Sunday, August 24, 2008

Open Theism and the Test for a Prophet

During my year at Notre Dame's Center for Philosophy of Religion, I'm going to be working on a book-length research project on open theism, a relatively new proposal for understanding divine providence that has gotten a lot of discussion over the last 15 years, especially in philosophy of religion and evangelical theology circles.

Roughly stated, open theism holds that divine providence is neither wholly meticulous (as it is in Calivinism, Thomism, or Molinism) nor wholly general (as it is in process theism). In other words, God has not efficaciously decreed every particular thing that happens (contra Calvinism, etc.) but has efficaciously decreed some particulars (contra process theism).

The current debate about open theism centers on four key issues: (1) its fidelity to Scripture, (2) the significance of its differences from the mainstream theological tradition, (3) its ramifications for religious practice, and (4) its core philosophical presuppositions, esp. creation ex nihilo, creaturely libertarian freedom, and the incompatibility of meticulous providence with creaturely libertarian freedom.

In this post I want to briefly comment on one challenge, nicely posed by philosopher Francis Beckwith in an article entitled "Limited Omniscience and the Test for a Prophet". Beckwith charges that open theism, which he inaccurately supposes to entail the idea that God has "limited omniscience", is incompatible with the Biblical test for prophecy given in Deuteronomy 18:22:
If what a prophet proclaims in the name of the LORD does not take place or come true, that is a message the LORD has not spoken. That prophet has spoken presumptuously. Do not be afraid of him.
Based on this verse, Beckwith develops an argument that runs, in its essentials, thus:
  1. Necessarily, if X speaks for God about the future, then X is correct.
  2. If open theism is correct, then it is possible that X speak for God about the future and be mistaken.
  3. Therefore, open theism is false.
This argument is clearly valid (that is, if the premises are both true, then the conclusion must also be true), but not, I think, sound (since it is not the case that both premises are true). The premise that I wish to challenge is the second one.

The rationale for premise (2) runs something like this: Proponents of open theism hold that creaturely free decisions cannot be infallibly known in advance. It is possible that the outcome of a prophecy depends upon creaturely free decisions. Therefore, it is possible that the outcome of a prophecy cannot be infallibly known in advance. Therefore, it is possible that God could inspire a prophet to declare categorically that some future event will happen and that event not happen.

This reasoning overlooks something, however. It overlooks the possibility that there might be some other necessary factor that would prevent God from inspiring any categorical prophecy that he couldn't be infallibly certain about. Plausibly, there is such a factor in God's essential nature, namely, God's concern for his own integrity. If so, then it is consistent with open theism to deny the possibility that a prophet might speak for God about the future and be mistaken on the grounds that, necessarily, if God couldn't be absolutely certain about the prophecy's coming true then he wouldn't have given the prophecy in the first place. With that, premise (2) fails.

All that I'm arguing right now is that the quick knock-down attempted by Beckwith is too quick. There is, of course, a lot more to be said on this issue, and it is not yet fully clear that open theism is consistent with everything the Bible has to say regarding prophecy. Further reflections, however, will have to wait for another time.

Saturday, August 16, 2008

Can There Be a Self-Mover? Aquinas on Act and Potency

My family and I are now living in South Bend, Indiana. We survived the move well enough, though unfortunately some of our furniture didn't. (The movers wrecked the baby's crib, broke all four of our floor lamps, and lost a box containing three of wall pictures. Next time we go U-Haul.)

Anyway, my first blog post in a long time concerns Aquinas' distinction between act and potency. More specifically, I'm concerned with Aquinas' claim, central to the first two of his "Five Ways" of proving God's existence, that

(1) Whatever is moved is moved by something else.

If this is right, then there can be no self-movers. In the Summa Contra Gentiles Aquinas presents three arguments for (1). None of these strike me as particularly convincing, but I want to focus for a bit on the third argument, which appeals to the act/potency distinction. Basically, Aquinas argues as follows:

(2) Nothing can be both in act and in potency in the same respect at the same time.
(3) If there were a self-mover, then something would be both in act and in potency in the same respect at the same time.
(4) There cannot be a self-mover.
(1) Whatever is moved is moved by something else.

While I accept the validity of this argument, I am doubtful of its soundness because I find it very hard to come up with interpretations of 'act' and 'potency' that make both (2) and (3) true.

My first thought was that 'act' means actuality and 'potency' possibility, such that for something to be in potency with respect to property F is for it to be possibly F. On that reading, however, premise (2) is false. Since actuality implies possibility, it is perfectly possible - indeed necessary - that if X is actually F at time T then X is possibly F at time T.

My next thought was to make premise (2) true by defining 'potency' as possibly but not actually. The problem is that now (3) is false. To see this imagine a hypothetical situation in which a self-mover M can move either to the left or to the right. Initially, M is in 'potency' (as we have defined it) with respect to both options. That is, both options are possible for M, but neither is at yet actual for M. Now suppose that M moves itself to the left. In that case, M ceases to be in 'potency' with respect to either option and is in 'act' with respect with to going to the left. All this seems perfectly consistent, which falsifies (3). Why? Because the shift from being in 'potency' w.r.t. going to the left and being in 'act' w.r.t. going to the left is diachronic. M is never in 'act' and in 'potency' in the same respect at the same time. This indicates that it is possible for the antecedent of (3) to be true while its consequent is false, which is sufficient to show that (3) is not a necessary truth.

My final thought was to interpret 'act' and 'potency' in a causal sense of active and passive, respectively. This plausibly renders (2) true, though the proponent of self-motion might object that it begs the question. But my main worry again is that (3) is false. Why can't self-motion be understood in terms of acting at T1 so that M's future self is F at T2? Aquinas' argument against self-motion only works if a self-mover would have to be both in 'act' and in 'potency' in the same respect at the same time. But I just don't see why the 'act' / 'potency' relation can't be understood diachronically rather than synchronically. Indeed, shouldn't the very act of self-motion shift the temporal index forward? If so, then (3) is false and with it falls one of Aquinas' arguments in favor of (1).