Right at the start of his treatment of the Trinity Aquinas identified subsistent relation as the key concept in identifying and distinguishing the Persons of the Trinity. In the light of the material that he has developed since that introduction, he now returns to consider in greater depth the comparison of the Persons and the relational properties.
The Thread of the Argument
A1: Returning immediately to the theme of Question 28, Aquinas asks whether the relations in the Godhead can be identified with the Persons of the Trinity. The reason that he returns to this question is that he wants to address some of the possible problems and alternative approaches to the relational understanding of the Trinity, in the light of the theory that he has developed in the body of the treatise. Here Aquinas can recall that since the essence is the same as each Person (Question 39, Article 2) and each relation is necessarily the essence, we can identify the relations with the persons. Aquinas can apply the reasoning of this latter question to conclude that the relative properties are in the Persons and yet they are the Persons. In this way, Aquinas both argues against those who would attempt to drive a wedge between the relations and the Persons as well as preparing the ground for his contention in the next article that what distinguishes the Persons is founded in their relational properties rather than in what founds the relations.
The first objection suggested that if two things are the same, then the multiplication of one would imply the multiplication of the other. This would seem to rule out there being more than one relation in one Person; troubling if we reflect upon the paternity and common spiration in the Father. The answer to this objection allows Aquinas to amplify the point made in his reply: Person and relative property signify the same reality but differ conceptually. God’s simplicity excludes any composition of form and matter (therefore the abstract is to be identified with the concrete in God) and it excludes any composition of subject and accident (therefore any real attribute of God is His essence). The former means that, for example, God’s deity is God and it also implies that the Paternity of the Father is the Father: the relative properties and the Persons signify the same reality although their modes of signifying differ. The two identities together imply the identity of Person and relational property. The multiplication suggested in the objection need not happen: for example, the common spiration is not a single person subsisting per se but one property existing in two Persons in a way similar to the existence of one essence in two Persons (as seen in Question 30, Article 2).
The fact that Person and property signify the same reality and yet differ in their mode of signification allows us to understand that the relations determine distinct Persons in the Godhead yet do not determine distinct essences in the Godhead. The relational properties are only “in the essence” of God via this identity of Person, essence and relation; their signification only operates when considered as signifying something like a form in a subject.
A2: When we think of created things, and particularly when we thing about created things through the lens of Aristotle’s division of being into the categories, it’s hard to see that the relations are fundamental to the distinction between the Persons. In the Categories, being is divided into “substance” and the nine accidental categories, one of which is “relation”. This division implies that substance is, in a sense, primary and that relation is secondary: in this case, relation would appear to pre-suppose a distinction between substances. However, if we try to apply this reasoning to the relations in the Godhead and to the essence of God Himself, we have to be careful; the relations in the Godhead are subsistent and each the same as the essence. Putting this informally, we might ask whether God the Father is Father because he begets the Son or whether he begets the Son because He is Father. In contrast to other theologians of his day (Bonaventure, for example), Aquinas takes the latter view. The relational property of being Father is the primary source of what makes the Father a distinct Person; the fact that the Father is the originator of the Son and that the Son originates from the Father is secondary to the relational properties of being Father and of being Son.
In order to argue in support of this position, Aquinas identifies that the only possibilities for distinction in the Godhead arise from either origin or relation. There is in the Godhead, of course, no real difference between these, but they differ by their mode of signifying: origin signifies in the mode of an act and relation signifies in the mode of a form. In the created world, relation follows upon act, therefore Aquinas’s intellectual opponents apply this to the Trinity and argue that, for example, the Father is distinct from the Son because the one generates and the other is generated and that the relations follow after the fact. Aquinas identifies two major faults with this position.
The first problem is that in order to identify two things as distinct it is necessary to identify something intrinsic to them that provide a foundation for the distinction. Origin simply does not supply that intrinsic property, rather being a sort of trajectory from a thing to a thing that presupposes a distinction between them. Actually within a divine Person there are only two candidates that might provide the distinction: essence and relation. The former doesn’t distinguish, so it must be the latter that does. This line of reasoning explains Aquinas’s insistence in the first article that the relations are in the Persons.
The second problem is that positing the origins of the Persons as fundamental to the distinction between the Persons is prone to lead to the error of dividing something common to the three Persons. In other words, this approach leads to the idea of dividing the substance and therefore to tritheism.
A3: Even if we grant that it is the relations that make the Persons, is it possible that we might abstract the notion of relation from the notion of Person and still maintain a distinction between what would simply be hypostases of the Trinity? No: Aquinas insists that even when we are considering things as abstracted intellectually (as opposed to what is truly in reality) relation remains necessary for the distinction of the Persons. If we abstract away relation in our thinking, then Person evaporates from our thinking as well.
Aquinas considers how we make abstractions and identifies two fundamental types. When we consider a man as a rational animal, if we abstract the idea of rational from man and then remove the concept of rational, then we no longer have the concept of man but only the idea of animal. This example involves the abstraction of a universal from particulars. In contrast, if we consider the example of abstracting from a matter/form composite such as a bronze ring, abstracting and then removing the idea of a ring or circle still leaves us with bronze as a concept in the mind.
When we consider God, there are no universals and particulars and there is no composition of matter and form, but there remains the analogue of them by means of the different modes of signifying. Corresponding to the example of particulars and universals, abstracting and removing the properties leaves the common essence of God but not the hypostases which are analogical to particulars. When the properties that do not constitute the Persons are abstracted and removed in the sense of the matter/form abstraction, the concept of hypostasis remains. However, if the properties that constitute the Persons are removed, the concept of hypostasis vanishes. The point is that as the relational properties are subsistent, they “bring along with them” their corresponding supposits. One simply cannot be thought of without the other.
Those that argue that origin provides the foundation for relation might suggest that one can therefore abstract away the notion of relation whilst still leaving origin as the basis for the hypostases. However, in the first place Aquinas has shown the weakness of this position in the previous article and secondly since every hypostasis with a rational nature is a Person (following Boethius) it would be necessary to abstract way the rationality of the nature rather than the properties constituting the Person in order to be left with a hypostasis which is not a Person.
A4: In asking whether the characteristic (or notional) acts such as begetting and spirating are presupposed by the relations, Aquinas has the chance to summarize and elaborate upon his teaching from the earlier articles and the opportunity to distinguish between reality and how we may conceptualize that reality. Here he explicitly mentions the two possibilities: either the Father is the Father because He generates or the Father generates because He is Father. Aquinas favours the latter, but he is willing to make conceptual distinctions that explain the structure of the problem and the approach of other theologians.
Assuming that the relations in God really constitute the Persons and make them distinct then we can observe that origins in God can be signified actively (e.g. generation or spiration) or passively (e.g. being begotten or proceeding). This distinction allows us to observe that the origins as passively signified are conceptually prior to the properties of the Persons who proceed. When origins are signified actively, they are conceptually prior to any non-constitutive property of the Person. For example, the characteristic act of the common spiration is conceptually prior to un-named relation common to the Father and the Son. So in the conceptual realm, when we think of what constitutes the Person of the Father we can think in terms of a relation that presupposes the characteristic act of begetting but we can also think in terms of the relation constitutive of the Father being presupposed by the characteristic act. This process of distinction mirrors the conceptual distinction that one might make between the word “Father” signifying the divine relation of paternity and the subsistent Person.
- The relations constitute and distinguish the divine Persons.
- Person and property signify the same reality but differ in their mode of signification.
- “God the Father begets the Son because He is Father” rather than “God the Father is Father because he begets the Son.”
- We cannot abstract the idea of relation from the divine Persons in order to leave some kind of bare but distinct hypostases.
- Distinctions can be made facilitating the conceptual priority of the characteristic acts over the relations.
- Question 40 has gained the reputation of being one of the hardest questions to understand in the summa. Emery quotes Dondaine as saying that it considers “the most arduous problems in Latin Trinitarian theology”.
- Aquinas’s conclusions in this question represent one side of an enduring split in Western theology between what one might approximately characterize as a Dominican school and a Franciscan school.
- Article 4 appears to make distinctions between the real and our conceptual understanding of the real that almost contradict one another.