Princeton, Properties, Plantinga

Alaska was great. Pictures here. I was home for one day and then took off for the Princeton Seminar on Thomism and Analytic Philosophy. It was very thought provoking and full of good students. Of especial interest to me is the idea of more fine-grained modal analysis of certain kinds of properties. For example, consider the property of risibility--the power of seeing humor. This, as the story goes (and it seems like a likely story to me (but not in the Platonic sense of "likely story)) is a part of human nature. Thus, every human has risibility in every world in which they exist. Thus risibility is an essential property of humanity.

However, risibility is derivative (in some yet specified sense) from rationality. We have the ability to perceive humorous incongruities (incongruities are at the heart of most humor) *because* we have rationality. Because of its more basic nature rationality is said to be an essential attribute whereas because of its derivative nature risibility is not, it's an "accidental" property. (I think the odd-to-us use of the term "accident" comes from use by physicians to mean something like "symptom" but I'm not certain about this.)

Thus the Plantingian way of representing essential properties--as those properties had by an entity in every world in which it exists--thus glosses over the Thomistic distinction between "really" essential attributes and accidental properties.

Once upon a time I was quite annoyed by this, but for the life of me I can't remember what was supposed to be so bad about it. It seems we can still formally represent "true" essences--let's just say essences "in the strong sense" (vs. essences in the "weak" sense) as properties which an entity has in every world in which they exist *and which are not explained by any of the other properties which have such status*.

I really do plan to try and find out if there are supposed to be clear problems with this and other problems with Plantingian modality--I'm talking here about problems with the way quantified modal logic represents things, not the obvious problem-to-thomists of the Platonistic metaphysics for modality he offers (though there's nothing in principle--as far as I can see--preventing Plantinga from deflating his properties into concrete entities like God's ideas)--as I say I plan to look into just what the problems are supposed to be here, but that'll have to wait a bit (unless someone wants to tell me).

It certainly is true that Thomas treats of many kinds of modality much subtler than broadly logical necessity, but it seems this can all be handled through restrictions on the accessibility relation in the semantics. We'll have to see.