The Logic of the Incarnation: Response to Fr. Kirby

I presented the following argument in a response to Dr. Vito Caiati:

a. The Second Person of the Trinity and the man Jesus differ property-wise.  
b.  Necessarily, for any x, y, if x, y differ property-wise, i.e., differ in respect of even one property, then x, y are numerically different, i.e., not numerically identical.  (Indiscernibility of Identicals)
Therefore
c. The Second Person of the Trinity and Jesus are not numerically identical, i.e., are not one and the same.

I went on to say that the argument is valid and the premises are true.

(a) is true as a matter of orthodox -- miniscule 'o' -- Christian teaching.  (b) is the Indiscernibility of Identicals, a principle whose intellectual luminosity is as great as any.  But the conclusion contradicts orthodox Christian teaching according to which God, or rather the Second Person of the Trinity, became man, i.e., became identical to a flesh and blood man with a body and a soul, in Jesus of Nazareth at a particular time in an obscure outpost of the Roman empire.

Yesterday morning's mail brought a formidable response from Down Under by Fr. Matthew Kirby:

You posit as a purportedly orthodox premise in a recent post: "The Second Person of the Trinity and the man Jesus differ property-wise."

However, this is not orthodox, but implicitly Nestorian if taken strictly literally. To put it simply, it assays to distinguish between two personal subjects, the SPT and Jesus, in terms of their properties, but the unity and identity of subject is in fact the dogmatic requirement. It is equivalent to unity of the Person. Putting the word "man" in front of Jesus does not change this, because the man Jesus is in fact the person Jesus who has two natures, divine and human. Jesus is not the name of a nature, of that Person's manhood, it is a proper name belonging to the Person as a whole, on orthodox premises. If you want to change the second "subject" to "Jesus' humanity only", then you will be comparing a Person to an ontological component of that same person, and would only "differ" in the way a subset differs from that set of which it is a subset. (This talk of components does not contradict Divine Simplicity because that simplicity refers to the Divine Nature only.) The SPT has the property of, for example, physical extension, via his human nature,  but not via his divine nature. But he really possesses that property, in precisely that sense.

Fr. Kirby clearly knows his theology.  I write these weblog entries quickly and I unaccountably blundered by saying that (a) is orthodox Christian teaching. The premise is nonetheless defensible, though surely not anything an orthodox Christian would say in explanation of his doctrine.   I won't insist on the truth of premise (a), however, but approach the question from a different angle.  Putting myself on Kirby's ground, I grant that "the unity and identity of subject is in fact the dogmatic requirement." 

On classical Christology, as defined at the Council of Chalcedon in anno domini 451, Christ is one person with two distinct natures, a divine nature and a human nature.   Thus Christ is fully divine and fully human. But isn't this just logically impossible inasmuch as it entails a contradiction?  If Christ is divine, then he is immaterial; but if he is human, then he is material.  So one and the same person is both material and not material.

Again, if Christ is divine, then he is a necessary being; but if he is human, then he is a contingent being.  So one and the same person is both necessary and not necessary.  Furthermore, if Christ is divine, and everything divine is impassible, then Christ is impassible; but surely no human being is impassible. So if Christ is human, then Christ is not impassible. The upshot, once again, is a contradiction: Christ is impassible and Christ is not impassible.

One way to try to evade these sorts of objection is by way of reduplicative constructions.  Instead of saying that Christ is both all-powerful and not all-powerful, which is a bare-faced contradiction, one could say that Christ qua God is all-powerful, but Christ qua man is not all-powerful. But does this really help? There is still only one subject, one person, one hypostasis, one suppositum,  that has contradictory attributes.  

For it is not the divine nature that has the property of being all-powerful, and it is not the human nature that has the property of being limited in power, but the bearer of these natures.  The bearer of a nature is obviously distinct from nature whose bearer it is. So the bearer of these two natures is both unlimited in power and limited in power, which is a contradiction.

Here is an analogy to help you see my point. Suppose we have a sphere the northern hemisphere of which is green, and the southern hemisphere of which is red, hence non-green.  Is such a sphere logically possible? Of course. There is no violation of the Law of Non-Contradiction, the central principle of the discursive intellect (whether or not it is the central principle of all reality.)   This is because the predicates 'green' and 'red' do not attach to one and the same item, the sphere, but to two different mutually exclusive proper parts of the sphere, the northern and southern hemispheres respectively.

But Christ, or rather Christ as depicted in Chalcedonian orthodoxy, is not like the sphere that is both green and red.  The northern and southern hemispheres instantiate being green and being red, respectively. But the divine and human natures of Christ  do not instantiate the properties of being unlimited in power and limited in power, respectively.  It is Christ himself who instantiates the properties. But then the contradiction is upon us.

So as I see it the reduplicative strategy doesn't work. It is that strategy that Fr. Kirby relies on when he writes, "The SPT has the property of, for example, physical extension, via his human nature,  but not via his divine nature." This is equivalent to saying that the Second Person is physically extended qua human, but not physically extended qua divine.  But that boils down to saying that the Second Person is physically extended and not physically extended.  

This is because a mark of a nature is not a property of that nature but a property of the subject that bears the nature.  Human nature, for example, includes the mark being an animal.  This mark is included within human nature but is not a property of human nature, and this for the simple reason that no nature is an animal. Socrates is an animal, but his nature is not.  

Now Christ is said to have two natures.  Human nature includes among its marks being susceptible to suffering, and divine nature  includes among its marks being insusceptible to suffering. Since the bearer (subject) of a nature has the marks included in its nature(s), it follows that Christ is both susceptible to suffering and insusceptible to suffering.  And that is a contradiction.

Fr. Kirby also writes,

It is thus orthodox to call Mary the Mother of God (even though she was only the source of Jesus' humanity and only physically enclosed in her womb the human nature) and say God died on the Cross (even though the Divine Nature is absolutely impassible and immortal and only God the Son's humanity could be killed.) Why? Because motherhood is an inter-personal relation, and because all of Christ's human actions are personal acts of a Divine (as well as human) Subject. 

Mariology is fascinating but I won't comment on that now. But if Christ is (identically) God the Son, and Christ died on the Cross, then God the Son died on the Cross. But no divine being can literally die, and God the Son is a divine being.  It follows that Christ is not God the Son.

Fr. Kirby will resist the conclusion by saying  that it was not God the Son who died on the Cross, but God the Son's humanity or human nature.  But by my lights this make no sense.  A flesh and blood human being died, not the nature of a human being.  It makes no sense to say that a nature lives or dies, breathes or sheds blood.

"But what if the nature is identical to its bearer?"  That is ruled out in this case because Christ has two distinct natures.  Now if N1 is not identical to N2, then neither can be identical to their common bearer B.  For if N1 = B, and N2 = B, then N1 = N2, contrary to hypothesis.

From here the dialectic plunges deeper and deeper into the connundra and obscurities of Aristotelian metaphysics, but it is time to punch the clock.

Concluding Aporetic Postscript

I should note that I have not refuted the Incarnation; at best I have given good reasons for doubting the logical coherence of a certain dogmatic conceptualization of the Incarnation.  Maybe there is an alternative conceptualization that fares better; or maybe we should go mysterian.

Comments

[Fr Matthew Kirby]

Dr Vallicella,

You say: "Here is an analogy to help you see my point. Suppose we have a sphere the northern hemisphere of which is green, and the southern hemisphere of which is red, hence non-green. Is such a sphere logically possible? Of course. There is no violation of the Law of Non-Contradiction, the central principle of the discursive intellect (whether or not it is the central principle of all reality.) This is because the predicates 'green' and 'red' do not attach to one and the same item, the sphere, but to two different mutually exclusive proper parts of the sphere, the northern and southern hemispheres respectively."

Well, that is in fact a reasonable analogy for the Incarnation, allowing for the infinite ontological difference between the two "parts" there. After all, the dogma also states that there is no mixture of qualities between the divinity and humanity, such that they remain genuinely distinct without being separated. And in the same way that the predicates red and green do attach to the sphere abovementioned, via its proper parts, so do the distinctly human and divine attributes attach to the SPT, via his distinct parts. I cannot help but wonder whether you are implicitly interpreting the traditional Creedal summary "Fully God, Fully Man" to mean "Wholly divine qualitatively, wholly human qualitatively", which would indeed be a contradiction. Christ has all divine attributes (in his divine nature) and all human attributes (in his human nature), but his attributes are not all divine, or all human.

You deny this part-wise distribution by rendering the relevant natures as abstractions in themselves, it seems, here: "This is because a mark of a nature is not a property of that nature but a property of the subject that bears the nature. Human nature, for example, includes the mark being an animal. This mark is included within human nature but is not a property of human nature, and this for the simple reason that no nature is an animal. Socrates is an animal, but his nature is not." But the two natures of Christ are not being talked about in the traditional teaching as non-substantiated forms, or as mere essences logically prior to the question of existence. The divine nature could not be talked about in this sense because it is the intrinsically self-subsistent Form, so to speak. And the human nature referred to in the teaching is Christ's human nature as "already" substantiated by and subsistent in the SPT, as shown by the way it is talked about in the Tome of Leo. In this context then, rather than saying "a mark of a nature is not a property of that nature but a property of the subject that bears the nature", we should say that a mark of a nature is indeed a property of a nature inasmuch as that nature is substantiated, because that mark is the property of the subject via and only via that nature it instantiates.

Socrates is an animal, precisely because his human nature is, inter alia, an animal nature, such that his human nature as substantiated in him is an animal. This cannot be said about his nature considered purely in abstraction from its actualisation, I grant. But the two natures of Christ are not conceptualised in that way by the Chalcedonian doctrine. Indeed, remember that the "Athanasian Creed" and other dogmatic sources (cf. Cat. of the Cath. Ch. 467) in their English and Latin translations repeatedly equate "nature" in this context with "substance"/"substantia".

You also claim: "Fr. Kirby will resist the conclusion by saying that it was not God the Son who died on the Cross, but God the Son's humanity or human nature. But by my lights this make no sense. A flesh and blood human being died, not the nature of a human being. It makes no sense to say that a nature lives or dies, breathes or sheds blood." No, I won't say that at all, as it would be heretical. God the Son did die on the Cross, as his human substance suffered death even though his divine substance did not.

Similarly, I will say unreservedly that I, Fr Kirby, typed this response and felt the impact of the keyboard in doing so, even though I will deny vehemently that either my appendix or my little toe typed this response or touched the keyboard. (For which my computer, were it sentient, would be grateful, no doubt.) And I will even, just to push the supposedly aporetic boundaries further, still continue to insist that my appendix and little toe subsist in me and are part of my nature/substance. :-)

[Fr Matthew Kirby]

As a postscript, permit me also to say that I think the Christian metaphysics virtually demands two distinct and irreducible but inter-related aspects of ultimate "concretisation" or "individuation" at the root of things. Where living beings, especially persons, are concerned, I think that who-subjectivity (i.e., personal subsistence as the fundamental agent and identity) is one kind and what-"subjectivity" or thing-ness (natural substance as the objective reality) is another. I'm sorry to put it all so terribly awkwardly.

In the Trinity, there are three personal subsistences but one natural substance in common. In the Incarnation, one personal subsistence with two natural substances. In each of us, personal subsistence underlies, I think, our individuated human substance.

Some speculations/questions: Does natural substance concern primarily the (true) view of a being's fundamental reality from the outside and personal subsistence the (true) view of its fundamental identity from the inside of the living agent? Could this mean that full Revelation of the Trinity required that we first be drawn into the midst of the Divine life? That the OT's revelation had to dwell on the truth of the unity almost exclusively because that level of incorporation and inward insight awaited the Incarnation and its redemptive, adoptive acts? Although this view of the "who" and the "what" seems to introduce an inescapable and unacceptable ultimate dualism at first, with "who-ness" nevertheless gaining a kind of priority, does the revelation "God is love" transcend the distinction, so to speak, by making that "What" finally equivalent to the internal "I-Thou"s of the "Who"?

[BV]

Fr. Kirby,

Thank you for the detailed comments. It is interesting that you find that my sphere analogy supports your point of view.

>>And in the same way that the predicates red and green do attach to the sphere abovementioned, via its proper parts, so do the distinctly human and divine attributes attach to the SPT, via his distinct parts.<<

Well, I deny that predicates attach to the sphere. If they did, the sphere would be both green and not green.

>>You deny this part-wise distribution by rendering the relevant natures as abstractions in themselves,<<

Not really. I grant that the natures cannot exist in a Platonic realm apart, but only in the suppositum. My point is that, even so, there is a distinction between the suppositum and the natures.

>> remember that the "Athanasian Creed" and other dogmatic sources (cf. Cat. of the Cath. Ch. 467) in their English and Latin translations repeatedly equate "nature" in this context with "substance"/"substantia".<<

This is the problem in a nutshell. That equation is an affront to the discursive intellect. We will have to leave it here for now.

But let me say one more thing. The Incarnation is an absolutely unique event. Problems arise when we try to understand it in terms of models derived from a metaphysics that applies to objects of ordinary experience.

God too is absolutely unique. This is why, when you think it through, you are driven to the doctrine of divine simplicity -- which makes no sense to the discursive intellect.

Same with the Trinity. Absolutely unique. Can't be modeled.

[Fr Matthew Kirby]

Perhaps the essential problem is that the Tradition and I (and everyday language as well) are doing predication somewhat differently to you. (I am not skilled or knowledgeable enough in Analytic philosophy to know whether your "grammar" is the only one accepted in that system.)

For us, to predicate of Fr Kirby that he typed this response, or of the sphere aforementioned that it possesses the quality of redness, or of the SPT that he preached the Sermon on the Mount, does not require that all parts of Fr Kirby participated in the action of typing, that all of the sphere is red, or that Jesus' Divine nature was directly responsible for the production of sound waves. Similarly, when we say that a medical patient is sick or has cancer, we do not necessarily mean that every part of his body is affected.

For you, it seems predication regarding an integral whole entity is invalid if qualified by non-universality within the entity. "Simpliciter" or absolute, unqualified predication is all that is allowed.

But the creedal statements do not try to follow your rules. For us, to say Jesus is truly human and truly divine, is not to say every component of him is divine, or every component of him is human.

Finally, I would say that the distinction between the nature and the suppositum is not the only important factor for properly interpreting the Creeds. First, I think supposita can have hierarchical levels of instantiation within them in this context: The personal hypostasis being "below" the natural substances here, and the human substance subsisting in the one hypostasis with its divine essence, the latter creating it for itself (hence enhypostasis). Second, the interdependence of suppositum and nature in their "fusion" is what determines the shape of the Creedal propositions. Each nature is considered as it is already actualised by the suppositum, and the suppositum's "predicates" are possessed (and predicated!) strictly via each nature but truly possessed by the one hypostasis nonetheless.

[Fr Matthew Kirby]

A really, truly final comment before I stop bugging you about this Dr Vallicella.

I agree with you that:

"The Incarnation is an absolutely unique event. Problems arise when we try to understand it in terms of models derived from a metaphysics that applies to objects of ordinary experience.

God too is absolutely unique. This is why, when you think it through, you are driven to the doctrine of divine simplicity -- which makes no sense to the discursive intellect.

Same with the Trinity. Absolutely unique. Can't be modeled."

I just think that "makes no sense" corresponds to "anti-intuitive to some extent" or "unimaginable", not to "formally contradictory". Also, I would prefer to say that analogies for the Trinity will always fail in particular, important ways, rather than that such models/analogies are non-existent or useless.

In any case, I'll give it a rest now, and let you have the last word, if you wish it. Thank you for interacting with me. I'm trying to punch above my weight, I suspect, intellectually, but it's been fun.

God bless.

[BV]

Fr. Kirby,

We may actually be closer think you think.

I don't have time to respond in detail to the above, and in any case I have discussed these matters in greater detail and with greater rigor in earlier posts. If you have the time and the desire, take a look at the contents of my Trinity and Incarnation category: http://maverickphilosopher.typepad.com/maverick_philosopher/trinity-and-incarnation/

I have three or so posts in which I interact with Tim Pawl, a Catholic expert on Christology. I beleieve he has a book out on the topic.

Thank you again for your comments, and best wishes.