The Problems Of Logic For The Trinity

The Problems Of Logic For The Trinity

- According to Michael Rea’s analysis of Relative Identity or Pure Relative Identity is as stated “This chapter begins by describing the doctrine of relative identity (RI) in some detail. It then identifies and describes two versions of the relative identity strategy — the pure RI strategy and the impure RI strategy. It briefly discusses the standard criticisms of the RI strategy. It also presents the objections to that strategy. The chapter argues that invoking the pure doctrine of relative identity as a solution to the problem of the Trinity implies that the difference between the divine persons is theory-dependent, thus forcing either modalism or anti-realism — two equally unpalatable alternatives. It concludes that the RI solution to the problem of the Trinity, taken as a stand-alone solution to that problem, is unsuccessful. ” https://academic.oup.com/book/40088/chapter-abstract/341077586?redirectedFrom=fulltext&login=false

- Classical Trinitarian theology affirms three claims:

(1) The Father is not the Son.
(2) The Father is God.
(3) The Son is God.

But classical logic includes the transitivity of identity:
If A = C and B = C, then A = B.

So if the Father = God and the Son = God, classical logic forces
the Father = the Son, contradicting (1). This is why Relative
Identity is introduced: to deny that identity is absolute and
to allow “same God” without “same Person.”

When we see scholars stating that RI Seems Ad Hoc — Only Used to Save the Trinity Many philosophers argue that RI is not motivated by independent metaphysical reasons. It is introduced only to solve the Trinity puzzle. This makes it look like: a patch, not a theory a special pleading move a logic‑bending workaround rather than a principled metaphysics This is why even sympathetic philosophers (like van Inwagen) treat RI as a last resort. As we saw with Michael C. Rea who is a Trinitarian theologian and Philosopher arguing against R.I, We can also see this in Brian Leftow’s assessment, where he argues that “RI is metaphysically extravagant, unmotivated, and introduced solely to solve the Trinity problem.” H.E.Barber is talked of in this quote from a site “Although Baber argues that this is a “minimally decent” Trinity theory, she admits that it is heretical, and names it a “Neo-Sabellian” theory, because on it, the Persons of the Trinity are non-overlapping, temporary modes of the one God (15; on Sabellianism see section 1.3). But the Persons in this theory are not mere modes; they are truly substances and selves, and there are (at least) three of them, though each is counted as the continuation of the one(s) preceding him. It is unclear whether the theory posits only three selves (10–11). But she argues that the theory is preferable to many of its rivals “since it does not commit us to relative identity or require any ad hoc philosophical commitments”” (link: https://plato.stanford.edu/entries/trinity/)So, under classical Leibniz’s Law of Identity, if three persons are numerically the same one God, they cannot differ in any respect. Therefore, if this principle is true, Yeshua cannot be that same one God, since the one God (and the Father in particular) does not have a hypostatic union, whereas Yeshua does. The difference blocks identity.

So how Relative Identity would make Trinitarianism partialism heresy.

If the Father and the Son differ in properties — for example:

• the Son has a human nature

• the Father does not

• the Son suffers

• the Father does not

• the Son is sent

• the Father sends

— then RI must say:

They differ as persons but are the same God.

But this means:

• “God” is not a full, concrete individual.

• “God” becomes a shared role, kind, or status that both persons participate in.

• The Father and Son are parts or aspects of the one God.

That is partialism:

God = the whole Father + Son + Holy Spirit = parts of that whole

This is exactly the structure RI forces, because the “same God” cannot be a concrete individual if two differing subjects both qualify as it.

Finally relating to Relative Identity and forcing Trinity to be multiple gods.If the Father and Son each have non‑shared essential properties, then even RI cannot maintain that they are “the same God” without contradiction.

For example:

• The Son has a human nature (essential to his identity as Jesus).

• The Father does not and cannot have one.

These are essential differences, not accidental ones.

Under any identity theory — even RI — if two beings have different essential properties, they cannot be the same concrete entity.

So RI ends up implying:

• The Father is a divine being with property‑set F.

• The Son is a divine being with property‑set S.

• F ≠ S.

• Therefore, they are two distinct divine beings.

That is simply two gods.

RI tries to avoid this by saying “same God, different person,” but the property‑sets force the metaphysics toward numerical distinctness.

Why Relative Identity can not hold the middle ground logically.RI was invented to avoid the classical identity problem:

• If Father = God

• and Son = God

• then Father = Son

But once you allow:

• differing properties

• differing consciousnesses

• differing wills

• differing natures

…you cannot maintain a single concrete divine being.

So RI ends up in one of two places:

A. Partialism

God = a whole composed of three personal parts.

B. Polytheism

Father and Son = two distinct divine beings with different essential properties.

There is no stable middle position.

Relating the one person of Yeshua but two sortals in the relative identity modle Sortals are identity‑fixing — you can’t have two without contradiction

A sortal is a category that:

• tells you what something is

• determines how many there are

• fixes identity conditions

Examples: person, cat, triangle, God, human.

If one individual falls under two identity‑fixing sortals, you get:

• two incompatible sets of identity conditions

• two incompatible criteria for persistence

• two incompatible essential properties

This is metaphysically unstable.

So:

• “God” is a sortal with divine identity conditions.

• “Human” is a sortal with human identity conditions.

One person cannot satisfy both without contradiction

A divine nature includes:

• omniscience

• omnipotence

• omnipresence

• impassibility

• eternality

• necessary existence

A human nature includes:

• limited knowledge

• limited power

• spatial location

• passibility

• temporal existence

• contingent existence

These are contradictory essential properties.

One person cannot simultaneously have:

• necessary existence and contingent existence

• omniscience and limited knowledge

• impassibility and suffering

• omnipresence and spatial location

This is a direct violation of Leibniz’s Law.

If one person has:

• a divine mind (infinite)

• a human mind (finite)

…then you no longer have one person.

You have:

• two centers of consciousness

• two sets of beliefs

• two wills

• two intellects

That is two persons, not one.

This is why many philosophers say classical Christology collapses into Nestorianism (two persons).

Summary: If one person falls under two sortals — divine and human — you get contradictory essential properties, two minds, two wills, and incompatible identity conditions. This forces either Nestorianism (two persons), Docetism (no real humanity), or Modalism (no real distinction). The “one person, two natures” model is metaphysically unstable under classical identity.