Tuesday, January 15, 2013

Is there a cosmological argument from objective probability?

I am finding myself pulled to the idea that objective probabilities must always go back to objective tendencies. If so, then on pain of vicious regress, we must have a metaphysically necessary being (prima facie, perhaps an aggregate of multiple beings) which has objective tendencies that ultimately ground all objective probability. Such a being cannot be merely abstract as it is causally efficacious.

Moreover, I am inclined to think rational subjective probabilities are our attempt at modeling the relevant objective probabilities in the face of our ignorance. If so, then if one denies such a first cause, one cannot coherently engage in probabilistic reasoning about reality.

A lot of work is needed to work out a cosmological argument along these lines. I don't have it worked out. It's just an intuition based on a lot of thought about probability theory.


Kenny said...

This is an interesting line of thought. One of the things that's interesting about it is that things like 'the wavefunction of the universe' or the various quantum fields might be better candidates for the necessary being in the conclusion of the argument than a personal God. In particular, they might be better candidates than a libertarian-free God, for these entities from physics have quantifiable objective tendencies, they operate by a probabilistic mechanism, and hence are well-suited to give rise to objective probabilities in the world, whereas a libertarian-free God does not act by a probabilistic mechanism, and hence it is hard to see how his objective tendencies would give rise to precisely quantifiable objective probabilities. (This is assuming an agent-causal-type libertarianism; I suppose one could apply a Kane-type libertarian theory to God, and have some kind of probabilistic mechanism withing God.)

Alexander R Pruss said...

I am not sure that quantifiable probabilities are needed at the base for there to be quantifiable probabilities at the end. But that's a very good question.

Kenny said...

I'd be interested in seeing how you get from non-quantifiable objective tendencies to objective probabilities. However, even if it can be done, I would tend to think that the fact that the path from the objective tendencies of the necessary being to the objective probabilities we find in nature is more or less trivial with one of the physicsy candidates for a necessary being would be enough to make one of those candidates ceteris paribus preferable from the perspective of this particular argument. Of course, the thing to do is to show that other things are not, in fact, equal.

Alexander R Pruss said...

The problem is that the physicsy candidates will violate the intuition that radically different laws are possible.

Kenny said...

Well, yes, and classical theistic candidates violate the intuition that really awful worlds are possible. Is one result worse than the other?

Alexander R Pruss said...

I think so. :-)

But that said, all of this is speculation on an argument that may not ever get worked out...

mjm said...

Hello Alex,
I'm reading with interest your excellent treatment of Leibnizian Cosmological Arguments. I'm wondering if an advocate could thread the needle through van Inwagen's Dilemma a different way:

1) God does not create the actual world (an abstract entity).
2) God does not choose which world to actualize.
3) God chooses that some world, from a perhaps infinite set of equally suitable worlds, is
actualized (that is, his choice is an existential generalization: Let there be one, any of those,
meeting some set of design constraints).
4) Which world is actual is explained by:
a) the necessary truth that God chose to actualize some world meeting the constraints.
b) the results of intra-world causes, including undetermined events, some of which are the actions of free rational creatures.

All contingent truths are thereby explained, with each of the constituents participating. It is necessary that there be some world or other meeting the constraints (explained, indeed entailed, by God's decree). Which it turns out it be is explained by that choice, plus intra-world causes, and God's continuing effect on the course of universal history. That continuing effect is different from what it would have been if another world in the set had been actualized, but the cause itself would not have been: God necessarily wills the best ultimate outcome. When that single necessary trait hits any contingent world history, the best outcome ensues (in ways that differ world-side, not God-side, as the same heat would have melted any wax placed before it).

There is no "undischarged contingency": a necessary being, necessarily willing the same constraints, is required to answer "Why a world like this ?". It allows for creaturely
freedom, "secondary causes", it guarantees that any world meeting the constraints is one
of the best possible worlds, it is not committed to saying this is the best of all possible