There were a lot of great presentations and comments pro and con, but I find myself mostly a Swinburne guy here. So I wrote a note to my colleagues here giving a bare-bones summary of his perspective. It is below the fold as a basis of further discussion or just for the record.
I * literally* can’t help reflecting back upon this first week of reflection on the fine-tuning argument. (Seriously, I tried not to, and I seem to be failing, since I’m still typing.)
There were a few things I thought bore repeating, even though they were either mentioned by me or someone else during the week. They are not original thoughts, but, rather, the ideas Swinburne has been defending for many years.
You can think of the FTA as either an Inference to the Best Explanation (IBE) or in Bayesian terms (with the prior probability being determined by simplicity considerations and the liklihood (E/T) being determined by explanatory power).
1. The Simplicity (Prior Probability) of Theism
Theism postulates, in its basic ontology, one entity with two properties (maybe one–“intentional power”–maybe three): power and knowledge, held in the simplest way (without limit (apart from logic)).
This “bare” theism, of course, and is ontologically sparse, as you can see.
It might be strange that there exists anything at all, but it shouldn’t be terribly strange that something exists. The only state of existence simpler would be one entity with one property (or maybe two) also held in the simplest way (with zero limit). You might think being a knower entails a few independent properties. I doubt that, but suppose it does. We are still talking about a single entity with a small cluster of properties (and it might be that the property of personhood is a single natural property with knowledge, power, and what you think those entail as *facets* of one natural property. So the prior might be low on any existence, but, on the idea that we assign priors on the basis of sparse ontology–which Swinburne argues from cases is what good science does–theisms prior shouldn’t be terribly low. It is bad practice to assign it low probability because it seems vaguely “weird.” Philosophers should have made peace with the weird long ago. 🙂
2. The Explanatory Power (Likelihood) of Theism
Being all-knowing, God will know what states of affairs are good (more generally, he’ll know the value of all states of affairs) ASSUMPTION: Some states of affairs are objectively better than others (at least along some dimensions of evaluation).
Being all powerful, nothing will deter him from the intrinsically motivating power of the good. (ASSUMPTION: A version of ethical “internalism” according to which for a person to see something as good is to give that person a pro tanto desire for it/pro tanto reason to seek it.)
***So a state of affairs has an expectation on theism to the extent that we see value in it. There are many goods and kinds of goods and they can’t all be realized at once, so it would be hard to anticipate in advance which goods God would bring about (though this provides God some reason to bring about all kinds of goods at some point (or always): theistic multiverse).
So to the extent we find value in a state of affairs (or in a state which it entails or makes probable) it is relatively unsurprising given theism. CAVEAT: What about evil? Virtue is perhaps the most valuable thing imaginable, and some of the greatest virtues: forgiveness, empathy, magnanimity, humility, courage, moderation, etc. logically entail some kind of suffering. Heroic virtue entails tragic suffering.
The universe we see with it’s beauty and ugliness, it’s tragic suffering and heroic virtue is a good (kind of) universe. So it is relatively unsurprising that such a universe exists, given theism.
3. The Complexity of Naturalism
A. Single Universe Naturalism (SNU)
SNU postulates, in its basic ontology, a very, very large but finite number of properties of a finite number of kinds, with properties of highly specific values (vary the language all you want, some of them are going to be highly specific)
B. Mult-Universe Naturalism (MUN)
MUN postulates, in its basic ontology…SNU^n stuff! A universe isn’t one thing, it’s many things taken together. A multi-verse isn’t one thing. It’s many things taken together. ASSUMPTION: The prior/intrinsic probability of a hypothesis should drop for every new entity and kind of entity postulated (in the *basic* ontology) and for every finite parameter (or for every property and property exemplificaiton).
4. The Explanatory Power of Naturalism
E/SNU = lower than we can really grasp
(i) MUNs actually proposed by scientists
E/MUN = varies from very low to not too low
(ii) Really robust (plenetudenous) MUN’s
E/MUN = 1
Which theory is better off depends on two things: 1. The ratio PrINTRINSIC(T):PrINTRINSIC(N), and the ration Pr(E/T):Pr(E/N)
Above, it was argued that BOTH are favorable to theism. I.e. that it predicts the data better, and that it has a higher intrinsic probability (do to much, much more sparse basic ontology).
Still, the liklihood ratios, IF the fine-tuning estimates are right–are going to favor theism (T) over SUN by such a large factor, that even a ridiculously uncharitable prior to theism is going to be utterly swamped. The differences are so large by some estimates, that if you gave theism a prior of 1 in 10^17 (1 over the number of estimated stars in the universe) theism would come out with a probability well over .99 (playing around in a spreadsheet with this, Ted Poston and I had a hard time believing how confirmatory this argument is, it was really surprising, though it shouldn’t have been).
MUN is not that much different. Even if you think the likelihood value is greater by three or four orders of magnitude, I think it will be weaker by many more orders of magnitude than that in the prior given that the fundamental ontology includes an actual infinite multitude of kinds and (continuum many) tokens of properties (which I don’t even think is logically possible, but that’s another argument, as is the issue that these entities are all clearly contingent beings).
This is only the barest summary of Swinburne’s _Existence of God_ off the top of my head and un-proof-read (charity!), but I thought it bore writing out in one spot in only about 1000 words.
I’ve posted this at Prosblogion for further discussion or just for the record.
Department of Philosophy