SOME PHILOSOPHERS RESORT TO RELATIVE IDENTITY IN ORDER TO DEFEND THE CHRISTIAN DOCTRINE OF THE TRINITY AGAINST ACCUSATIONS OF INCOHERENCE: THEY CLAIM THAT FATHER, SON, AND HOLY SPIRIT ARE NUMERICALLY THE SAME DEITY BUT ALSO NUMERICALLY DISTINCT PERSONS. I ARGUE THAT THEIR CLAIM IS EITHER INCOHERENT OR IMPOSSIBLE TO MOTIVATE. I ALSO ARGUE THAT THE SOCIAL INTERPRETATION OF THE TRINITY, ACCORDING TO WHICH FATHER, SON, AND HOLY SPIRIT ARE DISTINCT "SIMPLICITER", IS NOT OBVIOUSLY UNORTHODOX.

I defend a slightly modified version of geach's rule r, I.E., That although both a and b are g, It is possible for a to be the same f as b and a different h than b, Provided that the question whether a and b are the same g is undecidable. Answering those who object to relative identity I claim that they tacitly adhere to a false fregean view, I.E., That one cannot use a singular term to denote an entity (...) x if it is not true that for every y, X=y or not x=y. I show, However, That such terms are, And must be, Used by every empirically oriented language with finite or infinite predicative arsenal, And hence relative identity is more handy than absolute identity. Finally I give a version of leibniz's law for relative identity. (shrink)

This paper is a reflection on two ontological analogies that have played a role in discussion about the Trinity---the Modalist and Social analogies. I argue that the Modal analogy commits one to a view of the divine persons that comports poorly with Scripture. I then consider two arguments to the effect that the doctrine of the Trinity commits one to tritheism. I argue that the Social analogy contains better resources for handling these arguments than the more traditional position, which involves (...) denying that the divine persons are substances. (shrink)

It would seem that Geach's claim is that the relation expressed by 'is identical with' is like the relation expressed by 'is better than', at least in one respect. If x and y are people, it may turn out that x is a better golfer than y, while y is a better poet than x. If we merely say that x is better than y, we fail to specify the respect in which we hold x to be the better. Another (...) way to put this is to say that we have not made clear "in relation to what" x is the better. We can call the relation expressed by 'is better than' a "relative relation," since an ordered pair of things may stand in that relation relative to one thing but not relative to another thing. Geach seems to think that identity is a relative relation. (shrink)

Absolute identity seems at first sight to be presupposed in the branch of formal logic called identity theory. Classical identity theory may be obtained by adjoining a single schema to ordinary quantification theory.