Yujin Nagasawa

Maximal God: A New Defense of Perfect Being Theism

Yujin Nagasawa, Maximal God: A New Defense of Perfect Being Theism, Oxford University Press, 2017, 225pp., $60.00, ISBN 9780198758686.

Reviewed byJonathan L. Kvanvig, Washington University in St. Louis

(https://ndpr.nd.edu/news/maximal-god-a-new-defense-of-perfect-being-theism/)

We can automatically derive that it is possible that God exists because here God is understood as the being that has the maximal consistent set of knowledge, power, and benevolence. In other words, the maximal concept of God is by definition internally coherent because its components are mutually consistent (and internally coherent). This guarantees the possibility of the existence of God. (p. 204)

There are two problems with this maneuver, however. The first is the rather astonishing claim that consistency guarantees possibility. It doesn't. That's the lesson revealed by a posteriori necessities, claims that have denials that are logically consistent. One might try to restrict the inference to the a priori realm alone, but that doesn't help: lots of a priori philosophical theses are necessarily true if true at all, but remain subjects of substantive dispute precisely because both the thesis and its negation are logically consistent. Perhaps the inconsistency is such a deep one that we haven't seen it yet, but that's a hope rather than an argument. Moreover, since the converse of this inference is trustworthy (logical consistency follows from metaphysical possibility), endorsing this inference gives us an equivalence between consistency and possibility that arguably flouts Gödel's second incompleteness theorem.

The other problem with this defense of the ontological argument threatens to undermine the advantages provided by a top-down approach. For recall that the ontological argument depends on a further great-making property the possession of which can generate an inference from possible existence to necessary existence. Nagasawa relies on the version of the argument found in Alvin Plantinga's The Nature of Necessity, but central to Plantinga's approach is a bottom-up strategy, first identifying great-making properties that have intrinsic maxima and then deriving that God is an omni-being. Then, existence itself, or something involving it, is also taken to be great-making, with necessary existence being the maximum value possible. (My preferred way of expressing this idea is to talk about possible beings that have maximally fragile existence, where any change to a world in which they exist results in a world where they don't exist; then define durability as the capacity to continue to exist despite changes, with maximal durability implying necessary existence.) So, God is not only an omni-being, but also necessarily existent if possible.

...Basically I put this to remind me that everybody can have an opinion. Especially about god!