God and Necessity

by Brian Leftow

Brian Leftow offers a theory of the possible and the necessary in which God plays the chief role, and a new sort of argument for God's existence. It has become usual to say that a proposition is possible just in case it is true in some 'possible world' (roughly, some complete history a universe might have) and necessary just if it is true in all. Thus much discussion of possibility and necessity since the 1960s has focussed on the nature and existence (or not) of possible worlds. God and Necessity holds that there are no such things, nor any sort of abstract entity. It assigns the metaphysical 'work' such items usually do to God and events in God's mind, and reduces 'broadly logical' modalities to causal modalities, replacing possible worlds in the semantics of modal logic with God and His mental events. Leftow argues that theists are committed to theist modal theories, and that the merits of a theist modal theory provide an argument for God's existence. Historically, almost all
theist modal theories base all necessary truth on God's nature. Leftow he argues that necessary truths about possible creatures and kinds of creatures are due ultimately to God's unconstrained imagination and choice. On his theory, it is in no sense part of the nature of God that normal zebras have stripes (if that is a necessary truth). Stripy zebras are simply things God thought up, and they have the nature they do simply because that is how God thought of them. Thus Leftow's essay in metaphysics takes a half-step toward Descartes' view of modal truth, and presents a compelling theist theory of necessity and possibility.

Genres: Philosophy, Theology

592 pages, Paperback

First published September 6, 2012

Reviews

[Donald Linnemeyer · Rating 3 out of 5]

This is my first time reading modern analytic philosophy, and Leftow managed to keep my attention for most of the book, which is pretty impressive. I don't really have the patience for this sort of reading, but his writing was relatively down-to-earth and understandable, especially considering the topic.

As for his argument, there's plenty of good and interesting stuff in here, but I didn't ultimately buy off on his critique of Thomistic thought. Leftow ends up putting forth something with pretty much the same structure (God thinks up a set of ideas, then chooses out of those what to create), the main difference being Leftow's voluntarism. Where Aquinas (and plenty of others) claim that the divine ideas come inevitably out of God's nature - what Leftow calls deity theory - his alternative places the cause of the specific ideas themselves in an act of will, depending on God's nature itself only for a very general sense of causation. As Leftow says, "to locate my position, start at Aquinas and take a half-step toward Descartes."

The main objection I have is that Leftow's position never offers a compelling cause for God's specific ideas or why God chooses to actually create the ideas He ends up creating. He argues for the former out of some sense of "spontaneous imagination", a "wild card" creativity. This basically boils down to nothing: "if His nature did not determine what He thought up, nothing did." Leftow resorts to the same sort of approach for God's actually creation of specific ideas. He bases this on "preferences" which are equally causeless. God just has preferences, and they are what they are. There is no higher reason for them, beyond God's built-in ethical limitations.

Leftow claims this serves as a better approach than Thomism because it leaves God more free, not bound by some built-in sense of inevitability in His own nature. Besides, He claims that Thomism resorts to the same tactics - when asked why specific ideas and attributes flow from God's nature, they have no concrete answer. God's nature therefore only generally accounts for creation; you can't get anything specific from it.

It's this last point that I found least compelling. Why is it invalid to simply point to our creaturely limitations? It seems simpler to simply say that while we can't describe the specifics as to why God's nature entailed that there would be dogs or whales doesn't mean there isn't a connection. We may not have discovered it, and we may never discover it, but God knows that connection. Leftow seems to run into this problem, and instead of recognizing it as a great area of exploration for humanity, he sees a impenetrable fog and essentially gives up, seemingly claiming that because we can't reason through the connection, there is none, and so "nothing" caused these ideas and preference. His logic at times is obviously more nuanced than this, but it does seem to boil down to something in this ballpark. Pretty simplistic and rather unconvincing, especially given that his argument from freedom seems to be based on a context-less view of freedom instead of seeing freedom as the ability to act rightly or act in accordance with justice.

On the positive side, I did appreciate his tendency to downplay the important of the divine ideas in the two-step process of creation, referring to them at times more as divine powers, capabilities or creating things and not so much actual entities. I'd like to push this a step further, though, and get rid of them altogether, replacing them entirely with simply an implicit divine ability to think up and create other things than He did (Anselm talks in terms of implicit divine knowledge in His doctrine of the Word containing all words of creation, which is a good start). If we push the artist analogy, creation is a project, a singular goal to image Himself in a finite universe. God decides to do this, and all of creation (and history?) is a step-by-step accomplishing of that goal. Given this, it seems pointless to insert a step where God simply ponders countless ideas that He never ends up creating, that never end up serving any end toward that goal of creation. This seems to make God into a day-dreamer for a time rather than a focused creator. If God is infinitely wise, He would have no need to ponder alternative courses of action. He'd have implicit knowledge of all possibilities and He'd immediately, without any intervening steps, choose the best, wouldn't He? If analogies to human creativity hold at all, this seems inevitable.

Anyway, plenty of interesting stuff, and a lot more accessible than I was imagining. If you're interested in the more philosophical end of cosmology (why did God create what He created? how is creation the image of God?), it's worth working through, especially the first half.

[Christian]

Leftow spends the first half of the book setting up the position that he wants to refute. I got lost in the first half of the book, so I never really found out what he wanted to say.