According to Aquinas, whenever we correctly say something non-negative of God, we speak analogically.
It is correct to say that Socrates is wise and God is wise. But being humanly wise and divinely wise are different—the most fundamental difference being that, by divine simplicity, God doesn’t have his wisdom, but is his wisdom. But this leads to:
- The predicate “is humanly wise or is divinely wise” applies literally to both Socrates and God.
And yet this disjunctive predicate is not negative, so (1) seems to provide a counterexample to Aquinas’ theory.
But this is too fast. Claim (1) only provides a counterexample to Aquinas’ theory if:
- Applying analogically and applying literally are incompatible.
But I think Aquinas can, and should, say that (2) is false. If he does that, then he can affirm both (1) and:
- The predicate “is humanly wise or is divinely wise” applies analogically to both Socrates and God.
In fact, I think Aquinas can say that the relevant kind of analogical application of predicates is a special case of literal predication.
I think that Aquinas is not really making a claim about literal and non-literal use of words when he is talking of analogical predication. Instead, I think he is making a claim about grounding, somewhat like:
- The predicate “is F” is used analogically between entities x and y just in case the propositions that x is F and that y is F have a relevantly different grounding structure.
On this account, disjunctive predicates like “is a human or a dog” are used analogically: for the grounding structure of the proposition that Alice is a human or a dog is that it’s grounded in Alice being a human, while the grounding structure of the proposition that Fido is a human or a dog is that it’s grounded in Fido being a dog. And similarly, “is humanly wise or is divinely wise” is used analogically, since in the case of Socrates the grounds of applicability are Socrates having wisdom and in the case of God the grounds are God being (his) wisdom.
Notice that on this story, Aquinas’ claim about analogical predication is not so much a linguistic claim as a metaphysical claim about the truth grounds.
The story makes clear why negative predicates are not used analogically: for the grounding structure of the truth that God is not a bicycle and the truth that Alice is not a bicycle is relevantly the same—both are grounded in not being arranged bicycle-wise.
So far, our reconstruction of Aquinas’ theory of predication is:
- A predicate that applies to God is negative or is used analogically.
But that’s not quite right. Here is one counterexample: “is not a bicycle or is both a bicycle and a non-bicycle.” This predicate is not negative but disjunctive. But it applies to God and to Socrates in the same way—by both not being bicycles.
I think the issue here is this. Just as analogical predication is a metaphysical and not linguistic notion, so negative predication is a metaphysical and not linguistic notion. We might say something like this:
- The predicate “is F” is used negatively of entity x just in case what grounds x being F is the non-obtaining of some state of affairs.
Thus, “is not a bicycle or is both a bicycle and non-bicycle” is used negatively of both God and Socrates, because what grounds its application in both cases are respectively the non-obtaining of the states of affairs of God being arranged bicycle-wise and of Socrates beng arranged bicycle-wise. On the other hand, the disjunctive predicate “is Athenian or not Greek” is used negatively of God and non-negatively of Socrates. Interestingly, this case shows that the disjunction in (5) is not exclusive. For “is Athenian or not Greek” is used both negatively of God and is used analogically between Socrates and God, since the structure of the grounds of application is relevantly different.
The problems haven’t all gone away. A necessary condition for “is F” to be used analogically of God and a creature is that “is F” applies to God and a creature, and hence a predicate that applies only to God cannot be used analogically. But suppose that in fact no one other than God knows whether the Continuum Hypothesis is true. Then the predicate “knows whether the Continuum Hypothesis is true” is not used analogically, since it only applies to God. But then we have a counterexample to (5).
We could try to modalize (4): a predicate is used analogically provided that it could have one ground as applied to God and another as applied to something other than God. But, again, it’s not hard to come up with a counterexample: “knows that 2 + 2 and is not a creature.” For that predicate can only apply to God.
We could also weaken (5) to merely apply to those predicates that apply (or could apply) to both God and a creature. This may seem to be an undue weakening: now one can escape from Aquinas’ doctrine of analogical predication simply by saying things that only apply (or could only apply) to God. But perhaps one can supplement the weakened (5) with:
- Any predicate that applies to God is built out of predicates that apply both to God and to a creature.
I am not too happy about this.