Reduplication and the Two Natures of Christ
According to Chalcedonian orthodoxy, God the Son, the second person of the Trinity, became man in Jesus of Nazareth. It was not God simpliciter who became man, but God the Son. In becoming man, the Son did not cease being divine. Thus the Chalcedonian formula implies that one and the same person, Christ, from the historical moment of Incarnation on, is in full possession of two distinct natures, one divine, the other human.
How is this possible? How can one individual, one person, exemplify two natures? The problem arises because the two natures are such that each includes properties logically incompatible with properties included in the other nature. For example, anything human is mortal, while anything divine is immortal. Anything human is limited in power, while anything divine is unlimited in power. Anything human is liable to suffer, while anything divine is impassible. And so on. So if Christ is human (possesses human nature), then he is mortal and limited in power, while if he is divine, then he is immortal and unlimited in power. It seems to follow that one and the same person, Christ, is both mortal and immortal, and limited and unlimited in power.
Now among the pious and scoffers alike, there are those who gleefully gloat over contradictions, but I pronounce my anathema upon them. Unless we want to lose our minds, we should have no truck with irrationalists like Tertullian and Kierkegaard. If we are clear about this, we can proceed to the question whether the apparent contradiction can be shown to be merely apparent.
One strategy makes use of reduplicative propositions. Using such propositions, one can say of an individual x that it is H in respect of being F, but not H in respect of being G. By distinguishing the respects in which x is H and not H, one hopes to avoid contradiction. Thus one might say that Christ as man is mortal, but Christ as God is immortal, and similarly for other cases.
Now we do sometimes talk this way. We might say that Sally has the right to vote in virtue of her being an adult citizen (who has never committed a felony, etc.) but does not have the right to vote in virtue of her being female. We defuse the apparent contradiction of saying that Sally has the right to vote and does not have the right to vote by saying that she has the right to vote qua adult citizen but not qua female. Note that Sally’s being an adult citizen includes her right to vote, but that her being female neither includes nor excludes her right to vote.
Similarly with Dienekes’ example of Bob who is both husband and captain. Bob’s being a husband includes his divorceability, but his being a captain neither includes nor excludes his divorceability. Dienekes thinks that the unproblematic nature of this example shows that it is unproblematic to hold that Christ is both man and God. I believe he is wrong about this.
The reduplicative propositions about Sally and Bob do not boil down to contradictions. But ‘Christ as man is mortal and Christ as God is immortal’ does boil down to a contradiction. For Christ’s being a man includes his being mortal, and Christ’s being God includes his being immortal. Since Christ is both man and God, he is both mortal and immortal – which is a contradiction.
In sum, the reduplicative strategy is of no use in showing the logical tenability of the two natures doctrine. The schema is this:
S. x as F is H & x as G is not H.
(S) reduces to the contradiction x is H & x is not H if the following condition is met:
C. F-ness entails H-ness & G-ness entails non-H-ness.
The Sally and Bob examples fit the reduplicative schema (S) but do not satisfy the entailment condition (C). Thus they are DISANALOGOUS to the Christological cases which do satisfy (C).
To read a technical paper of mine on the Incarnation, go here.