Aquinas on Christ (ST III, q.17 a.1–q.18 a.1): One Being and Two Wills

Orientation #

He opens by returning to question 17, article 1, “to look a little bit more” at the replies to the last three objections, then goes on to a. 2 and into q. 18. He says the article on the will (q. 18, a. 1) is “easier,” and that the operations come “in the next question nineteen.” The neighbouring classes treat the same stretch of the Tertia Pars on the unity of Christ.

The class, in order #

1. Opening prayers and feast days (“the stigmatization of Saint Francis”) #

Prayer to God, the guardian angels, and Thomas Aquinas. Chat about the 17th of September: Robert Bellarmine, the stigmatization of St Francis, Albert of Jerusalem, and St Sophia with her three martyr daughters (a student’s granddaughter’s feast). An aside on Bellarmine and Cornelius a Lapide, both Jesuits.

2. Q. 17, a. 1, replies 5-7: why Christ is not “two” (“that the two of you doesn’t seem exactly right”) #

The point: predication follows the suppositum, so the duality of natures does not make Christ two simply.

• ad 5: in the Trinity the divine nature can be said in the abstract of the three persons, so one says simply that the three persons are one. In the incarnation both natures are not said in the abstract of Christ, so one cannot say simply that Christ is two — only secundum quid, i.e. two in nature.
• ad 6: “two” is said as having duality, not in something else but in the very one of whom the two are said; predication is made of the suppositum indicated by the name “Christ.” Christ has a duality of natures but not of supposita, so not two without qualification.
• ad 7: alterum implies a diversity of accident, and a diversity of accident suffices for something to be called alterum simply. Aliud implies a diversity of substance — and substance means not only the nature but also the suppositum (Aristotle, fifth book of wisdom [ed.: Metaphysics V]). So diversity of nature does not make something aliud simply without diversity of suppositum; it makes it other only secundum quid, according to nature.
• Example/joke: if Christ appeared to you, you should not say “the two of you” — “Didn’t Thomas teach you how to speak to me?” You may talk about his two natures.

3. Q. 17, a. 2: the four objections to one esse (“there is not only one to be… but what two?”) #

1. Damascene (third book): what follows upon the nature in Christ is doubled; but esse follows the nature, for to be is from the form; so two beings.
2. The esse of the Son of God is the divine nature itself and eternal; the being of the man Christ is not the divine nature but temporal, “in the fullness of time”; so not only one esse.
3. (He calls this “an interesting argument.”) In the Trinity, three persons but one esse on account of unity of nature; in Christ two natures though one person; therefore two esse.
4. In Christ the soul gives some existence to the body, since it is its form; but it does not give divine being, which is uncreated; so there is another esse besides the divine.

• Aside: his former student studied with the Dominicans, and one teased her that he would ask her this on her final exam — “the meanest thing you could possibly do to somebody in an exam.” And: “the duty of the teacher is to confuse the issue.”

4. The sed contra and a digression on convertibility (“because one and being are what convertible”) #

Sed contra: each thing, according as it is said to be a being, is said to be one, since one and being are convertible; so if there were two esse in Christ he would be two and not one.

• What convertible means: a thing and its definition; a thing and its property in the strict sense. Examples: every square is an equilateral right-angled quadrilateral and conversely; every two is half of four and everything half of four is two.
• Aristotle at the beginning of the fourth book of wisdom [ed.: Metaphysics IV]: wisdom is of being as being and of the one and the many; the consideration of being and of one is in a way the same, but they differ in definition — one adds negation, undivided being. He notes Thomas also treats this in the prima pars on the unity of God, and that he was reading an objection in the Sentences commentary today: do being, one, good, true add something to the definition? Thomas answers they add something, but something that falls upon all being — hence convertible.
• Fuller sense of one: undivided in itself, distinct from everything else.
• Socratic use: “What is a dog?” — “a four-footed animal.” Socrates turns it around: is every four-footed animal a dog? If you cannot turn it around, your definition is not complete.

5. Body of a. 2: esse belongs to the hypostasis as that which has it (“but to the nature, as to that by which something has existence”) #

Since in Christ there are two natures and one hypostasis (hence hypostatic union: the natures do not become one nature, but are united in one hypostasis subsisting in both), what pertains to nature in Christ is two, what pertains to the hypostasis is one only.

• Esse pertains to both but not in the same way: to the hypostasis as to that which has existence; to the nature as that by which something has existence — nature is signified by way of form. Examples: by whiteness something is white; by humanity someone is a man; by health you are healthy.
• Distinction: a form that does not pertain to the personal existence of the subsisting hypostasis gives an esse only secundum quid, and such esse can be multiplied — the esse by which Socrates is white differs from that by which he is musical.
• His own case: “When I came to be in this room, I got a new being” — secundum quid. You wouldn’t say simply that he came to be today. Joke: “If you leave this room, you will cease to be” — unqualified, it sounds like a threat.
• But the esse belonging to the hypostasis or person as such cannot be multiplied, because it is impossible that one thing not have one esse.
• Counterfactual: if human nature came to the Son of God accidentally, as some posit, there would be two esse, as in Socrates one esse by which he is white and another by which he is man. But to be headed, bodily, animated all pertain to the one person of Socrates, so from all of these there is only one esse in him.
• Boundary case: if after the constitution of Socrates’ person he acquired hands, feet, or eyes (as happens to one born blind), no new esse would accrue, only a relation to these, since he is said to be according to what came later as well.
• Conclusion: human nature being joined hypostatically, not accidentally, no new personal being accrues to the Son, only a new relation of the pre-existing personal being to the human nature — so that the person is said to subsist according to the human nature too.

6. The soul-body comparison, and a student’s objection (“You’d be monophysite if you said there was fully immersed”) #

He compares: the esse of the human soul does not depend on the body (Aristotle “perhaps one of the first to show” it). Plato saw this too, but for Plato the body was like clothing for the soul, so Platonists have a hard time explaining the unity of man. Rather, the body partakes of the existence of the soul; analogously the human nature partakes of the existence of God — “I gotta be kind of careful, it’s not exactly the same thing.” Christ has one being simply, which he had before he took human nature to himself. Likewise before the resurrection the soul has an existence the body will be drawn to and partake of.

• Aristotle’s reasoning: understanding the universal is not in the body, so the soul has an operation not in the body; therefore its existence is not immersed in the body — if its existence were only in the body, its operation would be only in the body. Hence (De Generatione Animalium) the human soul does not come from mother and father. He thanks God for his soul, given immediately, and for his body, given through his parents.
• Aside on gratitude: thank God for choosing you to be — not because you were better than others; it is gratuitous and merciful. “If he hadn’t chosen me to be, I’d be nothing.” A priest’s joke: he didn’t choose you because you’re good-looking, because you’re not.
• Student: may we say that just as the soul is not fully immersed in the body, the divine nature is not fully immersed in the human nature? His answer: no — soul and body nevertheless form one thing, whereas the two natures do not come together to form one nature; that would be the monophysite heresy. The Athanasian Creed makes the comparison of incarnation with soul and body; but in the Summa Contra Gentiles Thomas explains Christ’s human nature as a joined tool of his divinity — not so much form and matter as agent and tool.

7. The four replies of a. 2 (“it more retains unity according to unity of the hypostasis”) #

1. Esse follows the nature not as having esse but as that by which something is; it follows the person as the one having existence — so unity of hypostasis wins out over duality of nature.
2. The eternal existence of the Son, which is the divine nature, becomes the existence of the man, inasmuch as human nature is taken up into the unity of the person — as the body shares in the existence of the understanding soul, which has existence in its own right (not true of other forms in matter).
3. In the divine persons the person is the same as the nature, so there is no esse of the person apart from the esse of the nature; hence one esse for three persons. They would have a threefold esse if in them the esse of the person differed from the esse of the nature.
4. The soul gives esse to the body inasmuch as it makes it animated and in act; but the whole composed of soul and body, as signified by “humanity” or “human nature,” signifies not that which is but that by which something is. So what there is, is the esse of the subsisting person as having a relation to such a nature — of which relation the soul is the cause, inasmuch as it perfects human nature by informing the body. (He reads this reply twice, as hard.)

8. Digression: why obey God, why love God (“Maybe the best reason for obeying God is because you love God”) #

He notes the oddity that three persons have only one will — no disagreement, no conflict of wills, and no obedience “up there.” Then: why should we obey God? Ladder of reasons — punishment if you don’t; reward if you do; best, because you love God (“if you love me, keep my commandments”), since because you love someone you do their will. Why love God? The five chapters of the Summa Contra Gentiles on the goodness of God: God is good (the good is to be loved); God is goodness itself (nothing else is good except by partaking of him, so the very reason anything is desirable is God); nothing bad in God, so there is no reason not to love him; God is the good of every good; God is the summum bonum. Add: he chose me to be, created my soul, gave me my body through my parents, gave me parents, brothers, teachers. Parallel in the Act of Contrition: “because I dread the loss of heaven and the pains of hell… but most of all because they offend thee” — lesser reasons rising to the highest. Aside: some don’t love God because he opposes what they want to do, but there is no reason in God not to love him.

9. Proemium of q. 18: six articles on the will (“kind of thorough investigation here of the will of Christ”) #

1. Whether the divine will and the human will in Christ are other. 2. Whether in Christ’s human nature the will of sensuality is other than the will of reason (he flags voluntas sensualitatis as a strange term, to be left for now). 3. Whether on the side of reason there were many wills in Christ — this arises from “not my will but thine be done”: he conforms himself to God’s will, yet something in his will is opposed to the suffering, a duplicity “not in the bad sense.” 4. Whether there was free judgment in Christ. 5. Whether his human will was altogether conformed to the divine in what was willed. 6. Whether there was any contrariety of wills in Christ.

10. Q. 18, a. 1: the four objections to two wills (“A will is something personal, very personal”) #

1. The will is the first mover and commander in each one doing; in Christ the first mover was the divine will, since all human things in Christ were moved according to it. (His gloss: if the human will is wholly conformed, the divine will can be first mover — but there is still a second mover.)
2. An instrument is not moved by its own will but by the will of the mover; Christ’s human nature was a tool of his divinity (his text cites Damascene).
3. Only what belongs to nature is multiplied in Christ; but will does not seem to pertain to nature, since natural things are of necessity and the voluntary is not necessary. (His gloss: they distinguish nature and will as causes — nature is determined to one, will is open to opposites.)
4. Damascene, third book: in some way to will is not of nature but of our own understanding, i.e. personal; but every will is some kind of will, since what is not in a genus is not in one of its species (reference to Aristotle’s Topics). So every will pertains to a person; one person, therefore one will.

• A student notes the fourth objection seems to follow on the third; he agrees.

11. Aside on translation (“A little mistake at the beginning is a great one in the end”) #

The footnotes render proemium as “introduction”; the Vatican II English translation did the same. Talk of the translators — Gregory Baum, Abbott, Flannery — of a man who did his novitiate at “our monastery up in Nova Scotia” and later left the Church, and of the English in the blue volumes needing to be redone. He quotes: verbis inordinate prolatis incurritur haeresis [unclear in recording; his rendering: disordered words run into heresy]. Also: a minister is an “animated tool,” a different sense of tool.

12. Sed contra (“not my will, but yours, come about”) #

Luke 22: “Father, if you wish, transfer this chalice from me; but truly, not my will but yours be done.” Ambrose, in the book to the emperor Paschasian [ed.: likely Gratian]: “just as he took on my will, he took on my sadness”; and on Luke: he refers his own will to the man, and the Father’s to the divinity — the will of man is temporal, the will of the divinity eternal.

13. The body of a. 1: the history of the error, then the reason (“they seem to have been what moved” in diverse ways) #

Some posited one will only, moved to it in different ways:

• Apollinaris: no understanding soul in Christ, the Word in place of the soul or intellect (taking “the Word was made flesh” as flesh and body only). Since the will is in reason (De Anima III), there would be no human will, so only the divine.
• Eutyches and those positing one composed nature (monophysites — physis is Greek for nature) are forced to place one will in that one nature.
• Nestorius: the union of God and man made only according to affection and will — then Christ would be just a man, and the one will is the human. He notes the three positions are arranged as: only divine, a composite, only human.
• Macarius of Antioch, Cyrus of Alexandria, Sergius of Constantinople (“three big cities”) and followers: two natures united according to the hypostasis, but one will, since Christ’s human nature was never moved by its own motion but only as moved by the divinity — “as is clear in the synodic epistle of Pope Agatho. I’m sure you’re all thoroughly familiar with that.” His text cites the Third Council of Constantinople.
• The sixth synod at Constantinople determined two wills: “as of old the prophets taught about Christ, and he himself instructed us, and the symbol the Holy Fathers handed down — there are two natural wills in him and two natural operations; this we proclaim.” Then Thomas’s own reason: (1) the Son of God assumed a perfect human nature; (2) to the perfection of human nature pertains a will, a natural power of it, just as intellect or reason is; (3) so he took on a human will in his human nature; (4) and by assuming human nature the Son underwent no lessening in what pertains to his divinity — he did not become less divine by becoming man, and to God it belongs to have a will. Therefore two wills.
• His own remark: he has never personally had difficulty accepting two wills in Christ; it is implicit in saying he is true God and true man. A student: the trouble is a consequence of a problem in understanding the incarnation itself — he agrees.

14. The replies of a. 1 (“he moves the will, not violently, but to freely will something”) #

1. Everything in Christ’s human nature was moved by the motion of the divine will; it does not follow that there was no proper motion of the human will — the wills of the pious, i.e. of the other saints, are also moved according to God’s will. Philippians 2:13, “who works in us both to will and to perfect” — “Thomas is always quoting this”; also the Old Testament text that the will of the king is in the hand of God, who turns it when he wants. God moves the will not violently but to freely will something. The very point Thomas makes: the will cannot be moved inwardly by any creature — even the devil can only tempt, persuade, seduce — but it is moved inwardly by God. So Christ according to his human will followed the divine will: “that I might do your will, my God.” Augustine Contra Maximinum: those words show his will subject to the Father — as if we denied that the human will ought to be subject to God’s will. “As Saint Paul says, not me, but the grace in me.”
2. It belongs to an instrument to be moved by the principal agent, but in diverse ways according to the properties of its nature. Three-step example: the inanimate instrument (axe, saw) is moved by the artist through bodily motion only; the instrument animated by a sensing soul is moved by sense desire, as the horse by the rider; the instrument animated by an understanding soul is moved through its own will, as the servant by the master’s command — and the servant is an animated tool, “as the philosopher says; Aristotle first made this distinction.”
3. The power of will is natural and follows the nature necessarily; but the act, also called “the will,” is sometimes natural and necessary — as regards happiness (“you don’t choose to be happy or to be miserable”) — and sometimes comes from the free judgment of reason and is neither necessary nor natural; yet reason itself, the beginning of that motion, is natural. So a human will must be placed in Christ not only as a natural power and a natural motion but as a motion of reason.
   • Digression: Shakespeare’s definition of reason, “the ability for a large discourse, looking before and after” — a definition of reason as reason. For most of our understanding is reasoned-out understanding, which comes after reasoning; but if you understood nothing before reasoning you would have nothing to reason from (a student: “I know the whole is greater than the part”). So there must be natural understanding before reasoning, and Shakespeare distinguishes reason as a nature from reason as reason. Reasoning is more known to us — “things in motion sooner catch the eye than what not stirs” — and discourse comes from the Latin for running, so reason gets its name from its running from one thing to another.
   • Proportionally for the will: one might define it as “the ability to choose,” which is more known to us; but could the will choose if it did not will something without choosing? You choose with a view to an end, so something must be willed naturally as end, and then by the liberum arbitrium of reason you choose this or that way to your goal. Aristotle on choice in the Nicomachean Ethics: it is like an act of will and an act of reason, because it involves both — hence motus rationalis; he will return to this at the article de libero arbitrio. Still, the very ability to choose belongs to man because of his nature.
4. To say one wills “in some way” designates a determined mode of willing; and the mode is placed about the thing of which it is the mode. Since will pertains to nature, willing in a certain way pertains to the nature — not considered absolutely, but as it is in such a hypostasis. So Christ’s human will had a determined mode from being in the divine hypostasis: it would always be moved according to the motion of the divine will.

15. Closing question (“Could Christ sin?”) #

People ask it. His answer: “I don’t think so.” Asked whether Christ chose not to sin: “No. Be careful about that.” Then a break. [He does not develop this; left as it stands.]

His words #

• unum / “two” said simply vs. secundum quid — without qualification vs. with a qualification (“two in nature”).
• alterum — diversity of accident suffices; aliud — requires diversity of substance, i.e. of suppositum.
• “the fifth book of wisdom,” “the fourth book of wisdom” [ed.: Aristotle’s Metaphysics].
• “to be” / “one to be” / “one existence” [ed.: esse].
• “convertible” — as a thing and its definition, or a thing and its property in the strict sense.
• “hypostatic union” — two natures not becoming one nature, united in one hypostasis subsisting in both.
• “that which has existence” vs. “that by which something has existence” — hypostasis vs. nature.
• “joined tool” — the human nature of Christ as instrument of the divinity (from Summa Contra Gentiles).
• voluntas sensualitatis — “will of sensuality,” which he calls a strange term.
• physis — Greek for nature; whence “monophysite.”
• “animated tool” — the servant, as against the axe (inanimate) and the horse (moved by sense desire).
• “reasoned-out understanding” vs. “natural understanding” — after reasoning vs. before it.
• motus rationalis — the motion of reason in willing; liberum arbitrium — free judgment.

Texts #

Read in class

• Thomas Aquinas, Summa Theologiae III, q. 17, a. 1, ad 5, ad 6, ad 7
• Summa Theologiae III, q. 17, a. 2 (objections, sed contra, body, four replies)
• Summa Theologiae III, q. 18, proemium (the six articles)
• Summa Theologiae III, q. 18, a. 1 (objections, sed contra, body, four replies)
• Luke 22:42; Philippians 2:13
• Decree of the Sixth Council (Constantinople) on two natural wills and two natural operations, as quoted in the article

Mentioned

• Aristotle, Metaphysics V (substance as nature and as suppositum); Metaphysics IV, beginning (being as being, one and many)
• Aristotle, De Anima III (the will is in reason); Topics (what is not in a genus is not in its species); De Generatione Animalium (the human soul not from the parents); Nicomachean Ethics (choice)
• John Damascene, De Fide Orthodoxa III
• Thomas Aquinas, Summa Contra Gentiles (five chapters on the goodness of God; human nature as joined instrument); Commentary on the Sentences (objection on being, one, good, true); Summa Theologiae I (unity of God; God has a will; the will moved inwardly by God); Summa Theologiae I-II (“the second part,” on the will)
• Augustine, Contra Maximinum; Ambrose, to the emperor Paschasian [ed.: likely Gratian], and on Luke
• The Athanasian Creed; the synodic epistle of Pope Agatho; Third Council of Constantinople
• Shakespeare: “large discourse, looking before and after”; “things in motion sooner catch the eye than what not stirs”
• Vatican II translations (Baum, Abbott, Flannery)
• Apollinaris, Eutyches, Nestorius, Macarius of Antioch, Cyrus of Alexandria, Sergius of Constantinople

His questions #

• Can it be said simply that Christ is two? No — only secundum quid, two in nature; predication is of the suppositum, and there is one suppositum.
• What does “convertible” mean? That the terms can be turned around, as a thing and its definition, or a thing and its property in the strict sense.
• Is there one esse in Christ or two? One simply, because esse belongs to the hypostasis as that which has existence, and human nature was assumed hypostatically, not accidentally.
• If the soul is not fully immersed in the body, is the divine nature not fully immersed in the human? (student) No: soul and body form one thing, whereas the two natures do not make one nature — that would be monophysitism.
• Why should we obey God? Best, because we love him; and we should love him because he is goodness itself, the good of every good, and has nothing bad in him.
• Are there two wills in Christ? Yes: he assumed a perfect human nature, of which will is a natural power, and his divinity was in no way lessened.
• Does the instrument’s being moved by another exclude its having a will? No: instruments are moved according to the properties of their nature — the axe bodily, the horse by sense desire, the servant through his own will.
• Is there understanding before reasoning? Yes, natural understanding — if you understood nothing before reasoning you would have nothing to reason from.
• Could Christ sin? Did he choose not to sin? “I don’t think so”; and no, he did not choose not to sin — “be careful about that.” Left undeveloped.