Theism and Explanation - Appeared-to-Blogly

84 Theism and Explanation
eye. But neither of them knows this. Both help themselves to assumptions
about God’s goals and abilities. However, it is not enough to make
assumptions about these matters; one needs independent evidence that
these auxiliary assumptions are true. 20
Let me begin with what is correct about this response. It is surely right
to ask for independent evidence of the truth of the assumptions that are
being employed. I have insisted on this from the beginning. But as I argued
in Chapter 3 we are perfectly at liberty to make such assumptions and then
see what follows from them. This is precisely what it means to offer a theoretical
explanation, supported by abductive reasoning. So we are entitled to
posit the existence of a God having the requisite “goals and abilities” (to use
Sober’s terms) and then ask what we would expect to observe as a result. If
the explanandum is among the things we would expect to observe, given
this hypothesis, then we would have satisfi ed the second premise of Peirce’s
abductive schema (2.1.2). Of course, the conclusion of Peirce’s schema is a
modest one. At best, such reasoning only gives us reason to suspect that
the hypothesis is true; some kind of corroboration is required (7.1). And it
is here that Sober’s requirement (and my desideratum) of testability comes
into play (7.1).
But Sober thinks we cannot go even this far, that we cannot say what
would follow if the theistic hypothesis were true. And at this point I must
side with Gould against Sober. For Gould’s argument employs the rationality
principle that I have suggested lies at the heart of all intentional explanations.
It assumes that a divine agent will act rationally, in order to achieve
his goals. Gould rightly senses that this places some constraints, not perhaps
on the divine agent himself (5.4.1), but on what we may plausibly attribute
to him. So far as I am aware, no theist has specifi ed the divine purpose that
was allegedly served by the creation of the panda’s “thumb.” But let’s posit
one. Let’s assume, for instance, that God’s plan of creation required an
animal that could strip bamboo. Gould’s point is that the panda’s “thumb”
is not the kind of mechanism we would expect God to create, in order to
achieve his purpose. Gould’s argument may be incomplete, as I shall argue
in a moment, or it may be faulty in some other way. But he is surely asking
the right kind of question. His argument rests on the assumption that the
posited divine agent will act rationally. And this rationality principle places
constraints on how God might be expected to act.
5.3 THE OPTIMALITY CONDITION
But of course God is no ordinary agent. So we can also ask what the rationality
principle entails, when applied to God. A key consideration here is
precisely the one to which Sober draws attention—the fact that the agent
posited by a theistic explanation is unique. He has characteristics possessed