Dr. James Dolezal kindly sent me a copy of his very recent book, God without Parts: Divine Simplicity and the Metaphysics of God's Absoluteness (Pickwick, 2011). Herewith, some quick notes and commentary based on a partial reading.
1. God is an absolute, or rather the absolute. That is a non-negotiable starting point for both of us. To uphold the divine absoluteness, however, it is necessary to think of God as ontologically simple, as devoid of metaphysical complexity and composition. For if God is absolute, then he cannot depend on anything else for his existence or nature. It follows that God cannot be an instance of his attributes but must be them; nor can he be an existent among existents: he must be his existence and existence itself. Indeed, God as absolute must be ipsum esse subsistens, self-subsisting Existence. These are hard sayings and sharp heads, Plantinga being one of them, find them incoherent. For details and a bit of a response to Plantinga, I refer you to my Stanford Encyclopedia article. Note also that an absolute cannot be lacking anything or in need of developing itself: it is, eternally, all that it can be. This implies that there is no act/potency distinction in God, no unrealized powers or potentialities. In the classical phrase, God is actus purus, pure act, wholly actual. Dolezal puts it very well when he writes, "The consideration of God as ipsum esse subsistens and actus purus is crucial for any confession of God's absolute existence." (214)
2. But to uphold the divine absoluteness, it is also necessary that God be libertarianly free in his production of creatures. For suppose there is something in the divine nature that necessitates God's creation. Then God would depend on the world to be himself and to be fully actual. He would need what is other than himself to actualize himself. This entanglement with the relative would compromise the divine absoluteness. God would need the world as much as the world needs God. Each would require the other to be what it is. (210)
3. So God must be both simple and free to be absolute. But it is very difficult to understand how a simple being could be free in the unconditional 'could have done otherwise' sense. If God is simple, then he is pure act in which case he is devoid of unrealized powers, potentialities or possibilities. To act freely, however is to act in such a way that one (unconditionally) could have done otherwise, which implies unrealized possibilities. Now Dolezal's view if I have understood him -- and he can correct me in the ComBox if I am wrong -- is that it is not only difficult to reconcile simplicity and freedom, but impossible for us, at least in our present state. "Though we discover strong reasons for confessing both simplicity and freedom in God, we cannot form an isomorphically adequate notion of how this is the case." (210) In footnote 55 on the same page, Dolezal brings up wave-particle duality: light behaves both like a particle and like a wave. We have good reason to believe that it is both despite the difficulty or impossibility of understanding how it could be both. On the basis of the quotation and the footnote I hope that Dolezal will forgive me for pinning the label 'mysterian' on him, at least with respect to the simplicity-freedom problem which is only one subproblem within the the divine simplicity constellation.
4. I grant that if we have good reason to believe that p is true, and good reason to believe that q is true, then we have good reason to believe that p and q are logically consistent (with each other) despite an absence of understanding as to how they could be mutually consistent. What is actual is possible whether or not one can render intelligible how it is possible. To give an example of my own, motion is actual, hence possible, despite my inability in the teeth of Zenonian considerations to understand how it is possible. Many similar examples could be given.
And so a mysterian move suggests itself: We are justified in maintaining both that God is simple and that God is free despite the fact that after protracted effort we cannot make logical sense of this conjunction. The fact that the conjunction -- God is simple & God is free -- appears to us, and perhaps even necessarily appears to us, given irremediable cognitive limitations on our part, to be or rather entail an explicit logical contradiction is not a good reason to reject the conjunction. The mysterian is not a dialetheist: he does not claim that there are true contradictions. Like the rest of us, the mysterian eschews them like the plague. His point is rather that a proposition's non-episodic and chronic seeming to be a contradiction does not suffice for its rejection. For it may well be that certain truths are inaccesible to us due to our mental limitations and defects, and that among these truths are some that appear to us only in the guise of contradictions, and must so appear.
Of course, Dolezal's mysterian move cannot be reasonably made unless the extant attempts (by Barry Miller, Eleonore Stump, Brian Davies, et al.) to reconcile simplicity and freedom are failures. Since I agree with Dolezal that they are, I grant him this.
5. So what are some possible questions/reservations?
First, if a (conjunctive) proposition's seeming, after careful and repeated scrutiny, to be or entail an explicit logical contradiction is not sufficient evidence of its being a contradiction, what would be? To put it another way, my inability to explain how it could be true both that p and that q does seem to be pretty good evidence that p and q are not both true. Now I said above that the actual is possible whether or not I can explain how it's possible. Granted, but if I cannot explain the how, doubt is cast on the actuality.
How adjudicate between these opposing lines of argument: A: Because X is actual, X is possible, whether or not anyone can explain how it is possible! B: Because no one can explain how it is possible, it is not possible, and therefore not actual!
Second, if all extant attempts to reconcile simplicity and freedom fail, it does not follow that there isn't a solution right over the horizon. How can a mysterian rule out the possibiity of a future solution? The mysterian seems committed to saying that it is impossible (at least in this life) that there be a solution. How can he be sure of this?
Third, if a proposition appears under careful scrutiny to be or entail a contradiction, then is there even a proposition before the mind? If you require for my salvation that I believe that God is one and God is three, what exactly are you demanding that I believe? Before I can affirm a proposition as true I must understand it, but how can I affirm as true a proposition that appears necessarily false? Such a 'proposition' is arguably not a proposition at all. (This requires development, of course . . . Richard Cartwright's Trinity paper will help you see what I am getting at.))