Up to this point in Book 3 Richard has told us several things about love (caritas). We have wondered at his saying there isn’t a perfectly good person if he doesn’t love. We have sorted through some necessary conditions for love such that we wonder whether a perfectly good person p must love another person q if p is to be perfectly good. You might say we’ve been contemplating some divine ethics, or aesthetics, or whatever.
In the previous post I suggested how we might interpret what Richard means by saying (two) divine persons are equal and similar to one another, namely the divine persons have the same disposition of love and the same acts of love (see [T4’] and [T5’]). In the next part of Richard’s argument he returns to his metaphysics of the divine substance which he discussed in Books 1 and 2. (In the English translation the term ‘plenitudo’ is translated as ‘fullness’, which might be misleading because it is a technical term in contrast with ‘participation’ (participatio). So I stick with ‘plenitude’.) In Book 3.8 Richard reminds us that
R1: In mutually loved and mutually loving persons, in order that supreme love might exist worthily, there must be in each both supreme perfection and the [plenitude] of all perfection.
In Book 1 Richard distinguished between ‘plenitude’ and ‘participation’.
R2: If p has a plenitude of X, then p has X independently of all other substances.
R3: If p has a participation of X, then p has X dependently on another substance.
Think of the plenitude of X as the original X, and participation as contingently having a likeness of X. So,
R4: If each divine person p and q has the plenitude of supreme love, then p and q have supreme love independently of any other substance.
In Book 1 Richard argued that there can be only one substance that is eternal and causally depends on no other substance; all other existing substances are either sempiternal (roughly co-eternal) causally from another substance (e.g., angels), or temporal and causally from another substance (all material creatures); there is no substance that is temporal and not causally from another substance.
Given R1, R2, and R4, it looks like there are two persons that have numerically the same substance. But what level of generality or individuality is this substance? Some (Aristotelian secondary) substances are quite general like animal, and some are quite specific like human. Even still, there are individual humans like Dale, Joseph, and JT. So, on what level ought we to take the divine substance? Well, none of these. Instead, in Book 2.12, which I consider to be one of the most overlooked and under-appreciated sections of Richard’s De Trinitate, he declares that some substances by definition are singular, non-repeatable, non-instantiable (I explain ‘instantiable’ and ‘non-instantiable’ a bit more in the next post). That is, if we consider the person Daniel, he is constituted by the substance Danielitas (Richard borrows from Boethius’s Platonitas). If a person is constituted by Danielitas, then he is the person Daniel. Having made this distinction Richard applies it to the divine substance by calling it divinitas. If a person is constituted by divinitas, then he is a divine person. (I return to the ‘constitution’ issue in the next post.) Notice that divinitas is a substance and there cannot be further instantiations of it. So, the two divine persons (at this point in the argument) have numerically the same singular substance called divinitas.
Next Richard gives us some rhetorical helps. Consider a human person. On Richard’s view she is composed of two substances: a bodily substance and a rational substance, and yet she is one person. Why think it impossible then if in God there is one substance and yet more than one person? Crazier things happen….
“Explain to me, I implore you, how there is personal unity in so great a dissimilitude and diversity of substances, and I will tell you how there is a substantial unity in so great a similitude and equality of [divine] persons. You say, ‘I do not grasp it; I do not understand; but even if the understanding does not grasp it, nevertheless experience itself per suades me.’ Well said indeed and rightly too! But if experience teaches you that something exists in human nature that is above understanding, should it not also have taught you that something exists above your understanding in divine nature? And so a person can learn from himself, by way of opposites as it were, what he ought to think concerning those things which are proposed to him for believing concerning his God.” (Book 3.10)
Before moving on to Richard’s initial argument for why there must be a trinity and not a duality of divine persons based on what he takes as the nature of perfect love I want to mention one hitherto overlooked issue in contemporary Trinitarian discussions. This issue will certainly be discussed after this current series on Book 3 of Richard’s De Trinitate. That is, Richard’s apparent constitutional Latin trinitarianism [= CLT] which I take as a different stream of Latin trinitarianism than the one Brian Leftow has called “a Latin Trinity” or “the Latin Trinity”. I take Richard and those who rightly interpret him or agree with him (e.g., Henry of Ghent and Duns Scotus) to follow CLT, but those who are less interested in Richard’s own view or just misinterpret him to satisfy Leftow’s LT, or what I would call non-constitutional Latin trinitarianism [= NCLT]. If this is right, as I believe it is, then Brower and Rea have some new (non-Dominican) comrades.