Peter Lupu writes,
The following are some recent thoughts about the Trinity. Let me know what you think.
The three expressions of the Trinity: ‘The Father’, ‘The Son’, and ‘The Holy Spirit’ all refer to the same divine being namely God. Thus, with respect to reference, each pair of expressions forms a true identity. However, they have different senses in Frege’s sense. The three senses are as follows:
1) The sense of ‘The Father’ is the will of the divine being to love, atone, and forgive. Call this the divine-will.
2) The sense of ‘The Holy Spirit’ is the will of a non-divine being when and only when it genuinely aspires to be like the divine with respect to its moral identity and worth. Call this the inspired-will.
3) The sense of ‘The Son’ (i.e., the person of Jesus) is when the divine-will and the inspired-will coincide in a human person such as Jesus. Thus, Jesus is a moral-exemplar (Steven’s term) of a case when the divine-will and the inspired-will seamlessly coincide.
The senses of the three expressions of the Trinity are different. Therefore, while identities among each pair with respect to their senses are false, identities with respect to their referents are true.
It warms my heart that a Jew should speculate on the Trinity on Good Friday. Rather than comment specifically on the senses that Peter attaches to 'the Father,' 'the Son,' and 'the Holy Spirit,' I will address the deeper question of whether the logical problem of the orthodox doctrine of the Trinity can be solved by means of Gottlob Frege's distinction between the sense and the reference of expressions.
The Logical Problem of the Trinity
Our question concerns the logical consistency of the following septad, each limb of which is a commitment of orthodoxy. See here for details. How can the following propositions all be true?
1. There is only one God.
2. The Father is God.
3. The Son is God.
4. The Holy Spirit is God.
5. The Father is not the Son.
6. The Son is not the Holy Spirit.
7. The Father is not the Holy Spirit.
If we assume that in (2)-(7), the 'is' expresses absolute numerical identity, then it is clear that the septad is inconsistent. (Identity has the following properties: it is reflexive, symmetric, transitive, governed by the Indiscernibility of Identicals and by the Necessity of Identity). For example, from (2) and (3) taken together it follows that the Father is the Son by Transitivity of Identity. But this contradicts (5).
So we have an inconsistent septad each limb of which is a commitment of orthodoxy. The task is to remove the contradiction without abandoning orthodoxy. There are different ways to proceed. Here I consider only one, the Fregean way. (Of course, Frege himself did not address the Trinity; but we may address it using his nomenclature and conceptuality.)
The Fregean solution is to say that 'Father,' 'Son,' and 'Holy Spirit, are expressions that differ in sense (Sinn) but coincide in reference (Bedeutung). Frege famously gave the example of 'The morning star is the evening star.' This is an identity statement that is both true and informative. But how, Frege asked, could it be both? If it says of one thing that it is identical to itself, then it is true but not informative because tautological. If it says of two things that they are one thing, then it is false, and uninformative for this reason. How can it be both true and nontautological?
Frege solved his puzzle by distinguishing between sense and reference and by maintaining that reference is not direct but routed through sense. 'Morning star' and 'evening star' differ in sense, but coincide in reference. The terms flanking the identity sign refer to the same entity, the planet Venus, but the reference is mediated by two numerically distinct senses. The distinction allows us to account for both the truth and the informativeness of the identity statement. The statement is true because the two terms have the same referent; the statement is informative because the two terms have different senses. They are different modes of presentation of the same object.
Now let's apply this basic idea to the Trinity. To keep the discussion simple we can restrict ourselves to the Father and the Son. If we can figure out the Binity, then we can figure out the Trinity. And if we restrict ourselves to the Binity, then we get a nice neat parallel to the Fregean example. The Frege puzzle can be put like this:
a. The Morning Star is Venus
b. The Evening Star is Venus
c. The Morning Star is not the Evening Star.
2. The Father is God
3. The Son is God
5. The Father is not the Son.
Both triads are inconsistent. The solution to the Fregean triad is to replace (c) with
c'. The sense Morning Star is not the sense Evening Star.
The suggestion, then, is to solve the Binity triad by replacing (5) with
5'. The sense Father is not the sense Son.
The idea, then, is that the persons of the Trinity are Fregean senses. To say that the three persons are one God is to say that the three senses, Father, Son, Holy Spirit, are three distinct modes of presentation (Darstellungsweisen) of the same entity, God.
Why the Fregean Solution Doesn't Work
Bear in mind that we are laboring under the constraint of preserving orthodoxy. So, while the Fregan approach is not incoherent, it fails to preserve the orthodox doctrine. One reason is this. Senses are abstract (causally inert) objects while the persons of the Trinity are concrete (causally efficacious). Thus the Holy Spirit inspires people, causing them to to be in this or that state of mind. The Father begets the Son. Begetting is a kind of causing, though unlike empirical causing. The Son loves the Father, etc. Therefore, the persons cannot be Fregean senses.
Furthermore, senses reside in Frege's World 3 which houses all the Platonica necessary for the semantic mediation of mental contents (ideas, Vorstellungen, etc.) in World 2 and primary referents in World 1. Now God is in World 1. But if the persons are senses, then they are in World 3. But this entails the shattering of the divine unity. God is one, three-in-one, yet still one. But on the Fregean approach what we have is a disjointed quaternity: God in World 1, and the three persons in World 3. That won't do, if the task is to preserve orthodoxy.
At this point, someone might suggest the following. "Suppose we think of senses, not as semantic intermediaries, but as constituents of the entity in World 1. Thus the morning star and the evening star are ontological parts of Venus somewhat along the lines of Hector Castaneda's Guise Theory. To say that a sense S is of its referent R is to say that S is an ontologcal part or constitutent of R. And then we can interpret 'The Morning Star is the Evening Star' to mean that the MS-sense is 'consubstantiated' (to borrow a term from Castaneda) with the ES-sense. Thus we would not have the chorismos, separation, of senses in Worldf3 from the primary referents in World 1: the senses would be where the primary referents are, as ontological parts of them.
But this suggestion also violates orthodoxy. The persons of the Trinity are not parts of God; each is (identically) God. No proper part of a whole is identical to the whole. But each person is identical to God.
I conclude that there is no Fregean way out of the logical difficulties of the orthodox Trinity doctrine. If so, then Peter's specific suggestion above lapses.