This entry is a further installment in a continuing discussion with Tim Pawl, et al., about the Chalcedonian Christological two-natures-one-person doctrine. Professor Pawl put to me the following question:
You ask: “Now if an accident is not the sort of item that can be crucified and bleed, how is it that an individual substance can be the sort of item that is not its own supposit or support, that is not broadly-logically-possibly independent, but is rather dependent for its existence on another substance?”
You then say: “That is tantamount to saying that here we have a substance that is not a substance.”
I don’t see that it is tantamount to . . . . And I don’t see the force of the analogy from accidents to individual substances. Could you spell out the reasoning a bit more, if you are inclined?
We all agree that the accidentality of the Incarnation cannot be understood as the having by the Logos of an Aristotelian accident. Thus we all agree that
1. The Logos, while existing in every metaphysically possible world, does not have a human nature in every world in which it exists. That is, the Logos is neither essentially nor necessarily human. (X is essentially F =df x is F in every possible world in which x exists; x is necessarily F =df x is F in every world in which it exists and x exists in every world. For example, Socrates is essentially human but not necessarily human; the number 7 is both essentially prime and necessarily prime.)
2. The Logos' accidentally had humanity (individual human nature) is not an Aristotelian accident of the Logos as Aristotelian substance.
And we all agree why (2) is true. Briefly, an accident is not the sort of item that can be crucified and bleed.
So if the human nature of the Logos is not an accident of any substance, then it is a substance. We now face an antilogism:
3. The individual human nature of the Logos is a substance.
4. Every substance is metaphysically capable of independent existence.
5. The individual human nature of the Logos is not metaphysically capable of independent existence.
The triad is clearly inconsistent: the conjunction of any two limbs entails the negation of the remaining one.
Limb (4) is a commitment of the Aristotelian framework within which Chalcedonian Christology is articulated, while the other two limbs are commitments of orthodox theology.
So something has to give. One solution is to reject (4) by adding yet another 'epicycle.' One substitutes for (4)
4*. Every self-suppositing substance is metaphysically capable of independent existence.
Under this substitution the triad is consistent. For what (4*) allows are cases in which there are substances with alien supposits. The individual human nature of Christ, though a substance, is not a self-suppositing substance: it is not its own supposit. Its supposit is the Logos. So its being a substance is consistent with its not being capable of independent existence.
If I say to Tim Pawl, "What you are countenancing is a substance that is not a substance," I expect him to reply, "No, I am not countenancing anything self-contradictory; I am countenancing a substance that is not a self-suppositing substance!"
To which my response will be: "You have made an ad hoc modification to the notion of substance for the sole purpose of avoiding a contradiction; but in doing so you have not extended or enriched the notion of substance but have destroyed it. For a substance by definition is an entity that is metaphysically capable of independent existence. A substance whose supposit is a different substance is not an accident but it is not a substance either. For it is not metaphysically capable of independent existence."
Recall what my question has been over this series of posts: Is the one-person-two-natures formulation coherently conceivable within an Aristotelian framework?
My interim answer is in the negative. For within the aforementioned ontological framework, the very concept of a primary substance is the concept of an entity that is broadly-logically capable of independent existence. Any modification of that fundamental concept moves one outside of the Aristotelian framework.
Appendix: The Concept of an Accident
What is an accident and how is it related to a substance of which it is the accident? Let A be an accident of substance S. And let's leave out of consideration what the scholastics call propria, 'accidents' that a substance cannot gain or lose. An example of a proprium would be a cat's being warm in virtue of its internal metabolic processes, as opposed to a cat's being warm because it has been sleeping by a fire.
The following propositions circumscribe the concept of Aristotelian accident.
P1. Necessarily, every accident is the accident of some substance or other. (This assumes that there are no accidents of accidents. If there are, then, necessarily, every accident that is not the accident of an accident is the accident of some substance or other.)
P2. No accident of a substance can exist except by existing in (inhering in) a substance. Substances are broadly-logically capable of independent existence; accidents are not. Substances can exist on their own; accidents cannot.
P3. Accidents are particulars, not universals. They are as particular as the substances of which they are accidents. Thus accidents are not 'repeatable.' If Socrates is seated and Plato is seated, and seatedness is an accident, then there are two seatednesses, not one.
P4. Accidents are non-transferrable. Some particulars are transferrable: I can transfer my pen to you. But accidents are not transferrable. I can give you my coat but not my cold. So not only is every accident the accident of some substance or other; every accident is the accident of the very substance of which it is an accident.