After considering arguments for the existence of God, Sobel has a brief interlude on the divine attributes, before going on to arguments against the existence of God. Chapter 9 concerns omnipotence and the famous Stone Paradox. Sobel defines omnipotence (roughly) as the ability to do anything that can be done. (He improves this basic definition in a few ways, but these need not concern us.) The Stone Paradox, Sobel rightly recognizes, is no real problem for omnipotence as such, for if a being can do anything that can be done, then that being can take away some of the powers it has, just as I can take away some of the powers that I have. As a result, there is no problem with an omnipotent being creating a stone it can't lift; it is simply that it must lay aside its omnipotence in the process. However, as this analysis shows, essential omnipotence is something else altogether, and this points to a more general problem: the God of the religious tradition has essential properties (in fact, it is most common, historically, for theologians to hold that he has all of his properties essentially). But then there are things I can do that God can't, such as making myself less knowledgeable. (Of course, God could make me less knowledgeable; what he couldn't do is make himself less knowledgeable.) Sobel comes up with a proposal for a coherent understanding of the feature the theologians want to attribute to God, but denies that this feature is properly described as 'omnipotence'. In this post I will discuss Sobel's proposal. In the next post, I will make a proposal of my own, and argue that it is sensible to call the feature I identify 'omnipotence.'
Sobel says that although nothing could be essentially omnipotent, a being could possess a feature Sobel calls 'only necessarily self-limited power' (ONSLIP). This is the property of being such that:
[one is] capable of each task t that it is logically possible that some being should do, which is such that (i) for each attribute, if any, that x has essentially, x's performing t is consistent with its having this attribute ... and (ii) if x has necessary everlasting existence, then performing t is consistent with its continuing to exist. (p. 365)
In other words, God's power is limited only by God's own nature. This is, I think, the sort of thing the theologians have in mind. However, as Sobel points out, a being might have this feature and not be anything like omnipotent. To use his example, a being might be "essentially incapable of creating something from nothing" (ibid.), and so be an ONSLIP without having that power. So Sobel is right that the property of being an ONSLIP ought not to be called 'omnipotence' (or 'almightiness'). I wonder, however, if perhaps we might get an omnipotence "worth the name" by specifying the sorts of attributes the being can have essentially. For instance, an ONSLIP who essentially possesses all positive properties (if we can get a decent understanding of 'positive' in this context) is not going to seem limited to us in the way an ONSLIP who is essentially incapable of creating something from nothing does.
[cross-posted at blog.kennypearce.net]