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A PUZZLE ABOUT DIVINE PERSONHOOD IN DE TRINITATE, VII AND VIII

Nathaniel E. Bulthuis

In the second half of book 7 of Augustine’s De Trinitate, Augustine addresses a certain

puzzle about the God of Christianity, concerned with the nature of divine personhood.1 God is

claimed to be three persons, but that multiplicity of persons seems incongruous with the

simplicity of the divine essence. Any adequate articulation of divine personhood, then, must

respect that simplicity. Though it can handle aspects unique to each divine person, the logical

apparatus Augustine develops in book 5 of De Trinitate is unable to explicate the nature of

divine personhood itself, and so provide a solution to this puzzle. This inability to provide a

proper understanding of divine personhood leaves Augustine searching in book 7 for another sort

of explanation of divine personhood. However, while some progress is made, Augustine does not

discover an adequate explanation of it in that book.

Yet Augustine does not abandon his search for a solution to this puzzle at the end of book

7.2 Rather, at the conclusion of that book, he provides a diagnosis of why our attempts to

1 The content of this puzzle is set out earlier in the work, in book 5. But Augustine gives no indication there that

there is in fact a puzzle to be solved, rather than merely a problem of Nicene trinitarianism to be tolerated. See Aug., trin., V,9,10.

2 This fact seems to me to have gone largely unnoticed in the literature, evidenced by the way in which the structure of the work is typically viewed. Though individual accounts vary, a feature common to many is that book 7 is regarded as part of a unit of the work distinct from that unit to which book 8 belongs. Edmund Hill, for example, argues that books 1-7 and 9-15 constitute the two main parts of De Trinitate, book 8 serving as a transitional book. See E. Hill (cur.), The Trinity, New City Press, Hyde Park, New York 1991 (The Works of Saint Augustine, 5), 18-27. That books 1-7 constitute a major unit of the work is echoed by Luigi Gioia, who argues that ‹‹the treatment of books 1 to 7 as a single unity is crucially important for the correct interpretation of Augustine’s doctrine of the Trinity›› (L. Gioia, The Theological Epistemology of Augustine’s De Trinitate, Oxford University Press, New York 2008, 24). See also H. Chadwick, Augustine, Oxford University Press, New York 1986, 91; B. Studer, Augustins De Trinitate. Eine Einführung, Ferdinand Schöningh, Paderborn 2005, 79. Others have argued (correctly, in my opinion) that books 1-4 and 5-15 constitute the two major units of the text, the former devoted to providing a biblical foundation for a Nicene formulation of the Christian faith and the latter devoted to a philosophical justification of that formulation. See E. Hendrikx, Introduction in M. Mellet-Th. Camelot (cur.), La

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understand divine personhood have so far failed, and a call to intellectual ascent by which that

failure can be overcome. Book 8, informed by this diagnosis, undertakes that very process of

ascent, a process which results in Augustine’s fascinating investigation of the human mind in the

latter books of De Trinitate. Book 8 thus continues the search for a solution to a puzzle about

divine personhood articulated in book 7, and so constitutes a further step in an inquiry into the

nature of divine personhood itself. As a consequence, the investigation into the nature of the

human mind that begins in book 9 is itself part of that larger theological inquiry. There are

important lessons to be drawn from this consequence, two of which I highlight.

1. Augustine on Relative Predication

To understand what is at issue at the end of book 7, we need first to look earlier in the

work, to the philosophical conclusions of book 5. In that book, Augustine considers an Arian

objection to a trinitarian conception of God.3 Augustine’s interlocutors argue that

whatever is said or understood about God is said not according to accident but according

to substance. Accordingly, to be unbegotten is [said] of the Father according to substance,

and to be begotten is [said] of the Son according to substance. However, to be unbegotten

and to be begotten are different. Therefore, the substance of the Father is different than

Trinité, Institut d’etudes augustiniennes, Paris 1955 (Oeuvres De Saint Augustin. Texte De l’Edition Benedictine, 15), 17-21; G. Matthews (cur.), On the Trinity, Books 8-15, Cambridge University Press, New York 2002, ix-xii. But accounts of this sort still regard books 5-7 and 8-15 as distinct sub-units of that second unit. A consequence of my argument for both sorts of accounts is that a strong division between books 7 and 8 can no longer be maintained. What I think this suggests is that the typical motivation for structural analyses of this sort – that book 5-7 are directed towards a project distinct from that of books 8-15 – is at least to some extent misguided. My own view is that we find in books 5-15 a largely unified philosophical inquiry into the divine Trinity, motivated by a series of interconnected and increasingly difficult puzzles about that Trinity. (For a third sort of analysis, according to which the work divides into three distinct units – books 1-4, 5-7, and 8-15 – see G. Madec, “Inquisitione proficiente”. Pour une lecture “saine” du De Trinitate d'Augustin, in J. Brachtendorf (cur.), Gott und sein Bild. Augustins De Trinitate im Spiegel gegenwärtiger Forschung, F. Schöningh, Padeborn 2000, 61-8; E. Bermon, Analyse du “De Trinitate” de Saint Augustin in M. Caron (cur.), Saint Augustin, Éditions du Cerf, Paris 2009 (Les Cahiers d'Histoires de la Philosophie), 53-76).

3 On the Arian context of the argument, see M. Barnes, De Trinitate VI and VII: Augustine and the Limits of Nicene Orthodoxy, ‹‹Aug. Stud.››, 38 (2007), 189-202.

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that of the Son.4

Augustine agrees with his interlocutors that nothing can be said of God according to accident.

We can truly predicate nothing of God accidentally because such predication requires that its

subject is capable of change. Thus ‘unbegotten’ and ‘begotten’ cannot be predicated accidentally,

for that would entail that that of which each is predicated is something changeable, something

Augustine rejects because ‹‹there is nothing in [God] that can be changed or lost››.5 Augustine’s

Arian interlocutors conclude, then, that everything must be predicated of God according to

substance, such that a given predicate expresses not a quality of God but God himself, who is a

substance.6 And, since that substance which is God cannot be both unbegotten and begotten, the

Father and the Son must be different substances, and so not both God, who is ‹‹that unchanging

and eternal substance which is incomparably more simple than the human soul››.7

Augustine’s response to this argument is to suggest another way in which we can speak

about God. This way is what Augustine calls predication ‹‹according to a relative›› or what I will

call relative predication.8 Augustine is at pains to emphasize that this kind of predication is not

merely a kind of predication according to accident. True accidental predication requires the

changeability of its underlying subject, since the predicate expresses an accident which inheres in

its subject and so can be lost by that subject. But Augustine argues that relative predication does

4 Aug., trin., V,3,4 (CCL 50, 208): «Quidquid de deo dicitur uel intellegitur non secundum accidens sed secundum

substantiam dicitur. Quapropter ingenitum esse patri secundum substantiam est, et genitum esse filio secundum snbstantiam est. Diuersum est autem ingenitum esse et genitum esse; diuersa est ergo substantia patris et filii»

5 Aug., trin., V,4,5 (CCL 50, 209).

6 Augustine speaks of substantial predication throughout books 5-7, but he notes in his introduction to this sort of predication that, in the case of the godhead at least, it would be better if we called it essential predication, since God is not properly speaking a substance. See Aug., trin., V,2,3.

7 Aug., trin., VI,5,6 (CCL 50, 234).

8 Secundum relativum. See Aug., trin., V,4,6.

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not require the possibility of change in its subject, for what is predicated relatively of a subject is

not something distinct from that subject, but rather is an expression of that very subject, as

relative to another.9 Since the Father is God, and so eternal and unchangeable, and since ‘father’

is a term of relation, it must be said eternally with reference to another - that is, to an offspring.

God the Father, then, ensures the co-eternality of God the Son, for only in that way is God the

Father a father. The same holds for God the Son, since ‘son’ too is here a relative term. Thus,

according to Augustine, ‘Father’ and ‘Son’ are terms said neither according to accident, since

every accidental predication requires the changeability of its underlying subject, nor according to

substance, since each is said of a subject not with reference to that subject itself but rather with

reference to another. Instead Augustine argues that they are predicates of a kind distinct from

either of these two, such that God the Father is, and must be, eternally related to God the Son, for

only in that way is the former a father and the latter a son.

Augustine uses the distinction between relative and substantial predication to distinguish

between those things which are uniquely said of either the Father, the Son, or the Holy Spirit,

and those which are said singularly of the godhead, and so commonly of each of the divine

persons.10 ‘Unbegotten’ and ‘begotten’, to return to the predicates initially at issue, are each said

uniquely of one of the divine persons and are, consequently, relative terms. Augustine employs

this distinction in books 5 through 7 to help us understand how it is, and so to provide a defense

9 Augustine argues that something can be predicated relatively only of God, since ‹‹in created and mutable things

what is not said according to substance can only be said according to accident›› (Aug., trin., V,4,6 (CCL 50, 210)). However, Augustine does seem to suggest later in the text that something can be said relatively of a creature as well (see infra note 14). Perhaps we can distinguish between an improper and a proper sense of relative predication. Predicating a term such as ‘father’ of a creature is improperly called relative predication, since such predication is in fact a kind of accidental predication. Predicating that term of a divine person, however, is properly called relative predication. Yet, because of a shared logical character, improper relative predication can serve to explicate for us the nature of proper relative predication.

10 See Aug., trin., V,8,9; V,11,12.

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of the claim that, some given feature is peculiar to one of the divine persons alone without

abandoning the simple unity of the divine being. Relative terms are predicated of a subject but

with reference to another (ad aliquid), not with reference to that subject itself (ad se), and so,

argues Augustine, predicates said of one of the divine persons alone do not in any way threaten

the unity and simplicity of that being to which each of the divine persons is identical.11

But left unanswered so far is the perhaps more profound issue of the nature of the subject

of such predicates - that is, the nature of a divine person himself. Unlike terms uniquely said of

one of the divine persons, ‘person’ itself can be said univocally of each divine person. And yet,

unlike all other terms said univocally of each divine person, it cannot be said singularly of the

godhead. God is, after all, not a person but three persons. So it seems that ‘person’ expresses

something quite unlike the terms of either sort that we have considered so far. An adequate

articulation of what this predicate expresses is the project Augustine begins in the second half of

book 7, and it is, I argue, the dominant project of the rest of the work. In the next section, then, I

want to look closely at the second half of book 7 itself, both to motivate the claim that this is

indeed the issue that Augustine is concerned with there and to see how the end of book 7 serves

as a foundation for the philosophical inquiry Augustine conducts in book 8.

2. Initial Analyses of the Puzzle in Book 7

At first glance, Augustine seems to suggest in the second half of book 7 that Latin

orthodoxy’s use of the term ‘person’ is motivated less by principle than by pragmatism.

Augustine writes that the Latin church has agreed to say that there are three persons ‹‹in order to

be able to say something when asked what the three are››.12 But there are two issues at play here.

11 See Aug., trin., V,11,12.

12 Aug., trin., VII,4,7 (CCL 50, 255).

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One concerns the term ‘person’ itself; Augustine readily admits that the use of that term rather

than some other is for the most part pragmatic. The other, however, is a far deeper and more

philosophically exciting issue. That issue concerns the metaphysical reality that the term ‘person’

is meant to express.

One of Augustine’s more interesting solutions in book 7 to our puzzle about the nature of

divine personhood relies unsurprisingly on his earlier distinction between substantial and relative

predication. Augustine suggests that ‘person’, like, e.g., ‘father’, is predicated not substantially

but rather relatively.

If ‘being’ is predicated substantially, and ‘person’ relatively, then we could call Father

and Son and Holy Spirit three persons in the same way as we talk about three friends or

three neighbors or three relatives with reference to each other, not with reference to

himself.13

Everything said substantially of any of the divine persons appears to be said singularly and

substantially of the godhead itself. Terms such as ‘one’, ‘being’, and ‘truth’ are said not relative

to another but with reference to the subject of which they are predicated. Since everything said

singularly of the godhead is said substantially, if ‘person’ were a relative term, this would

explain why we cannot predicate ‘person’ singularly of the godhead. For ‘person’ would not be

said with reference to the subject of which it is predicated but would rather be said relative to the

other members of the Trinity. And so, in the same way that we can say that God is Father, Son,

and Holy Spirit, without any compromise to divine simplicity, so too we can say that God is

three persons, since ‘person’, like ‘Father’, ‘Son’, and ‘Holy Spirit’, would be a relative

13 Aug., trin., VII,6,11 (CCL 50, 261-2): «Sic dicamus tres personas patrem et filium et spiritum sanctum

quemadmodum dicuntur aliqui tres amici aut tres propinqui aut tres uicini quod sint ad inuicem, non quod unusquisque eorum sit ad se ipsum»

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predicate and so not express the substance of its subject.

According to a position of this sort, divine personhood would be logically posterior to

divine essence. Relative predication depends upon some substance as its subject, as Augustine

himself acknowledges. Augustine writes in book 7 that

every being that is called something relatively is called something besides a

relative [...]. If one was not called a human being, that is some substance, there

would be nothing there that could be called master according to relation.14

But substantial predication in no way logically entails that something can be predicated of its

subject relatively, since substantial predication does not logically require that the subject of such

predication is related to some other subject. Substantial predication is therefore logically prior to

that of relative predication, for relative predication logically entails that something can be

predicated of its subject substantially, whereas substantial predication does not logically entail

that something can be predicated of its subject relatively.15 As Augustine has already admitted in

book 5, those things said uniquely of each divine person are predicated relatively. If ‘person’ too

were a relative predicate, there would then be no non-relative predicate which would serve to

mark out any of the divine persons. And so divine personhood would be logically posterior to

divine essence, for anything predicated substantially of the divine expresses only its simple

essence, and it does not logically follow that we can predicate something relatively of the divine.

Any predicate expressing divine personhood, however, will be predicated relatively, and so it

would follow that we can predicate something substantially of it as well.

14 Aug., trin., VII,1,2 (CCL 50, 247): «Huc accedit quia omnis essentia quae relatiue dicitur est etiam aliquid

excepto relatiuo [...] si non esset homo, id est aliqua substantia, non esset qui relatiue dominus diceretur»

15 Augustine would agree, I take it, that substantial predication metaphysically entails that something can be predicated of its subject relatively (at least in the case of the divine; see supra note 9).

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But Augustine is keen to defend a more robust understanding of orthodox trinitarianism,

an understanding according to which the predicate ‘person’ is as logically fundamental as any of

the predicates said of God which express his simple essence. Augustine writes of his suggestion

that ‘person’ is a relative term that ‹‹this is not how ‘person’ is typically spoken in any context;

nor in the case of the Trinity do we express anything else when we say the person of the Father

but the substance of the Father››.16 ‘Person’, then, is predicated not relatively but substantially,

and thus is said, e.g., with reference to that very substance of which ‘Father’ is predicated.17 To

say that God is three persons is to say of God himself that he is three unique substances, even

though he is only one being, one essence, one substance.18 So the distinction between substantial

and relative predication will not serve to fully illuminate for us the metaphysics of divine

personhood, and we do not yet have a solution to the puzzle which motivates our inquiry.19 But it

does advance that inquiry, since our conclusions here entail that there is at least one predicate

predicated substantially of each of the Father, the Son, and the Holy Spirit which cannot

moreover be predicated singularly of the godhead. And so at least Augustine’s task is made

clearer – it is to provide for himself and for his readers a way of understanding a being that is not

16 Aug., trin., VII,6,11 (CCL 50, 262): «Sed neque persona ita dici alicubi solet, neque in hac trinitate cum dicimus

personam patris aliud dicimus quam substantiam patris. Quocirca ut substantia patris ipse pater est, non quo pater est sed quo est; ita et persona patris non aliud quam ipse pater est. Ad se quippe dicitur persona, non ad filium uel spiritum sanctum; sicut ad se dicitur deus et magnus et bonus et iustus et si quid aliud huiusmodi. Et quemadmodum hoc illi est esse quod deum esse, quod magnum, quod bonum esse, ita hoc illi est esse quod personam esse»

17 On this point, see L. Ladaria, Persona y Relacion en el De Trinitate de San Agustin, ‹‹Misc. Com.››, 30 (1972), 273-4. Others have argued that, for Augustine, the notion of divine personhood is a “relational concept.” See W.R. O'Connor, The Concept of the Person in Saint Augustine's De Trinitate, ‹‹Aug. Stud.››, 13 (1982), 137-8; also A. Trapé, I termini “natura” e “persona” nella teologia trinitaria di S. Agostino, ‹‹Augustinianum›› 13 (1973), 586-7.

18 See Aug., trin., V,1,3, where Augustine identifies God as a substance.

19 On the question of the relationship between the substantial and relative aspects of the divine persons, see Ladaria, Persona y Relacion, 275-83. See also P. Henry, Saint Augustine on Personality, The Macmillan Company, New York 1960, 23.

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just relatively but substantially three without compromising the absolute simplicity of that being.

Augustine’s response to the failure of this approach seems to be philosophical

capitulation, writing that ‹‹the reason why we do not call these three together one person […] is

that we want to keep at least one word for signifying what we mean by Trinity, so that we are not

simply reduced to silence when we are asked “three what?”››.20 But then Augustine brings his

readers back to his interlocutors’ initial question - what are these three? - and he revisits an

assumption which so far has governed his response to it. The solutions that Augustine has

considered thus far have been governed by the assumption that any adequate reply to such a

question needs to be a term of either species or genus. ‹‹So when the question is asked “three

what?” we apply ourselves to finding some name of genus or species which will comprise these

three››.21 Such an assumption seems reasonable. As Augustine notes in book 6, while ‘one’ can

be predicated of two subjects to signify sameness of being, the question ‹‹one what?››

immediately adds a qualification, and thus seems to demand a reply either in terms of a species

or in terms of a genus.22 The same appears to be true in regards to the divine Trinity; asking what

these three are immediately sets one on the task of looking for some appropriate genus or

species.

But it looks like any response in terms of species or genus is bound to fail. Earlier in

book 7, Augustine notes that a term of genus denotes what is common to a class of different

kinds of things.23 Taking ‘person’ as a generic term, ‘person’ denotes something common to the

20 Aug., trin., VII,6,11 (CCL 50, 262).

21 Aug., trin., VII,4,7 (CCL 50, 255).

22 Aug., trin., VI,3,4 (CCL 50, 232).

23 See Aug., trin., VII,4,7-8.

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Father, the Son and the Holy Spirit. But, Augustine argues, if we ought to say that there are three

persons, then we ought likewise to say that there are three beings. For the term ‘being’ too is a

term denoting something common to the Father, the Son and the Holy Spirit. But God is one

being, not three beings. Thus taking ‘person’ as a term of genus does not successfully solve our

puzzle.

But taking that term as a term of species is equally problematic. In an extended

discussion of the use of generic and specific terms later in book 7, Augustine notes that any reply

to a question about what these three are will have to be plural in nature. This fact renders

incoherent an account of divine personhood according to which ‘person’ is a term of species,

falling under some higher-order genus. As Augustine notes, ‹‹a species is not said in the plural

and a genus in the singular››.24 If ‘person’ is meant to denote a species of the divine being, then

the fact that there are three persons requires that there are also, e.g., three beings, since the term

‘being’, which denotes something common to the Father, Son, and Holy Spirit, must be a term of

the genus under which the species person falls. Whether we take ‘person’ to be a term of genus

or a term of species, then, it seems that our account of divine personhood will not solve our

puzzle, precisely because taking that term in either way fails to respect the absolute simplicity of

the divine essence.

Augustine’s initial deliberations about ‘person’ either as a term of species or as a term of

genus rested in thinking of ‘person’ as a substantial predicate, and as substantial predicates said

of the divine either as related to one another as species to genus or as both related to the Father,

the Son, and the Holy Spirit as something generically common to them. The failure of those

deliberations is what prompts Augustine to try to apply to this problem his earlier distinction

24 Aug., trin., VII,6,11 (CCL 50, 256).

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between substantial and relative predication. Such a maneuver would, if successful, both respect

‘person’ and predicates said singularly of the godhead as terms of species or genera while

avoiding the unseemly consequence that, e.g., there are three divine beings. For ‘person’ would

be a relative term, whereas, e.g., ‘being’ would be a substantial term. Consequently concerns

about singular and plural predication would be mollified by an equivocation in the kind of

predication at issue. But following the inapplicability of this distinction to the puzzle at hand,

Augustine returns to the initial assumption itself, abandoning the claim that a proper articulation

of divine personhood needs to be cast in terms of species or genera. The abandonment of this

assumption frees Augustine to look for another method according to which divine personhood

can be understood, one in which the relevant objects are understood as related to one another in a

way different than as genera, species and individuals.

3. A Different Approach to the Puzzle

Augustine’s change of tack in his inquiry is rather sudden. ‹‹Or is it like our saying that

three humans of the same sex, the same physique and the same soul are one nature››.25 It is clear

that Augustine thinks the example is beneficial as an analogy of the divine Trinity in at least one

respect. ‘Nature’ is what the ancients, lacking a term such as ‘being’, employed in its stead, and

so it seems that the types of objects in the example – humans and their shared nature – are

relevantly similar to the divine Trinity. But how is this example any different from what has been

said already? Are we not, in other words, still employing species and genera in this example?

Augustine argues that we are not. ‹‹So now we are not talking anymore in terms of genus and

species, but as if according to the same common material››.26 The analogy clearly works in one

25 Aug., trin., VII,6,11 (CCL 50, 263).

26 Aug., trin., VII,6,11 (CCL 50, 264).

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way: it has three persons (that is, three humans) all of whom have one nature, one “common

material.” If we were speaking strictly in terms of genera and species, it would seem that such an

example would be incoherent, as Augustine’s earlier considerations about generic and specific

predication suggest. For those considerations forced us to conclude that saying truly of the

godhead that there are three persons entails that there are also, e.g., three beings. The fact that the

claim that there are three humans which share one nature strikes us as felicitous suggests at least

that the terms at issue – ‘human’ and ‘nature’ – are not being used specifically or generically.

But it also appears that Augustine thinks this example, by itself, does not elucidate for us

clearly enough the kind of relationship between divine personhood and divine essence that he is

attempting to describe. For he immediately goes on to provide another possible analogy of the

divine Trinity.27 In this example, three statues subsist out of gold, and so we have three statues

and yet only one material common to them – gold.28 Augustine emphasizes that we are not

employing in this example a distinction between species and genus, nor even a distinction

between species and individuals. It is not the case, for instance, that ‘gold’ is being used here as a

generic term and ‘statue’ a specific term because ‹‹no species extends beyond the definition of its

genus››.29 In other words, if the example of the three statues depends on a distinction between

genus and species, then it needs to be the case that a statue, as a species, is defined by the

27 Augustine’s fairly quick transition to another example might be due to the fact that the example of three humans

sharing one common nature does not seem to escape generic and specific predication as successfully as Augustine needs it. ‘Nature’ appears to be a count-noun, which consequently lends itself to specific and generic predication. Augustine’s second example, which employs ‘gold’, a mass-noun, seems to avoid these worries better. Richard Cross makes a similar point. See R. Cross, Quid Tres? On What Precisely Augustine Professes Not to Understand in De Trinitate 5 and 7, ‹‹Harvard theol. Rev.››, 100 (2007), 227.

28 In his commentary on Psalm 68, Augustine explains the essential unity of the Father, the Son, and the Holy Spirit by noting that it is as «if the Father is gold, the Son is gold, and the Holy Spirit is gold» (Aug., in Psalm., 68,1,5 (CCL 39, 905)). Unlike in De Trinitate, however, Augustine gives no indication in that work that such an analogy is inadequate.

29 Aug., trin., VII,6,11 (CCL 50, 264).

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relevant genus (here gold) along with a certain differentia which distinguishes it from other

species falling under the same genus. But it is clear that statues can be constructed from material

other than gold, such as clay or marble. So ‘statue’ cannot be used here as a species term,

denoting a species of the (putative) genus gold.

It is also not the case that gold in the example is a species and the statues individuals

within that species.30 For ‹‹no species extends beyond its individuals to include something

outside››.31 In other words, a specific definition encompasses all and only the individuals

included in that definition. But, as Augustine notes, many other things besides statues are made

of gold, such as rings, and sometimes nothing at all is made out of some gold – it’s just an

unformed lump. For ‘gold’ to be a true species term requires that no further differentiae can be

made among its members. But this is clearly not true in the present case, since each golden

statue, as a statue, does not differ from the other two, and yet each differs from golden objects

which are not statues. So it seems that the relevant terms in Augustine’s example cannot be terms

of species and genera, or of species and individuals. And that seems to be just what we need,

since any interpretation of the relationship between the persons and the being of God which

employs terms of species and of genus is bound to fail.

Augustine’s examples, especially his example of the three golden statues, seem to

provide a better explanation of the divine Trinity than have any of our attempts at understanding

the nature of divine personhood in terms of a species or a genus. In the examples Augustine

provides, the mere fact that there are three objects of a particular kind, be they humans or statues,

30 Augustine had earlier in the text quickly considered, and just as quickly rejected, the proposal that ‘being’ is a

specific term and ‘person’ a term for an individual. Augustine is thus paralleling this example with the relations of genus, species, and individual that he had considered earlier in the text, in order to show that it is unlike any of those relations. See Aug., trin., VII,6,11.

31 Aug., trin., VII,6,11 (CCL 50, 264).

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does not compromise the unity of the material common to them. This at least suggests that the

best solution to our puzzle will explain divine personhood in non-specific, non-generic terms.32

Furthermore, Augustine’s approach to the problem has also shifted, for instead of employing

tools of logical and linguistic analysis – tools that have failed to articulate for us the metaphysics

of divine personhood – his approach now is to provide fitting analogies of the divine Trinity,

analogies which can explicate for us how the substantial existence of the three divine persons

does not threaten the simplicity of the essence common to them.

But Augustine quickly makes clear that the examples he has developed in book 7 do not

provide a proper solution to the puzzle at issue. Augustine writes that

neither then in this way do we say that the Trinity is three persons or substances, one

essence and one God, as if these three subsist out of one material, even if whatever that

material is were spread out in these three; for nothing else is of this essence except that

Trinity.33

The success of any analogy of the divine Trinity will be judged relative to how well it can

articulate for us the nature of divine personhood given the unity of the essence of the godhead. A

central problem with both examples provided so far is that the relevant common material is what

the three statues or humans subsist out of, and so that common material is distinct from those

things which it composes. This is not so in the case of the divine Trinity, of which

we speak of three persons of the same being [...]; we do not speak of three persons out of

32 That is, the best solution will not regard the relationship between personhood and being as one of species to

genus, of individual to species, or of two genera both had by some individual. What I think Augustine's analysis bears out is that, regardless of whether ‘person’ is a kind-term, none of the substantial predicates said singularly of the godhead can be regarded as kind-terms. Rather, they are mass-terms, of the same sort as ‘gold’.

33 Aug., trin., VII,6,11 (CCL 50, 264): «Nec sic ergo trinitatem dicimus tres personas uel substantias unam essentiam et unum deum tamquam ex una materia tria quaedam subsistant, etiamsi quidquid illud est in his tribus explicatum sit; non enim aliquid aliud eius essentiae est praeter istam trinitatem».

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the same being, as though what being is were one thing and what person is another, as we

can speak about three statues out of the same gold.34

A proper analogy of the divine Trinity will evidence for us three things which are each wholly

identical to their shared common material; they will not subsist out of that material but rather

will simply be that material. Neither of the analogies Augustine has produced so far evidences

this sort of identity. So our search for an appropriate analogy of the divine Trinity is not

completed with the examples Augustine has so far provided. But that is not to say that Augustine

gives up on his search.35 Rather, in addition to his judgment that both these examples fail as

proper analogies of the divine Trinity, Augustine also provides a diagnosis of why these sorts of

examples were attractive to us as analogies in the first place, and the outline of an intellectual

ascent that will prepare us to continue the search for an analogy that successfully explicates the

nature of the divine Trinity.

To see why both of these examples were attractive to us as analogies of the divine

Trinity, we first need to understand more clearly why they failed. The reason why both examples

failed is that the central objects in each example are corporeal in nature, having spatial dimension

and physical mass. The corporeal nature of the three statues, for example, causes that example to

fail as an analogy of the divine Trinity. First, it fails because each statue could be made of some

34 Aug., trin., VII,6,11 (CCL 50, 264-5): «Tamen tres personas eiusdem essentiae uel tres personas unam essentiam

dicimus; tres autem personas ex eadem essentia non dicimus quasi aliud ibi sit quod essentia est, aliud quod persona sicut tres statuas ex eodem aura possumus dicere»

35 This point seems to me to be largely missed in the literature. The typical interpretation of the text suggests that the second half of book 7 is aporetic, such that the use of ‘person’ is justified merely by the need for Nicene orthodoxy to say something, with lingering logical and metaphysical worries left unresolved. See, e.g., E. Falque, Saint Augustin ou comment Dieu entre en théologie. Lecture critique des Livres V-VII du “De Trinitate”, ‹‹Nouv. Rev. théol.›› 117 (1995), 97-8; G. Madec, “Inquisitione proficiente”, 63; E. Morgan, The Concept of Person in Augustine's De Trinitate, ‹‹Studia Patristica››, 43 (2006), 201-2.

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physical material other than gold, and so ‹‹being gold is one thing, being statues another››.36

Second, it fails because the mass of any given statue will be less than the total mass of the gold

itself, since ‹‹there is more gold in three together than in each one of them, and less gold in one

than two››.37 Augustine thinks this is reflected to some degree in his first example as well. Those

three humans do not exhaust that common nature, since any number of additional individuals can

come to share that same physique, sex and spirit. In the divine case, however, each person is

nothing but the divine essence, and each person is wholly the divine essence, such that the divine

essence is exhausted in the three divine persons. Due to their spatial dimension and physical

mass, then, neither three statues nor three humans can be identical with their common material in

the way that each of the divine persons is identical with the divine essence.

But Augustine thinks it is precisely the corporeality of these examples that makes them so

attractive to us in the first place, which evidences a certain intellectual if not moral failing on our

part. That is the failing of the ‹‹beastly human››, a kind of human who ‹‹can only think of masses

and spaces, little or great, with images of bodies flying around in his mind like phantoms››, and

so is unable to grasp the divine Trinity in any way other than through the sort of examples

considered so far.38 It is no mistake, then, that Augustine concludes book 7 by stating that ‹‹until

one is purified of this sort of uncleanness [i.e. the uncleanness of the beastly human], he must

just believe in the Father and the Son and the Holy Spirit, one God alone, great››.39 To

understand the divine Trinity, and so solve our puzzle about the nature of divine personhood,

36 Aug., trin., VII,6,11 (CCL 50, 265).

37 Aug., trin., VII,6,11 (CCL 50, 265).

38 Aug., trin., VII,6,11 (CCL 50, 265).

39 Aug., trin., VII,6,12 (CCL 50, 265). The mention of God’s greatness is particularly apropos here, given that it is just this characteristic that Augustine will focus on at the beginning of the next book.

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requires a process of intellectual purification, an ascent to a better way of thinking.

Augustine concludes book 7 with a recapitulation of the state of his inquiry thus far. He

admits that an orthodox trinitarian faith needs a term of the kind that ‘person’ is – that is, a non-

relative term which cannot be predicated singularly of the godhead – writing that ‹‹it is now

agreed to use the plural with names besides relatives, on account of the necessity of

argument››.40 And he suggests that we do not yet have a complete understanding of what that

term expresses, acknowledging that ‹‹if this cannot be grasped by the understanding, let it be

held by faith››.41 However, most central for our purposes is the admonition Augustine gives his

readers as they try to understand what the term ‘person’ expresses. When we use such words as

‘person’ in regards to the divine Trinity,

no masses or spatial intervals are to be thought, one [person] is to be thought from

another not by any distance of dissimilarity or of place no matter how little, nor

[is one person to be thought] a little less than another, in whatever way one can be

less than another.42

Augustine’s central concern with spatial size and physical mass here – all necessary aspects of

corporeal bodies, the reason on account of which Augustine’s previous trinitarian examples

failed as suitable analogies of the divine Trinity – is carried over quite explicitly in book 8.

4. Book 8 and the Beginnings of an Intellectual Ascent

After a brief summary of the philosophical conclusions reached thus far in books 5

40 Aug., trin., VII,6,12 (CCL 50, 267).

41 Aug., trin., VII,6,12 (CCL 50, 267).

42 Aug., trin., VII,6,12 (CCL 50, 267): «si iam placet propter disputandi necessitatem etiam exceptis nominibus relatiuis pluralem numerum admittere ut uno nomine respondeatur cum quaeritur quid tria, et dicere tres substantias siue personas, nullae moles aut interualla cogitentur, nulla distantia quantulaecumque dissimilitudinis aut ubi intellegatur aliud alio uel paulo minus quocumque modo minus esse aliud alio potest»

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through 7, book 8 immediately resumes the task of solving the puzzle set out in book 7, and it

introduces that task by returning to the issue of mass. Augustine writes that ‹‹we must put some

limits to repetition, and beseech God as devoutly and earnestly as we can to open our

understandings […] so that our minds may be able to perceive the essence or being of truth

without any mass, without any changeableness››.43 What we must find, then, is a way in which to

think of God as a being without mass. For only in thinking of God in this way will we be able to

understand how a trinity of divine persons does not compromise the simple unity of the godhead

which that trinity is.

Augustine’s mention of mass serves to motivate a discussion about the greatness of God.

The central philosophical issue at the beginning of book 8 is the nature of the greatness of God,

and Augustine’s first task is distinguish for his readers’ between greatness and mass. Echoing

book 7, Augustine writes that

in this Trinity two or three persons are not any greater than one of them alone,

which a person accustomed to the flesh does not grasp, since he grasps nothing

except those created truths which he discerns with the senses as he is able. Yet he

is not able to discover that truth by which they are created.44

The human accustomed to the flesh – that is, the beastly human of book 7 – cannot think of

greatness in terms of anything other than mass, and so he cannot but think that two things will

always be greater than one of them alone, since their collective mass is always greater than that

of each one alone.

43 Aug., trin., VIII,1 (CCL 50, 268).

44 Aug., trin., VIII,1,2 (CCL 50, 269): «Dicimus enim non esse in hac trinitate maius aliquid duas aut tres personas quam unam earum, quod non capit consuetudo carnalis non ob aliud nisi quia uera quae creata sunt sentit ut potest, ueritatem autem ipsam qua creata sunt non potest intueri»

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But Augustine does not simply reiterate in book 8 the diagnosis he offered in book 7. He

also provides a process by which one can rid himself of his flesh-bound intellectual habits.45 The

discussion of God’s greatness actually constitutes the first step in that process; God’s greatness is

introduced precisely as a kind of greatness without mass. Furthermore, Augustine’s use of the

concept of greatness in book 8 is one of four key concepts in that book, the others being truth,

goodness, and love, respectively. Each subsequent concept is introduced in book 8 as identical in

referent – at least in the case of the divine – with the concept previous to it; in fact, God, as

greatness, truth, goodness and love itself, is the measure against which all other instances of

greatness, truth, goodness or love are judged. The introduction of each concept serves as a

further step in the process of intellectual purification.

That book 8 provides for this process of purification seems to me especially explicit in

the transition from the concept of greatness to the concept of truth. For the introduction of the

concept of truth is supposed to aid the reader in distinguishing the concept of greatness from the

concept of mass. In the case of a body, that body’s greatness is its mass, and the mass of that

thing is distinct from the truth of that thing - that is, what that thing is. But for an incorporeal and

unchangeable thing, that thing’s truth will be identical to its greatness. Furthermore, ‹‹where

greatness is simply truth itself, anything that has more greatness will have more truth››.46 In the

case of the persons of the divine Trinity, however, the truth of that Trinity is nothing other than

the truth of each of the persons of that Trinity, since ‹‹the Father and the Son together do not

have being more truly than the Father alone or the Son alone››.47 Augustine draws from this a

45 On De Trinitate, and especially its latter half, as an exercitatio animi, see M. Claes, Exercitatio Animi in

Augusine's De Trinitate, ‹‹Studia Patristica››, 43 (2006), 48.

46 Aug., trin., VIII,1,2 (CCL 50, 269).

47 Aug., trin., VIII,1,2 (CCL 50, 269).

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conclusion about the greatness of the divine Trinity and the persons in it. ‹‹So both [i.e. the

Father and the Son] together are not something greater than each one of them singularly››.48

Since, in the case of the divine, greatness just is truth, the greatness of the Father and the Son

together is nothing other than the greatness of each one of them alone. Consequently, the

greatness of each of the divine persons must be a greatness quite different from that of bodily

things, whose greatness is nothing other than their mass. For, unlike with bodily things, the

Father and Son together will be not greater than each by himself.

By introducing the concept of truth, then, Augustine provides an explanation of divine

greatness by which his readers can understand how the notion of greatness differs from the

notion of mass, and so take an initial step in understanding the nature of divine personhood. It is

no mistake that Augustine sees the introduction of the notion of truth, at least initially, as

liberating. ‹‹Come, see if you can, O soul weighed down with the body that decays and burdened

with many and variable earthly thoughts, come see it if you can – God is truth››.49

Yet this is only an early step in the process of purification. The introduction of truth

proves insufficient because, for a bodily thing, that thing’s truth is not equivalent to its greatness.

‹‹With bodily things it can happen that this gold is as true as that, and yet this [gold] is greater

than that, because in this case to be great is not the same as to be true and it is one thing for it to

be gold, another to be great››.50 Two pieces of gold are both equally true gold, but one piece may

be greater than the other, because it has more mass than the other. As a consequence, if we are

48 Aug., trin., VIII,1,2 (CCL 50, 269).

49 Aug., trin., VIII,2,3 (CCL 50, 271).

50 Aug., trin., VIII,2,3 (CCL 50, 271). That Augustine’s example here is gold seems to clearly allude back to the example of the three statues at the end of book 7, in which all three are composed out of gold yet are able to be of varying greatnesses.

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accustomed to thinking only in terms of bodies and so fail to see that greatness need not be

understood in terms of mass, it seems that we are equally prone to fail to understand that

greatness can be equivalent to truth. Augustine himself recognizes the insufficiency of this step

in the process of purification, writing

do not ask what truth is; for immediately a fog of corporeal images and a cloud of

phantasmata hinders you and disturbs the serenity which delighted you in that

first moment when I said to you “truth.” Come, remain if you can in that first

moment in which so to speak you caught a flash in the corner of your eye when

‘truth’ was said; but you cannot. You fall back into those familiar and earthly

things.51

Thus the introduction of the concept of truth by itself is unable to free us completely from our

flesh-bound habit of thought. It provides only a moment where we catch a sideways glance of

truth itself before we fall back once again into thinking of things in terms of masses and spaces.52

However, the introduction of truth is still a necessary step in that process of purification,

for three reasons. First, the concept of truth is at least the means by which the concept of

goodness can be introduced, and that concept explicitly provides the normative and volitional

grounds for the introduction of the concept of love. It is on account of the concept of love that we

arrive at the first mental trinity of lover, love, and that which is loved. Second, though we see

truth itself only for a moment, we do see truth itself, and so we have an experience of thinking of

51 Aug., trin., VIII,2,3 (CCL 50, 271): «Noli quaerere quid sit ueritas; statim enim se opponent caligines imaginum

corporalium et nubila phantasmatum et perturbabunt serenitatern quae primo ictu diluxit tibi cum dicerem, ueritas. Ecce in ipso primo ictu qua uelut coruscatione perstringeris cum dicitur ueritas mane si potes; sed non potes. Relaberis in ista solita atque terrena»

52 An experience of this sort, and Augustine’s subsequent descent back into more corporeal ways of thinking, plays a crucial role in the Confessiones as well. See Aug., conf., VII,17,23.

22  

something incorporeal.53 As the ending of book 7 makes clear, such an experience is precisely

what we need if we are going to come to understand the nature of divine personhood. Finally,

truth itself more than any other is identified in book 8 as the object of true love, since truth itself

is the standard against which all other things are measured. A human who is believed to be just,

for example, is loved ‹‹according to that form, truth, which the one who is loving perceives and

understands in himself; but this form, truth, is not loved according to a standard derived from

another source››.54 So truth provides for us the means to understand that very truth, which is the

proper object of our love. It provides for the exercise of a cognitive ability of ours and so starts a

process through which we can come to have (as best we can in this life, at least) a proper vision

and love of that very truth, which is nothing other than three divine persons joined in a simple

unity of being.

We find, then, an inquiry into a particular puzzle about the nature of divine personhood

which is inaugurated in book 7 and continues into book 8. The purpose of that inquiry is to

provide an account of the nature of divine personhood, an account coherent with the absolute

simplicity of God. While book 7 sets out that puzzle, and begins an inquiry into its solution, our

attempts are ultimately hindered by a corporeal way of thinking. Book 8 begins to free us from

that way of thinking, and thus prepares us for the trinities that are to follow, trinities of an

incorporeal mind which, as analogies of the divine Trinity, elucidate for us a being who is at

once three persons and one simple essence.

53 In both De Libero Arbitrio and Confessiones, it is the recognition of truth itself which results in the ability to think

of incorporeal things. This ability is precisely what we need in our present inquiry if we are to come to have an understanding of divine personhood; lib. arb., II,xi,30,122-4; II,xii,34,133-4. See also Aug., conf., VII,10,16.

54 Aug., trin., VIII,6,9 (CCL 50, 283).

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5. Lessons about the Investigation into the Human Mind

Once we recognize that book 8 continues a line of inquiry into a puzzle about divine

personhood begun in book 7, I think we can draw from that continuity important lessons about

the larger investigation into mind that begins near the start of book 9 and continues to the end of

the work. One lesson concerns the immediate motivation for that project. What motivates that

investigation is a desire to solve a puzzle about the nature of divine personhood – how each

divine person has his own sort of being without any jeopardy to the simple being of the godhead

itself. This is evidenced by the fact that the philosophical considerations of book 8 do not

conclude with a clear insight into the metaphysics of divine personhood but rather end with an

investigation into love. That investigation produces in book 9 what will be the first in a long

series of mental trinities. It is only when we are presented with a thorough analysis of the mind’s

memory, love and knowledge of itself in book 14 that we can regard that argument as in any way

complete.

Various remarks in book 9 lend support to the claim that Augustine’s thoughts on the

nature of mind are motivated by such a desire. Perhaps the most fundamental criterion of an

adequate analogy of the divine Trinity that develops clearly from Augustine’s investigation into

divine personhood in book 7 is that each member in an analogy of the divine Trinity must be

something substantial, and yet those members collectively must have one essence or substance.

While failing in other respects, the putative analogies of the divine Trinity offered in book 7 met

that criterion, and it is precisely because they met it that they appeared to be analogies of the

divine Trinity in the first place. Throughout book 9, Augustine emphasizes that the mental

trinities he develops also meet that criterion.

At the beginning of book 9, when investigating whether we can understand the divine

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Trinity by looking at the mind’s love of itself, Augustine writes that the mind’s love of itself is

an effective analogy of the divine Trinity in at least this respect: the mind and its love are each

mind, each spirit, and yet they are together one mind and one spirit. ‹‹Insofar as they are spoken

of substantially they are each spirit and they are both together one spirit, they are each mind and

both together one mind››.55 Later in book 9, while admitting that the mind’s knowledge is called

knowledge with reference to another, and so too the mind’s love, Augustine stresses that all three

– the mind, its love, and its knowledge – are each something substantial. ‹‹Love and knowledge

are not in the mind as in a subject, but they too exist substantially, just as mind [exists]; and even

if they are posited relative to each other, still each is its own substance››.56 And yet the mind, its

love and its knowledge are together only one being, and each is equal to that being. «Yet I cannot

see how those three are not of the same being, since the mind is itself loving itself and itself

knowing itself».57 These mental examples are plausible analogies of the divine Trinity precisely

because they meet the criterion set out in book 7 and so explicate for us (to varying degrees of

success) how the divine Trinity can be three persons and yet one simple being. And so it seems

that Augustine’s investigation of mind is motivated by the same concerns which motivate the

analogies developed in book 7.

Given that Augustine’s considerations about the human mind are motivated in this way,

there seems to me to be a second lesson to draw. That lesson is that this investigation of the

human mind constitutes an advance in our search for a solution to the puzzle introduced in book

7, and in particular an advance over the corporeal way of thinking that encouraged examples of

55 Aug., trin., IX,2,2 (CCL 50, 295).

56 Aug., trin., IX,4,5 (CCL 50, 298).

57 Aug., trin., IX,4,7 (CCL 50, 299).

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the sort developed at the end of that book. Just as each subsequent mental trinity developed in

books 9 and 10, and likewise each subsequent mental trinity developed in books 11 through 14,

is to be regarded as an improvement on those that preceded it, so too the turn inward to the

structures of the incorporeal human mind constitutes an improvement over the kind of search for

an analogy of the divine Trinity conducted in book 7. Rather than merely a different sort of

investigation of the divine Trinity than we find in earlier books, the investigation of the mind

constitutes a better sort of inquiry, because it is only through an investigation of the structures of

an incorporeal substance – one's own mind – that we are able to truly understand how there can

be three divine persons, each substantially his own, without jeopardizing divine simplicity.

Augustine himself invites us to view this turn towards the structures of the mind as an

advance in our inquiry in one particular passage. In book 9, Augustine notes that the trinity of the

mind, its love of itself and its knowledge of itself differs in a crucially important way from a

trinity of three golden rings, linked one to the others. Unlike three linked golden rings, the mind,

its love of itself and its knowledge of itself do not subsist out of some common material but

rather are each simply that material. This encourages a comparison to the end book 7 in two

ways. First, the example of the three golden rings with which Augustine contrasts this mental

trinity, while not the same example as any we find in book 7, is similar in all relevant respects. In

particular, it bears a striking resemblance to Augustine’s example of three statues made out of

gold.58 So it seems there is a clear allusion to the sorts of trinities developed near the start of our

inquiry. Second, Augustine employs this example to illustrate again the difference between a

trinity the members of which subsist out of some common material and a trinity the members of

which are each identical to that common material. Just like the examples Augustine developed at

58 In fact, Augustine mentions golden rings in his criticism of this example. See Aug., trin., VII,6,11.

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the end of book 7, the example of three golden rings linked together cannot illustrate for us the

divine Trinity because those three rings only subsist out of gold, and so none are equal to that

gold. Augustine makes this point by writing that ‹‹if they are mixed up together and each strewn

throughout the whole mass, then that trinity will collapse and simply will not be››.59 Since each

ring is not identical with the common material that composes the trinity of which it is a member,

any attempt to make each of those rings identical to that gold destroys the individual being of

each ring. Unlike at the end of book 7, however, Augustine has a trinitarian example of a

different sort with which to contrast that failed analogy. For the mind, its love of itself and its

knowledge of itself do not each subsist of their shared common material, but rather they are

simply that material, with the result that the whole substance of mind is found in each. While not

itself the final mental trinity Augustine will develop, that trinity is representative of the

advantage the investigation of the mind as a whole and the sorts of trinities developed out of that

investigation have over trinities of the sort developed at the end of book 7.60 For each member is

wholly identical with mind, and so wholly within the other two, without any threat to the

individual being of each of those three.

Augustine’s investigation of the human mind is therefore motivated by a puzzle about

divine personhood set out in book 7, and furthermore that investigation serves as an advance in

our inquiry into a solution to it. Like the examples developed at the end of book 7, the mental

trinities developed in books 9 and following are meant to illustrate for us the nature of the divine

59 Aug., trin., IX,4,7 (CCL 50, 300).

60 Note supra that in the example of the mind’s loving itself which Augustine develops at the beginning of book 9, not only are each of the members of that example something substantial, but each is composed of mind and is not composed out of mind. So we can generalize our conclusions here to the (putative) trinity of the mind’s loving itself as well. The same appears to be true about the final mental trinity which Augustine develops in book 10. The mind’s memory of itself, love of itself and understanding of itself are each a substance (though they are called memory, love or understanding relatively), yet all three are not composed out of mind but rather are simply mind, which is a single essence.

27  

Trinity, and thus to explain how it is that a multiplicity of divine persons is compatible with the

simplicity of the divine essence. And unlike the examples developed at the end of book 7, we

find in those mental trinities three substantially unique things which are yet each identical to the

essence common to them all. As such, those mental trinities can illustrate for us (to the extent

possible in this life, at least) how it is that three substantially unique divine persons are each

identical to that whole divine Trinity, a trinity which is nothing other than one simple essence.