Joseph Jedwab

The Doctrine of the Trinity says that there is one God, that there are three divine Persons, and that each divine Person is God. The Logical Problem of the Trinity is that these claims seem logically inconsistent. We argue that any coherent and orthodox solution to the Logical Problem must use the technique of paraphrase: a logically or metaphysically more perspicuous reformulation. If so, discussions of paraphrase deserve more prominence in the literature on the Doctrine of the Trinity. We also show that such explicit discussion has important implications for theorizing about the Trinity.

Relative-identity theories of the Trinity and Incarnation are worth another look. But not all such theories are the same. One important difference among them concerns restricted quantification. Peter Geach proposes two theses: the sortal relativity of identity and the irreducibility of restricted quantification. Every relative-identity theory of the Trinity and Incarnation applies Geach’s first thesis. But only what I call “the Geachian theory” applies both theses. I argue that any such Geachian theory faces significant theoretical disadvantages. Towards the end, I propose a closely related but non-Geachian relative-identity theory that doesn’t share those theoretical disadvantages.