Essence and Energies: What Kind of Distinction?

There is much confusion among scholars over the precise nature of the essence-energies distinction. Various authors have identified it as a Thomistic real minor distinction, a Thomistic rational distinction with a foundation in the object, and a Scotistic formal distinction, whereas others deny that any of these descriptions properly apply. The issue is further complicated by the tendency of some of Palamas’ closest followers, such as Philotheos Kokkinos and John Kantakouzenos, to describe the distinction as ‘conceptual’ (κατ’ ἐπίνοιαν), notwithstanding that Palamas himself seems to have avoided describing it in this way. Such varying interpretations point to the need for a careful consideration of the history and meaning of the various types of distinction at play, both Greek patristic and Latin scholastic. After offering such a history, I conclude with some thoughts regarding the ways in which Palamas’ own distinction does, and does not, conform to these various models.

The exact nature of the essence-energies distinction has been controversial ever since the time of Palamas. Within twentieth-century scholarship, this subject was first given prominence by the great Roman Catholic scholar Martin Jugie. Jugie took it as obvious that Palamas meant to distinguish between the divine essence and energies as between two res, or, in other words, that he intended what the scholastics call a real distinction.[1] He was followed on this point by Sébastien Guichardan, who argued specifically that the distinction between essence and energies is a Thomistic real minor distinction.[2] In the subsequent decades, numerous other authors accepted that Palamas intended a ‘real’ distinction.[3] It must be admitted, however, that they often did not define this term or even associate it specifically with the scholastics, so their exact meaning is not always clear.

Other interpreters have identified Palamas’ distinction with the formal distinction of Duns Scotus. This is a view that Jugie and Guichardan argued can be found in some works of Patriarch Gennadios Scholarios.[4] In modern times it was revived by Gérard Philips and has been endorsed by a number of others.[5] Most recently it has been vigorously defended by John Milbank and just as vigorously criticized by Nikolaos Loudovikos.[6] Mark Spencer also takes this view in part, although he limits its scope to those energies that are ‘absolute attributes’ as opposed to those that are contingent acts.[7]

Another important recent development has been renewed attention to Palamas’ followers during the last century of Byzantium, both as figures important in their own right and for the light they shed on Palamas’ thought. Jugie offered a preliminary history of the Palamite controversy in which he alleged that the prevalent trend among these figures was to back away from Palamas’ real distinction.[8] In recent years the editing and publication of new texts has prompted renewed inquiry. The most thorough contribution to date is undoubtedly that of John Demetracopoulos.[9] Like Guichardan, Demetracopoulos sees Palamas as advocating a real minor distinction. He further sees the description of the distinction as ‘conceptual’ (κατ’ ἐπίνοιαν) by Palamas’ earliest followers, such as the Patriarch Philotheos Kokkinos, as fundamentally a way of restating this understanding.[10]

Demetracopoulos draws a sharp line between these followers and those influenced by Byzantine Thomism, beginning with the former emperor, John VI Kantakouzenos, in his correspondence with Paul, the Latin Patriarch of Constantinople. According to Demetracopoulos, Kantakouzenos and his successors reinterpreted the distinction kat’ epinoian (a phrase that they, like Kokkinos, use to describe the essence-energies distinction) as a rational distinction with a foundation in the object (cum fundamento in re), thereby bringing their own form of Palamism into line with Thomism.[11] Antoine Lévy, who has also written on this issue, agrees regarding Kantakouzenos but draws no line between him and Palamas or his early followers, seeing a rational distinction cum fundamento in re as the consistent teaching of the entire Palamite school.[12] Nikolaos Loudovikos too would seem to be roughly of this view; he understands kat’ epinoian as meaning ‘made by mind’, and takes Palamas and his followers to assert a distinction that is in no way ‘ontological’ but merely mental, like that between the existence and attitude of a personal subject.[13] Presumably, in referring to the distinction as ‘made by mind’ he has in mind something like the scholastic rational distinction.

Finally, yet another contingent denies that the scholastic distinctions are of any use at all in understanding Palamas, whose thought it sees as sui generis.[14] The wide disagreement we have noted arguably lends some support to this conclusion. On the other hand, in itself it is merely a negative statement, and does nothing to clarify the nature of Palamas’ thought or to relate it in an illuminating way to other forms of theology.

In view of this widespread disagreement, I believe it may be of some use to step back and ask about the purpose and value of the various distinctions that are at play. Both the distinction kat’ epinoian and the various scholastic distinctions have a history, and it is only in light of that history that their application (or lack thereof) to the essence-energies distinction can be properly assessed. I will therefore spend the greater part of this essay recounting their development and the range of their traditional applications. Having done so I will then turn to Palamas to ask what light, if any, they shed on his thought.

Epinoia: Early Stages

The history of epinoia prior to the Cappadocians has been addressed adequately by others and need not be repeated here.[15] Broadly speaking, epinoia includes the faculty, the act, and the resulting conception formed by the process of reflecting upon and analyzing the deliverances of sense perception. Since this process can include taking things perceived and recombining them so as to produce fictions, such as giants and goat-stags, some of its products are merely imaginary. More interestingly for our purposes, its deliverances also include different ways of conceptualizing or describing a given object. The Stoic Posidonius, for example, says that substance (οὐσία) and matter (ὓλη) are the same in reality (κατὰ τὴν ὐπόστασιν) and differ solely in epinoia.[16] By this he apparently means that the same thing is called substance in that it exists, and matter in that it is subject to change.

Such an analysis was occasionally applied to theological matters, although not in any sustained way. Philo of Alexandria says that kyrios and despotēs are two names of the divine Ruling Power which are the same in their substratum (ὑποκείμενον), but differ kat’ epinoian insofar as they have different meanings.[17] Plotinus says that Intellect is ‘all one nature divided into parts [i.e., genera] by our conceptions (ἐπινοίαις)’.[18] This latter statement requires some clarification. Despite his reference to ‘our conceptions’, Plotinus goes on to argue that the ‘parts’ of Intellect thus distinguished—being, rest, motion, sameness, and difference—are intrinsic to reality as such.[19] This is what one would expect, given that these ‘parts’ are in fact the five ‘greatest kinds’ of Plato’s Sophist. Evidently, then, epinoia here is a matter of discovery rather than invention.[20]

Within early Christian literature, the most prominent reference to epinoia was undoubtedly Origen’s treatment of the different titles of Christ as epinoiai. He includes in this group not only those that are clearly relational (such as ‘light of men’, ‘shepherd’, and so on) but also those that presumably pertain to Christ in his eternal being, such as ‘wisdom’, ‘word’, ‘life’, and ‘truth’.[21]

Another significant early discussion occurs in Origen’s great critic, Methodius of Olympus. In the course of critiquing Origen’s view of the resurrection, Methodius distinguishes three ways in which things can be separated: in thought (ἐπινοίᾳ), in actuality (ἐνεργείᾳ) but not subsistence (ὐποστάσει), and in both actuality and subsistence. An example of separation in thought is that of matter from its qualities; of that in actuality but not subsistence, when a statue is melted down and its shape is separated so that the shape no longer exists; of that in actuality and subsistence, when two things that had been mingled (such as wheat and barley) are physically drawn apart.[22] This is a more developed version of the commonplace Stoic distinction between difference kat’ epinoian and kata tēn hypostasin which we have already observed in Posidonius.[23]

As is well known, epinoia first became a topic of discussion in its own right during the Eunomian debate. St Basil initially describes epinoia in a way that emphasizes the role of the mind in dividing what otherwise appears simple: ‘whatever seems simple and singular upon a general survey by the mind, but which appears complex and plural upon detailed scrutiny and thereby is divided by the mind—this sort of thing is said to be divided in thought (ἐπινοίᾳ) alone’.[24] Although he notes that imaginary constructions are said to be produced by epinoia, plainly his focus is on its role in discerning that which is in some sense truly present in the object. Besides imaginary objects, his other examples are the analysis of a body into its constituent qualities—color, shape, solidity, size, and so on—and the many ways of naming grain such as ‘fruit’, ‘seed’, and ‘nourishment’. Both, he says, are the result of ‘more subtle and precise reflection’ upon a concept that first arises from sense perception.[25] The subsequent chapter goes on to apply the same analysis to terms used of Christ and of God. The different names Christ applies to himself, such as ‘door’, ‘vine’, and ‘light’, are given in accordance with different epinoiai based upon his different activities and relations to creatures. Terms used of God, such as ‘unbegotten’ and ‘incorruptible’, are likewise formed by considering through epinoia different aspects of the divine life.[26]

As the Against Eunomius proceeds, the linkage between epinoia and activity (ἐνέργεια) becomes stronger. Basil sees Eunomius’ refusal to ‘consider anything at all [about God] by way of conceptualization (κατ’ ἐπίνοιαν)’ as leading to the absurd conclusion that all attributes of God refer to the divine substance. He observes that it is absurd to suppose that God’s creative power, providence, and foreknowledge are His substance, summarizing the point by asking, ‘is it not ridiculous to regard every activity (ἐνέργειαν) of His as His substance?’[27] Evidently, just as in the case of Christ, the different names formed by epinoia are based upon different activities and relations to creatures. As Basil adds later, ‘we are led up from the activities of God (τῶν ἐνεργειῶν τοῦ Θεοῦ)… and so come in this way to an understanding of His goodness and wisdom’.[28]

Two further passages of Basil were particularly significant for later developments. In the course of criticizing Eunomius’ view that ‘the Father is greater than I’ (John 14:28) implies a temporal priority, Basil observes that there is a natural order between cause and effect even when they are simultaneous. He cites the case of fire and its light, observing that ‘we do not separate these things from one another by an interval, but through reasoning (τῷ λογισμῷ) we consider as prior the cause to the effect’, and that the same is true in the case of the Father and the Son.[29] Despite the absence of the term epinoia, it is clear that the seed is here planted for seeing the distinction between the Persons of the Trinity as kat’ epinoian. If we recall that Basil elsewhere emphasizes the lack of any interval (διάστημα) between the divine Persons, whereas human persons are separated by place and external circumstances, it is not hard to see how this line of thought might be carried further to see the unity of the Trinity as real (πράγματι), whereas that of created persons is kat’ epinoian.[30]

The second passage occurs in Against Eunomius IV, a work commonly attributed today to Didymus the Blind or Apollinaris but accepted by the Byzantines as by Basil.[31] The author argues that the notoriously problematic verse, ‘the Lord created me the beginning of his works’ (Prov. 8:22), refers to ‘the form of a servant’ taken on by the Word, whereas the parallel statement a few verses later, ‘before all the hills he begets me’ (8:25), refers to the Word in his divinity. He explains, ‘in all this we do not speak of two, God alone and a man alone (for they are one), but we consider the nature of each conceptually (κατ’ ἐπίνοιαν)’.[32] He thus offers what was to become an important precedent for applying the distinction kat’ epinoian to the two natures of Christ.

Although Basil’s colleague, Gregory Nazianzen, did not deal at length with epinoia, it is worth noting that he, too, sees the distinction between Christ’s natures as conceptual. In the fourth Theological Oration he argues that the terms used by Christ to address the Father differ with respect to Christ’s two natures, ‘God’ being a term Christ uses in his human nature and ‘Father’ in his nature as God the Word. He then adds: ‘An indication of this is that whenever the two natures are separated in conception (ταῖς ἐπινοίαις) from one another, the names are also distinguished; as you hear in Paul’s words, ‘‘The God of our Lord Jesus Christ, the Father of glory’’’.[33] Like the similar statement in Pseudo-Basil, this passage would have an important influence on subsequent debates.

Gregory also goes further than does Basil in emphasizing the real unity of the Trinity in contrast to the merely conceptual unity of the human race. In the Trinity, he says, there is one essence, one nature, and one appellation (κλῆσις), although we assign distinct names in accordance with our various conceptions (ἐπινοίαις).[34] By contrast, the unity of human nature is perceived only in thought (ἐπινοίᾳ), whereas human individuals are separated from one another in time, dispositions, and power.[35]

It was left to Basil’s younger brother, Gregory of Nyssa, to return the focus directly to epinoia in his own Contra Eunomium.[36] We will note here only a few highlights from his lengthy discussion.[37] Gregory develops more fully than does Basil the subtle interplay between human mental processes and the objective reality under consideration. In opposition to Eunomius, who had held that ‘unbegotten’ uniquely and adequately describes the divine essence, Gregory holds that terms applied to God are human creations expressive of human epinoia. Such terms aim only to give a ‘clear and simple declaration of our mental processes (τοῖς τῆς διανοίας κινήμασιν) by means of words attached to, and expressive of, our ideas (νοήμασι)’.[38] On the other hand, epinoia is answerable to reality, and when functioning properly it merely discovers or reveals that which is already there. Gregory defines epinoia as ‘the method by which we discover things that are unknown, going on to further discoveries by means of what adjoins to and follows from our first perception with regard to the thing studied’.[39] He recognizes that ‘it is possible for this faculty to give a plausible shape to what is false and unreal’, but adds that epinoia ‘is nonetheless competent to investigate what actually and in very truth subsists’.[40] In other words, our mental processes, when functioning properly, are not merely ours, but answer to and reveal the actual structure of reality.

More precisely, Gregory, like Basil, holds that the concepts formed by epinoia correspond directly to divine activities or operations (ἐνέργειαι). Gregory is more explicit than his brother in holding that terms said of God actually name the energeiai. They are thereby ‘shadows of the things themselves’, that is, of the acting agent. He explains:

Are we not clearly taught… that the words which are framed to represent the movements of things are shadows of the things themselves? We are taught that this is so by holy Scripture through the mouth of the great David, when, as by certain peculiar and appropriate names derived from the operation (ἐνεργείας) of God, he thus speaks of the divine nature: ‘The Lord is full of compassion and mercy, long-suffering, and of great goodness’ (Ps. 103:8). Now what do these words tell us? Do they indicate his operation or his nature? No one will say that they indicate (ἔχειν τὴν σημασίαν) anything other than his operation.[41]

Among the names formed from the divine energeia is the term ‘God’ (Θεός) itself, which has ‘come into usage from the activity of His oversight, for our faith tells us that the deity is everywhere and sees (θεᾶσθαι) all things’.[42] In general, Gregory says, the many different forms of beneficent divine energeia ‘pass over into the form of a name, and such a name is said by us to be arrived at by conception (ἐπινοίᾳ)’.[43]

We may also briefly note a passage in which Gregory applies the distinction kat’ epinoian to Trinitarian theology. Speaking of the co-eternity of the Holy Spirit with the Son and the Father, he says that the Spirit ‘is in touch with the Only-begotten, who in conception alone (ἐπινοίᾳ μόνῃ) is conceived of as before the Person of the Spirit in accordance with the account of the cause’.[44] Here ‘in conception alone’ is a way of emphasizing that the priority of the Son to the Spirit is solely causal, rather than temporal. As we shall see below, the precise meaning of this phrase became a point of contention during the filioque controversy.

Even in this passage, epinoia is clearly more than a mere act of human naming; and elsewhere Gregory’s account of it is emphatically realist. The realism of the Cappadocians seems to have emboldened later authors to apply this concept even more broadly.

Epinoia and the ‘Real’ Distinction

For the sake of brevity we shall note only one fifth-century author, Cyril of Alexandria. Cyril builds upon the suggestion of Basil and Gregory Nazianzen that the distinction among the Persons of the Trinity is recognized through reasoning to affirm explicitly that it is kat’ epinoian. Interpreting the statement of Christ that ‘I am in the Father, and the Father in me’ (John 14:11), he offers as an analogy how sweetness might say the same of honey, or heat of fire. In each case the two are divisible in epinoia, but one in nature and substance.[45] Just as had Basil, Cyril makes it clear that calling the distinction conceptual does not deny that it exists within the natural order. On the contrary, the distinction is precisely that between a cause and the effect that comes forth from it by a partless and indivisible procession (πρόοδος).[46]

In the period after Chalcedon the primary application of the distinction kat’ epinoian naturally shifted to Christology. A number of authors followed up on the suggestion of Gregory Nazianzen and Pseudo-Basil that the distinction between Christ’s divine and human natures is kat’ epinoian. It is in this context that we begin to find the contrast between a distinction that is conceptual and one that is ‘real’. Leontius of Byzantium affirms that the humanity and divinity of Christ are separated in epinoia but not in actuality (ἐνεργείᾳ).[47] Eustathius Monachus does the same, offering ‘in reality’ (πραγματικῶς) as a synonym: ‘we do not divide the natures in actuality, or, as one might say, in reality, but they are distinguished conceptually’.[48] Theodore of Raithu contrasts the two natures of Christ, which are ‘united in actuality and in reality, and distinguished solely in epinoia’, with created hypostases, which are ‘united solely in epinoia, and distinguished from one another in actuality and reality’.[49] In a particularly interesting passage, the Emperor Justinian draws a parallel between the distinction of soul and body in thought alone (μόνῳ λόγῳ καὶ θεωρίᾳ) and the similar distinction between the two natures of Christ, which nonetheless are not divided in reality (πραγματικῶς).[50] Although he does not mention epinoia, the implication would seem to be that the distinction of soul and body is kat’ epinoian.

From the contrast of the distinction kat’ epinoian and that which is ‘real’, it is a short step to distinguishing two kinds of existence, the merely conceptual and the actual. However, the two contrasts do not map neatly onto one another, for items that are distinguished kat’ epinoian can both exist in actuality. This is in fact essential to neo-Chalcedonian Christology. Thus, Leontius of Byzantium, immediately after affirming that the humanity and divinity of Christ are separated in epinoia, adds that they nonetheless exist in actuality.[51] Pamphilius Theologicus makes a similar observation.[52] Leontius of Jerusalem observes (by way of reductio) that if Christ’s human nature existed only in thought (ἐπινοίᾳ), he could possess that nature only in thought and not in reality (πράγματι).[53]

The appearance of these two contrasts—one a distinction between ways of thinking or considering something, the other between types of reality—among a variety of authors in the sixth century naturally gives rise to the question of philosophical influence. It is well known that Christian theology of this era was permeated by the influence of the Aristotelian commentaries of Ammonios, son of Hermeias, who lectured in Alexandria from around 480 to the 520s, and his students and successors.[54] Although the Christian tradition already contained internal developments that would have led in the directions we have noted, it seems likely that there was also some influence from the Aristotelian commentary tradition. Already in the Metaphysics, Aristotle had noted that truth and falsity are not in things (πράγματα) but in thought (διανοίᾳ), since they arise from mental operations of combination and division.[55] He also frequently observes that two things may be separable in definition (λόγῳ) but not spatially or in their being (τὸ εἶναι), such as the same surface viewed as convex and concave, or the road from Athens to Thebes and from Thebes to Athens, or a given act of learning and the corresponding act of teaching.[56] Although Aristotle himself does not use the term epinoia in this connection, it is not hard to see how his commentators might find in such passages a precedent for distinguishing existence which is in epinoia from that which is real. This development was no doubt furthered by the Stoic distinction between existence kat’ epinoian and kath’ hypostasin, as well as by Porphyry, who in his Isagoge famously poses the question of whether genera and species subsist or lie in simple conceptions alone (μόναις ψιλαῖς ἐπινοίαις).[57]

Following up on these hints, the commentators developed a technical doctrine of the distinction kat’ epinoian roughly concurrent to that of the sixth-century authors we have noted. Like their contemporaries among the theologians, they shifted readily (and sometimes almost imperceptibly) between epinoia as a mental operation and as a mode of existence. Existence in ‘bare’ epinoia or epinoia alone was identified with existence that is entirely a product of human thought, such as that of the goat-stag.[58] By contrast, epinoia that is without qualification (i.e., not bare) is that by which we separate things that are otherwise inseparable, such as the potency and actuality of the sun, or a physical triangle and its shape, or body (in general) and color.[59] Some accidents can be separated from their substratum both in epinoia and actually, like the white of a white man, whereas others can be separated only in epinoia, like the black of an Ethiopian.[60] Yet even epinoia cannot remove essential qualities, such as the changelessness and eternity of the gods, or make things that are properly opposites, like rationality and irrationality, be present together.[61]

A particularly interesting application of these distinctions is to the realm of mathematics. The question of whether geometrical entities exist solely kat’ epinoian or also kath’ hypostasin had already been posed by Posidonius, who affirmed both.[62] Within the Aristotelian tradition it was more commonly held that they exist kat’ epinoian alone.[63] On this view, entities such as the triangle or square are enmattered in their hypostasis but immaterial in epinoia; as Pseudo-Elias remarks, geometry contemplates its objects solely τῷ νῷ καὶ τῇ ἐπινοίᾳ.[64] They are thus intermediate between sensible objects, which are enmattered in both hypostasis and epinoia, and divine things, which are immaterial in both respects. This treatment of mathematical entities is strikingly parallel to that of the two natures of Christ among the theologians, and it seems likely that the long tradition of debate on this subject among the philosophers helped shape their terminology.

Returning now to the theologians, the seventh and eighth centuries saw a further consolidation of the various applications of the distinction kat’ epinoian already mentioned. Maximus the Confessor, in the course of arguing against the Origenist belief in the pre-existence of the soul, affirms that soul and body are distinguished only in epinoia.[65] As he goes on to explain, this does not exclude that the soul survives the death of the body or that each of them has its own essential principles (λόγοι κατ’οὐσίαν). The point is rather that they remain essentially and intrinsically related, so that each of them ‘possesses as its own form the whole human being’ of which it had been a part.[66] Maximus also applies the distinction kat’ epinoian freely elsewhere, including in cases where the two items so distinguished cannot exist separately; for example, he explains that the birth by ‘vital inbreathing’ spoken of by Gregory Nazianzen is only conceptually distinct from birth through normal bodily processes.[67]

The example of soul and body figures importantly in the Dialectica of John Damascene, where it is enlisted to clarify the difference between a veridical and a merely imaginative use of epinoia. Like the commentators, John identifies the latter with ‘bare’ epinoia. Epinoia in the fuller sense is ‘a certain thinking out and consideration by which the general concept and unanalyzed knowledge of things are unfolded and made fully clear… Man, for example, appears to be simple, but by epinoia he is discovered to be twofold—made up of a body and a soul’.[68] The phrasing of this definition largely follows Leontius of Byzantium, although the example of body and soul is probably drawn from Maximus.[69] The durability of the definition in the scholastic literature may be indicated by the fact that, five centuries later, Nikephoros Blemmydes in his Epitome of Logic (1237) gives an almost identical account of the two kinds of epinoia—one, the faculty by which things that exist together by nature are distinguished, and the other, ‘bare’ epinoia which considers as real things that are not.[70]

Nonetheless, the actual application of epinoia in theology was more complex. In On the Orthodox Faith John elaborates upon the role of epinoia in the more robust sense. Much like Theodore of Raithu, he observes that created hypostases of the same species are divided in reality (πράγματι) but united by reason and epinoia. (This does not mean that their reality is merely a mental construct; John is a moderate realist about universals, so the unity of the members of a species is discovered, not created, by the mind.)[71] In the case of the Trinity, the opposite is the case: the divine Persons are united in reality, owing to their unity of essence, energy, will, and judgment, but distinguished by epinoia because of the distinctive property (ἰδιότης) and mode of subsistence of each.[72] Obviously, to be distinguished by epinoia is here fully compatible with each Person being distinct from the others in a way that is mind-independent.[73]

The same is true later in the same work, when John invokes the conceptual distinction while cataloging the various kinds of statement made of Christ in Scripture. The flesh of Christ and the Word, he says, although ‘really inseparable’, can be distinguished by ‘tenuous thoughts or subtle imaginings’ (ἰσχναῖς ἐπινοίαις ἤτοι νοῦ λεπταῖς φαντασίαις), and this is what is done when Scripture refers to Christ as servile and ignorant, as his flesh would be apart from its union with the Word.[74] Plainly, although the flesh of Christ and the Word are inseparable, the distinction between them is not merely introduced by our thought, but is a recognition of that which exists in nature. A further such example is Christ’s referring to the Father as ‘my God’, where Christ himself engages in an act of epinoia. John refers to this as a case of ‘mere (ψιλίν)’ conceptual distinction.[75] Evidently the qualifier ‘mere’ here does not indicate a purely imaginary construction, as in other authors we have examined; instead it emphasizes that Christ’s statement, although not false (since as man he can truly say that the Father is his God), must be understood as a voluntary condescension undertaken for our sake.

These statements by the Damascene later became the standard by which right and wrong ways of thinking of Christ’s humanity are to be judged. In the Synodikon of Orthodoxy we find several passages condemning those who misuse the distinction kat’ epinoian in a way that wrongly separates Christ’s humanity from his divinity.[76] The first derives from a synod summoned in 1117 against Eustratios of Nicaea. Although Eustratios renounced the condemned views, a statement was nonetheless included in the Synodikon anathematizing those who ‘do not employ with all reverence the distinction kat’ epinoian for the purpose of showing only the difference between the ineffably conjoined two natures in Christ… but employ this distinction improperly and say the humanity which Christ assumed is different not only in nature but in dignity, and that it worships God and offers a servile ministry’.[77] Although the two natures can be distinguished kat’ epinoian, then, such a distinction must not be used to envision the human nature as capable of acting independently or to conjecture what it would be like if it were to exist alone.

In 1170 further condemnations were added pertaining to the correct interpretation of the statement of Christ that ‘the Father is greater than I’ (John 14:28). The first and most detailed one condemns those who

say that the Lord’s words are only understandable when the flesh is considered purely conceptually (κατὰ ψιλὴν ἐπίνοιαν) in separation from the divinity as though it had never been united, and who do not receive this saying of a pure conceptual division in the sense in which it was uttered by the holy Fathers—who employ it only whenever servitude and ignorance are mentioned, since they could not endure that Christ’s flesh, which is one with God and of the same honor, be insulted by such terms—but say instead that the natural properties, which truly belong to the Lord’s flesh that is enhypostatic with his divinity and remains indivisible from it, are to be understood purely conceptually, and thus they dogmatize the same concerning things unsubstantial and false as they do for the substantial and true.[78]

Here again there is a warning that the distinction kat’ epinoian between the two natures does not license one to envision the human nature existing on its own. A further anathema on the same subject aimed at Constantine of Corfu mentions specifically his divergence in this regard from the teaching of John of Damascus.[79] A yet further condemnation (added later the same year) condemns the similar teaching of John Eirenikos.[80] In addition, a clause was added to the profession of faith required of candidate bishops before their ordination, affirming that Christ’s human nature ‘is in no way to be considered naked and separated from the divinity by a subtle conceptual (κατ’ ἐπίνοιαν) division, but is always to be seen subsisting with the Logos in a single hypostasis’.[81]

Another significant episode showing some uneasiness over the distinction kat’ epinoian occurred in the conflict between Stephen of Nicomedia, a theological adviser to the Patriarch of Constantinople, and St Symeon the New Theologian. According to the Life of Symeon by Niketas Stethatos, at their first meeting (circa 1003), Stephen posed to Symeon the question, ‘how do you distinguish (χωρίζεις) the Son from the Father, in concept or in reality?’[82] I translate χωρίζεις here as ‘distinguish’ because that is undoubtedly the meaning intended by Stephen; like earlier authors, he uses χωρίζειν as at least potentially indicating no more than a mental operation.[83] Symeon, however, chose to take the term in a quite different way. His reply (included among his works as Hymn 21) assumes that by χωρίζεις Stephen means ‘separate’. Symeon accordingly affirms emphatically that the Father and Son can be separated neither in concept nor in reality, and that any suggestion they can be is heretical.[84] Symeon does not address whether they can be distinguished conceptually, a view that had been orthodox since the time of the Cappadocians. Since he clearly intends by χωρίζεις something more radical than distinction, the only real novelty in his view is terminological rather than substantive. Nonetheless the difference between separation and distinction is sufficiently subtle that the net effect of his discussion was probably to cast some doubt on the very notion of a conceptual distinction, at least as regards the Trinity.

The controversy over the filioque brought the question of conceptual distinction in the Trinity to renewed attention. The so-called Synodikon against John Bekkos, issued (at least in its current form) in 1285, includes a condemnation against those who attempted to draw support for the filioque from the statement of Gregory of Nyssa mentioned earlier that the Son is prior kat’ epinoian to the Spirit.[85] The document explains that ‘the Son is regarded as prior kat’ epinoian on account of the nomenclature of the relationships which lead to divine knowledge of the Person of the Spirit’.[86] In other words, the role of the conceptual distinction here is purely epistemic and does not (contrary, perhaps, to the prima facie meaning of the text) indicate a priority in the causal order. Here again we see some caution regarding the application of the distinction kat’ epinoian to the Trinity, owing in this case to its potential exploitation on behalf of an unwanted conclusion.

Nonetheless, as Demetracopoulos has noted, in the fourteenth century it remained commonplace to refer to the Persons of the Trinity as distinguished conceptually.[87] So we find something of a mixed scorecard: continuing use of the terminology of epinoia, but, in at least some quarters, confusion or hesitation regarding its meaning.

Distinctions in Aquinas

Let us turn now to the West. Aquinas’ treatment of the various kinds of distinction would seem to have three major roots. One is the tradition of Aristotelian exegesis stemming from Boethius, who translated and commented on several works of the Organon as well as Porphyry’s Isagoge. His second Isagoge commentary includes a well-known passage in which he applies the Aristotelian understanding of the formation of mathematical entities to the problem of universals. According to Boethius (explicating, he says, the view of Aristotle), just as the mind ‘by its own power and thought (cogitatione)’ can understand separately geometrical entities which subsist only in bodies, so it can do the same for species and genera. Naturally this raises the question of how the same thing (species and genera) can subsist as particular in sensible objects while being understood as universal in the intellect. Boethius explains:

For there is nothing to prevent two things which are in the same subject from being different in reason (ratione diversae), like a concave and a convex line, which although they are defined by diverse definitions and although the understanding of them is diverse, are nevertheless always found in the same subject.[88]

In effect Boethius here extrapolates what in Aristotle had been a contrast between two qualities (concave and convex) existing at the same ontological level, to the quite different question of how the same entity can exist at two different levels, particular and universal. Although this brief remark (which Boethius does not amplify further) is not yet a systematic contrast between a ‘real’ and rational distinction, plainly it is a first step in that direction.[89]

A second (and undoubtedly more significant) influence was Latin Trinitarian theology. Let us note first the introduction into this arena of the distinction kat’ epinoian by Burgundio’s Latin translation of On the Orthodox Faith (1153–54). The crucial passage in chapter 8 reads as follows:

One should know that it is one thing actually (πράγματι, re) to observe something and another to see it through reason and thought (λόγῳ καὶ ἐπινοίᾳ, ratione et cogitatione). Thus in all creatures there is an actual distinction (διαίρεσις πράγματι, divisio re) to be seen between the individual substances. Peter is seen to be actually distinct from Paul. But, that which is held in common, the connection, and the unity is seen by reason and thought… The aforesaid is true of all creation, but it is quite the contrary in the case of the holy, supersubstantial, all-transcendent, and incomprehensible Trinity. For here, that which is common and one is considered in actuality (πράγματι, re) by reason of the co-eternity and identity of substance, operation, and will… And the oneness of each is not less with the others than it is with itself, that is to say, the Father and the Son and the Holy Ghost are one in all things except the being unbegotten, the being begotten, and the procession. It is by thought (ἐπινοίᾳ, cogitatione) that the distinction is perceived.[90]

Burgundio’s choice of cogitatio to translate epinoia was certainly reasonable. However, whereas the Damascene’s original readers were already familiar with the meaning of epinoia in patristic usage, his Latin readers were not.[91] Appearing thus abruptly, the notion that the distinction among the Persons of the Trinity is merely in thought (cogitatione) and not reality (re) no doubt appeared jarring. As we shall see in a moment, it was gently but firmly rejected by Aquinas.

The translation of John Damascene was followed in short order by the Sentences of Peter Lombard (1155–57). Although Peter knew of the Damascene’s work, he makes no mention of a distinction cogitatione among the Persons. He is content to affirm that there is a distinction between them, as well as among their personal attributes, without attempting to specify its nature.[92] Of more moment was his teaching that the divine essence is ‘one certain highest thing’ (una et summa quaedam res).[93] The three Persons, he adds, are also three things (res).[94] This naturally raises the question of the relationship between the one res which is the essence and the three res which are the Persons. The Lombard’s answer is to affirm that there is a ‘distinction in the mode of understanding (distinctionem secundum intelligentiae rationem) when we say hypostasis and when we say essence, since the latter signifies what is common to the Three, and the former does not’.[95] Although he says no more about the nature of this distinction, the immense influence of the Sentences ensured that the positing of some form of mental distinction between essence and person would thereafter figure prominently in scholastic theology.

The Lombard’s teaching was attacked by Joachim of Fiore, who objected that describing the divine essence as a res in effect posits a fourth reality in God.[96] The Fourth Lateran Council in response decisively affirmed the Lombard’s view, including the assertion that the divine essence is a certain highest res. In order to deny the inference that there are four realities in God, it further specified that this res is identical to each of the Persons.[97] The council did not, however, clarify in precisely what way (if at all) person and essence are distinct.

The third important influence was the wide dissemination (and adoption into the curriculum at the University of Paris) during the 1240s of Latin translations of Aristotle’s non-logical works. As noted earlier, Aristotle observes that two things, such as the road from Athens to Thebes and from Thebes to Athens, may be separable in definition (λόγῳ) but not spatially or numerically. In Latin such things are said to differ ratione or secundum rationem, but to be the same secundum rem.[98] It is not surprising that theologians turned to this Aristotelian technical terminology—already adumbrated by Boethius—to provide a way to speak more precisely regarding distinctions in the Trinity.

We shall bypass the earliest such attempts, such as those of Albertus Magnus and Bonaventure, in order to focus on Aquinas.[99] Much like Peter Lombard and the Fourth Lateran Council, but now using Aristotelian terminology, Aquinas holds that each of the Persons differs from the divine essence not in reality (re) but only rationally (secundum rationem or ratione).[100] By contrast, the Persons differ from one another by a distinctio realis.[101] Such a distinction must be grounded on some essential or intrinsic difference.[102] In creatures this must be some difference of matter or form, such as that between objects that differ in number, species, or genus.[103] In God there is no matter, of course, and only a single form, the divine essence. Nonetheless a real distinction can be present because there is relative opposition such as that of ‘begetting’ and ‘being begotten’. In general, in immaterial entities it is necessary and sufficient for a real distinction that there be some opposition of negation and affirmation, or at least, some form of relative opposition.[104]

In the course of defending his belief in a real distinction among the Persons, Aquinas considers and rejects—by gently reinterpreting—the teaching of John Damascene that they differ ratione et cogitatione. In his Commentary on the Sentences this text appears among the objections to Aquinas’ own view, and the main body of the article notes that to say that the Persons are distinguished by reason alone ‘sounds like the Sabellian heresy’.[105] Aquinas accordingly asserts that the Damascene did not really mean what he says: ‘“by reason” (ratione) means “by relation” (relatione), and relation is called ratio with reference to the essence, as was said in the main answer’.[106] This comment ignores the amplifying term cogitatione, which makes the Damascene’s meaning clear beyond any doubt. Already we see here how the Greek and Latin distinctions lend themselves to mutual misunderstanding, for whereas it is perfectly orthodox to say in Greek that the distinction among the Persons is kat’ epinoian, to say that it is cogitatione sounds to Latin ears like Sabellianism.

For our purposes, the most important application of this classification of distinctions is to the divine attributes. Aquinas holds that ‘absolute properties’ in God such as goodness and wisdom are not opposed to one another and so are not really distinguished, whereas such properties are really distinguished when they exist in creatures.[107] The distinction among the divine attributes is instead merely rational. To say this alone, however, is not particularly illuminating, for there are different kinds of rational distinction. Aquinas’ fullest discussion of this topic is in his Commentary on the Sentences:

A multiplicity of names can occur in two ways. (1) One is from the part of the intellect because, since names express the understanding, one and the same thing can be signified by diverse names according as it can be diversely accepted by the intellect… This can occur in two ways. One is (a) in accordance with negations by which the conditions of creatures are removed from God so that negative names are produced. Such names are multiplied by the conditions of creatures that are negated of God, especially those which universally accompany every creature, such as ‘immeasurable’, ‘uncreated’, and so on. The other is (b) in accordance with the relation of God to a creature which is nevertheless not really in God, but in the creature. In this way those divine names which convey some disposition toward a creature are produced, such as ‘Lord’, ‘King’, and others of this sort. (2) Likewise a multiplicity of names can occur from the part of a thing according as names signify the thing. It is in this way that names are produced expressing that which is in God. In God, however, there is not to be found any real distinction except that of the Persons which are three things, and from thence comes the multiplicity of personal names signifying the three things. But besides this, there is also to be found in God a distinction of intelligible characters (rationum), and these really and truly are in Him, such as the intelligible characters of wisdom and goodness, and others of this sort. All of these are indeed really (re) one, and differ rationally (ratione). They are preserved in property and truth insofar as we say that God is truly wise and good, and not only in the intellect of the one reasoning. Thence are produced the diverse names of the attributes. Although they all signify one thing, they nonetheless do not signify it according to one intelligible character (rationem), and therefore are not synonyms.[108]

It is notable that Aquinas here insists that, although the various divine attributes are one in reality (re), nonetheless their intelligible characters (rationes) ‘really and truly are in Him’. In this respect the multiplicity of attributes differs from that of negative and relational terms said of God, which is produced solely by the intellect. Aquinas goes on to add that it is precisely because their rationes differ in God, that attributes such as wisdom and goodness differ in reality among creatures.[109]

What does it mean to say that there is a multiplicity of rationes in God? Aquinas addresses this question in an earlier article of the Commentary devoted to the question, ‘Whether the plurality of rationes by which the attributes differ is solely in the intellect or also in God’.[110] There he first distinguishes three ways in which a conception in the intellect can relate to an object outside of the soul. The first is when it is a likeness (similitudo) of the thing, as, for example, the conception ‘man’ is of a man. In such a case the conception has an immediate fundamentum in re, inasmuch as the thing itself makes the intellect true.[111] The second is when the conception is not a likeness of the thing but nonetheless follows from the manner of understanding (ex modo intelligendi) that thing, as when man is identified as an animal (something that never exists, simply as such, in reality) and mathematical entities are formed by abstraction. In such a case the conception has a remote fundamentum in re, and the intellect is at least not false. The third case is when there is no fundamentum in re, as with fictional objects, and in such a case the conception is simply false.

Of these three cases, the sort that applies to our conceptions of the divine attributes is the first; and it is in such cases that the ratio is properly said to be in the object.[112] Indeed, the perfections attributed to God are more properly and fully in the divine essence than in creatures. Aquinas cites three signs of this: they are all present together, they are without any defect, and they form a unity, ‘for the things that are diverse in creatures are one in God’. For Aquinas, then, the real unity of the divine attributes is a sign that the perfections are more fully real, and their rationes more fully present, in God than in creatures. This means that, although the distinction among them is not ‘real’, in an important sense it is not mind-dependent. As Aquinas observes elsewhere, ‘even if from eternity creatures had never been, and even if future things were never to be, it was true to say that God is wise, good, and other things of this sort’.[113]

Aquinas reiterates this view of the divine attributes frequently.[114] In the Summa Contra Gentiles he adds a helpful analogy designed to illustrate how multiple attributes can pre-exist as a unity in their source. The analogy is based on the different ways that heat and dryness exist in fire and in the sun:

Through the same power through which it produces heat, the sun produces also many other effects among sublunary bodies—for example, dryness. And thus heat and dryness, which in fire are diverse qualities, belong to the sun through one and the same power. So, too, the perfections of all things, which belong to the rest of things through diverse forms, must be attributed to God through one and the same power in Him.[115]

One must bear in mind that, in Aristotelian physics, heat and dryness are real qualities that are constitutive of fire, just as heat and wetness are constitutive of air and coolness and dryness of earth. The sun is not made of fire, but of ether, and so does not possess these qualities in the same way as fire; yet clearly it does possess them in some higher mode, for otherwise it could not produce them among bodies.[116] We thus apply these terms to the sun, but in a way that bears only an analogical relationship to their application to fire and other sublunary bodies.

The Scholastic Distinctions: Development and Controversy

These are the beginnings of what became, in later scholasticism, a baroquely complex system of distinctions. Although Aquinas does distinguish between the real and rational distinction, as well as (implicitly, at least) two types of each, it is far from clear that he intended this classification to be exhaustive. He often speaks of two things as different or distinct without attempting to identify precisely the kind of distinction he has in mind, and in his voluminous works he does not devote even a single article to dealing with distinctions as a topic in their own right.[117]

The immediate catalyst for later developments was the work of Giles of Rome, a student of Aquinas who became one of his sharpest critics. Shortly after Aquinas’ death, Giles began advancing the view that there is a real distinction between essence and existence (esse) in creatures, and that these are in fact two distinct res, at least one of which (essence) exists separately from the other in the divine mind.[118] Giles’ views provoked numerous rebuttals, and these naturally devoted considerable attention to the question of precisely what kind of distinction there is between essence and existence, if it is not one that is ‘real’ in Giles’ sense. It is noteworthy that Aquinas himself never said that there is a real distinction between essence and existence, and for several decades after his death such a view was not widely attributed to him. Later, however, the belief in a real distinction between essence and existence (albeit not in Giles’ sense) came to be seen as a cornerstone of orthodox Thomism.[119]

Thanks largely to this controversy, both Thomists and their rivals began to develop increasingly subtle and sophisticated accounts of the various kinds of distinction. The following is what became the standard Thomistic breakdown.[120]

1. Real—obtains independently of the mind
2. Absolute (‘real major’)—between two entities (res) that are ‘nonidentical as things in their own right, prior to and independent of any objectifying insight or construction elicited by the human reason’ (Glanville).
3. Material—e.g., two individuals of same species; different material parts of a single individual.
4. Formal—e.g., essences or natures of different species; a substance and its accidents (understood as universals); different accidents (again, qua universal); the essence and the act of existence (esse) of an individual entity; the Persons of the Trinity.
5. Modal (‘real minor’)—between an entity and its modes, or among the modes.
6. Between a thing and its mode of being or acting—e.g., Socrates and his being seated; the soul and its faculties; a continuum and its indivisible elements (e.g., line/points).
7. Between two modes of the same thing—e.g., Socrates’ being seated and his being in prison.
8. Between primary matter and substantial form.
9. Rational—obtains only in virtue of being thought by a mind
10. Greater (distinctio rationis ratiocinatae, ‘distinction of reason reasoned about’, a.k.a. ‘virtual’ or ‘with foundation in reality’)—originates both in the mind and in the object, i.e., the relatum considered by the mind has intrinsic intelligible content which is ‘rendered positively and actually [distinct] by the abstractive power of the mind’ (Glanville).
11. Major (or imperfect)—between two things the concept of one of which includes the other, but not vice versa, e.g., an individual and its successive essential attributes, such as Socrates, and his humanity, rationality, life, etc.; the divine perfections, e.g., goodness and wisdom; a divine Person and the divine essence.
12. Minor (or perfect)—between two things the concept of each of which includes the other, e.g., 5+7 and 12; being and substance; the principle of intellectual life and the principle of animal life in man.
13. Lesser (distinctio rationis ratiocinates, ‘distinction of reason reasoning’, a.k.a. ‘without foundation in reality’)—originates exclusively in the mind, e.g., man and rational animal; different essential attributes (qua universal) of an individual, such as ‘body’, ‘animal’, ‘living’, and ‘man’ said of Socrates; the negative divine attributes; the relational divine attributes; the divine intellect and its act; the divine will and its act.

III. Notional—also obtains only in virtue of being thought by a mind, and more specifically in virtue of different names conventionally applied to a single reality, e.g., Tully vs. Cicero, tunic vs. cloak, man (qua species) vs. rational animal.

Many questions could be asked about this breakdown, particularly as it relates to the distinction of essence and existence.[121] Perhaps the most significant for our purposes is that of precisely what is entailed by the presence of a greater or ‘virtual’ rational distinction. Is it really true that such a distinction obtains only in virtue of being thought by a mind, when it merely elucidates the intelligible content (ratio) that is intrinsic to the object? After all, as we have seen, Aquinas holds that a statement attributing to God a plurality of divine attributes would be true even if there never had been, and never were to be, any created minds.

It was in part to address this question that Scotus introduced his famous formal distinction.[122] Scotus defines two items as formally distinct when they cannot exist separately (and thus are not ‘really distinct’, as he uses that term) but nonetheless can be defined or understood separately, in the sense that each can be defined or understood without reference to the other.[123] Scotus holds that, in order for such a distinction to hold, there must be a ‘formality’ (formalitas, ‘little form’) of each of the distinct items in the object prior to its being cognized by the mind. Such a formality should not be conceived as an ontological constituent in the same way as matter and form, but it is nonetheless distinct prior to its cognition by the mind. Scotists see this conclusion as merely drawing out the implications of Aquinas’ own admission of the objectivity of the greater rational distinction.

Scotus’ formal distinction thus effectively replaces the Thomistic greater rational distinction, although it also incorporates some cases that Thomists regard as belonging to the real distinction.[124] Prominent examples of the formal distinction include that between the soul and its faculties; that of successive essential attributes; that among the divine attributes and between any particular divine attribute and the divine essence; that between a divine Person and the divine essence; and that between being and its transcendental attributes, such as unity, truth, and goodness. In addition, Scotus posited a ‘modal’ formal distinction holding between a form and its mode, such as that between wisdom and infinite in God or between being and finite in creatures.

Another important question that can be posed regarding the Thomistic distinctions pertains to their application to the Trinity. Aquinas holds that each of the divine Persons is really distinct from the others but really identical with (and only rationally distinct from) the divine essence. This raises the question of how two items can be really identical to some third item, but not to one another; or in other words, how real ‘real identity’ actually is, given that it is not transitive. Certainly we move here beyond the realm of Aristotle’s relatively intuitive concept, which does obey such a rule; if the roads from A to B and from C to D are both really identical to Route 89, for example, they are really identical to one another. Suarez was admirably forthright about the oddity of this special exemption in the case of the Trinity:

If two things are in reality identical with a third thing, they will also be identical with each other in reality, although they may be diverse in concept… In creatures and in finite things this principle avails absolutely. But in an infinite thing, such as is the divine essence, the maxim is not verified, absolutely speaking, since on account of its infinity the divine essence can be identical with opposite relations which, because of this opposition, cannot be identical with one another, except in the essence alone.[125]

It is hard to know what to make of this claim that infinity enables an essence to be really identical with opposites, which yet remain not really identical with one another. If infinity can work such magic in the case of the divine essence, why can it not equally do so in the case of the divine Persons, who are also infinite—and, indeed, really identical to the essence?

One might suppose that this is simply part of the mystery of the Trinity. Yet that the Persons are really distinct from one another but really identical with the essence is hardly de fide, even for Roman Catholics. It is merely one formulation among others of Trinitarian doctrine, one that arose in the specific historical circumstance of the attempt to develop Peter Lombard’s Trinitarian theology (including the quaedam summa res) using Aristotelian terminology.

Scotus, at any rate, thought that there was a better option. In his view each of the Persons is only formally distinct from the essence.[126] Each is thus also ‘really identical’ with the essence, in the limited sense of being unable to exist separately from it; but real identity in this sense (which is very different from Aristotle’s) clearly is not transitive, and so does not threaten the distinction of the Persons.

What kind of distinction?

We can now turn at last to the question of the application of these various distinctions to that between essence and energies. It has often been observed that Palamas seems to have deliberately refrained from describing the essence-energies distinction as kat’ epinoian.[127] In light of the history we have observed, this should surely be no surprise. The range of items traditionally described as distinct kat’ epinoian is immense. It includes (within theology alone) the names of Christ, the divine attributes, the Persons of the Trinity, the two natures of Christ, the flesh of Christ and the Word, and the human body and soul. Plainly this is an extremely heterogeneous grouping, and much that is true in any particular case does not carry over to the others. The Persons of the Trinity and the two natures of Christ, for example, exist as distinct in full actuality prior to any act of human thought, whereas the same cannot be said (according to Maximus, at least) of the body and soul. On the other hand, the body and soul can, after their initial union, exist apart from one another, whereas the same is not true of the divine Persons or the two natures. Because of this heterogeneity, to describe a distinction as kat’ epinoian can invite considerable confusion, as occurred in regard to the two natures of Christ, and, to a lesser extent, the Persons of the Trinity.

What all this shows is that to speak of two things as distinct kat’ epinoian is, taken alone, not an ontological statement at all. It is an epistemological statement, in that it identifies the means by which we conceive or recognize them as distinct—that is, through reflection rather than sense experience. As we have seen, this is the original meaning of the term as far back as the Stoics, and it is clearly expressed in the general discussions of epinoia by Basil and Gregory of Nyssa. It is for this reason that unity can also be kat’ epinoian, as is true (according to Theodore of Raithu and John Damascene) of the human race. Confusion enters because the term epinoia is also used in statements that do have ontological significance, as when something is said to be conceived by bare epinoia (meaning in the imagination) or to exist in epinoia and not in reality. Careful attention must be paid to the specific locution, as well the context, to discern the author’s meaning in a particular case.

Taking the term in its epistemological sense, it is certainly true that the essence-energies distinction is kat’ epinoian since both concepts involved are formed through reflection. But to say this is not very helpful as regards the ontological issues that are generally of interest. Furthermore—as the controversies enshrined in the Synodikon illustrate—it can invite confusion by seeming to suggest that we can intelligibly ask what the essence would be like apart from the energies, or vice versa. As Palamas never tires of reiterating, no essence can exist without its natural energies, nor can an energy exist without being the active manifestation of some essence. I would suggest that it was primarily to avoid such potential confusions that Palamas quietly eschewed referring to epinoia.

His immediate followers, such as Kokkinos and Kantakouzenos, were less cautious. No doubt, as Demetracopoulos and Lévy have observed, they wished for polemical reasons to emphasize as clearly as they could the limited character of the distinction. This seems a sufficient explanation in the case of Kokkinos, who wrote prior to the appearance of the Greek translations of Aquinas.[128] The case of Kantakouzenos is more complex, since he may have intended his usage of epinoia to be understood in light of that given to it in these translations. On the basis of evidence so far presented, however, I am not yet convinced that there is truly a substantive difference between him and his predecessors.[129] More work will be needed to determine precisely the effect of the Thomistic translations on the unfolding of Palamism.

This brings us to the second set of distinctions, those of the scholastics, and the question of whether and how they can be correlated with those of the East. There is an unfortunate tendency to take the scholastic distinctions as if they were simply a known and fixed quantity, the only debatable question being that of how those of the East (the essence-energies distinction and that kat’ epinoian) relate to them. This is very far from the case. Not only have the scholastic distinctions been the subject of interminable controversy, among Thomists, Scotists, Suarezians, and others; the history we have surveyed reveals several points at which the fundamental line of thought behind them can and should be brought into question.

One must note, first of all, the sheer happenstance involved in the problem which triggered this development, that of making sense of Peter Lombard’s Trinitarian theology. Viewed from a patristic standpoint there is nothing necessary or even very plausible about the idea that the divine essence is quaedam summa res, while each of the Persons is a res that is identical to the essence although not identical to the others. This is a formulation that is found in none of the Fathers, East or West, and is far removed from the subtlety and complexity of their thought. It bequeathed to the scholastics the problem of explaining how such an apparently contradictory set of statements could possibly be true. It is not surprising that they turned to Aristotle for help, and specifically to the Aristotelian distinction between separability in definition (λόγος) and in being (τὸ εἶναι). In reality, however, this Aristotelian distinction is not very helpful, since Aristotelian ‘real’ identity (that is, identity in being) is transitive.

To the perplexities thus generated, a further set were soon added in the attempt to expand the rather ad hoc distinctions drawn by Aquinas into a comprehensive system that would embrace all distinctions whatsoever. As noted earlier, Aquinas neither says nor implies that every distinction must fit into his own three categories of real, rational, and notional.[130] This is an assumption that entered through the heat of the controversy sparked by Giles of Rome over the nature of the distinction between essence and existence. The central question is whether ‘obtaining in virtue of being thought by a mind’ is the sort of predicate about whose application there is always some decisive fact of the matter, or whether instead it is one to which there may be, in principle, no clear answer as to whether it applies or not. It is important to note that many predicates are indeterminate to some degree. Most familiarly, this includes those that are vague, such as ‘heap’, ‘crowd’, ‘beard’, or ‘ill’. But there are other types as well, such as those that depend for their truth on some presupposed reference frame or point of view. It is true that stars twinkle if one has in mind how they appear from the earth, but not if one has in mind their appearance from space; and the same is true of other commonplace statements, such as that the planets have retrograde motion and the sun rises in the east. A further class of predicates apply only when one presupposes some important but unstated qualification. When I point to a photo and say, ‘that is Helen’, my statement may well be true, but only if understood with the implicit qualification that it is her photo, not the actual person.

Bearing all this in mind, the assumption that ‘obtains in virtue of being thought by a mind’ neatly divides possible distinctions into two disjoint and mutually exhaustive classes is decidedly one that requires to be supported by argument. So far as I am aware, such argument has not been forthcoming. In fact, I would go further and suggest that, from a theistic point of view, there should be at least a prima facie presumption that it is false. All distinctions, including those that are merely notional or verbal, have (on the traditional view of foreknowledge) been known to God from all eternity. Is it really true, then, that some of them obtain only in virtue of being thought by a human mind? Why is divine thought not enough? If the answer is that God thinks them only because we (in the causal order) think them first, is not God then passive with respect to the content of His own thought? That seems an awkward conclusion, especially if God is actus purus. Why not say instead that our ability to think them is derivative from the divine thought, and that they exist already actually—although, no doubt, with different degrees and forms of actuality—in the divine mind? But then almost all distinctions would hold in virtue of being thought by a mind, either divine or human, although the extent and degree to which human thought recognizes them may vary greatly.[131]

I merely raise this issue as a way of indicating how fraught with difficulties the traditional scholastic categorization of distinctions actually is. Surely, then, we should be cautious in applying it to the essence-energies distinction, lest in doing so we merely compound one source of obscurity upon another. This is not to say that some comparisons may not be useful in some cases. I would agree with Spencer that the Scotistic formal distinction is the nearest correlative among the scholastics to Palamas’ distinction between the divine essence and what Palamas calls God’s natural energies, such as goodness, being, life, wisdom, and power.[132] However, that is not to say that these simply are the same distinction. For Palamas it is crucial that the natural energies precisely are energies (ἐνέργειαι) and thus are acts that God performs. For this reason creatures can participate in them, just as they can, for example, in the gifts of the Spirit.[133] Palamas operates with a very different conceptual framework than does Scotus, and in drawing comparisons between them we must not lose sight of these broader differences.

The best general description of the essence-energies distinction remains that which is implied by the meaning of the word energeia itself: it is the distinction between an agent and that agent’s activity. In the case of God, however, we must recognize that the range of His energeiai is extremely diverse. As I have pointed out elsewhere, some are eternal and others temporal; some are contingent and others necessary; some are best conceived as ‘realities’ or ‘energies’, others as activities or operations, and yet others as attributes.[134] Rather than seeking to fit this multiform concept into categories that are foreign to it, we ought to seek to understand it in its own terms, in light of the sources and concerns that shaped Palamas’ thought. Only in this way can we truly learn what he has to teach us.[135]

 

^[1]  Martin Jugie, ‘Palamas, Grégoire’, Dictionnaire de théologie catholique, vol. 11, pt. 2 (Paris: Letouzey et Ané, 1932), col. 1735–76, esp. col. 1750, 1755–56, 1760–64.

 

^[2]  Sébastien Guichardan, Le problème de la simplicité divine en orient et en occident au XIVe et XVe siècles: Grégoire Palamas, Duns Scot, Georges Scholarios (Lyons: Anciens Établissements Legendre, 1933), 93, 105–109. The largely critical review of this work by Vénance Grumel, Echos d’Orient 34 (1935): 84–96, repeats this point without criticism.

 

^[3]  For example, Basil Krivosheine, The Ascetic and Theological Teaching of Gregory Palamas (London: Coldwell; reprint from The Eastern Churches Quarterly, 1938), 32; Vladimir Lossky, The Mystical Theology of the Eastern Church (Crestwood: St. Vladimir’s Seminary Press, 1976; orig. pub. in French, 1944), 76–77 and ‘The Theology of Light in the Thought of St. Gregory Palamas’ (orig. pub. in French, 1945) in idem, In the Image and Likeness of God (Crestwood: St. Vladimir’s Seminary Press, 1974), 45–69, at 56; Georges Florovsky, ‘St. Gregory Palamas and the Tradition of the Fathers,’ Greek Orthodox Theological Review 5 (1959/60): 119–31, at 130; idem, ‘St. Athanasius’ Concept of Creation’, Studia Patristica 6 (1962): 36–57, at 57; John Romanides, ‘Notes on the Palamite Controversy and Related Topics’, Greek Orthodox Theological Review 6 (1960/61): 186–205, at 190; Kallistos Ware, ‘God Hidden and Revealed: The Apophatic Way and the Essence-Energies Distinction’, Eastern Churches Review 7 (1975): 125–36, at 134; Gerry Russo, ‘Rahner and Palamas: A Unity of Grace’, St. Vladimir’s Theological Quarterly 32 (1988): 157–80, at 175 (but cf. 178); Joost van Rossum, ‘Deification in Palamas and Aquinas’, St. Vladimir’s Theological Quarterly 47 (2003): 365–82, at 371, 373. Of these authors, Krivosheine, accepts the identification with a real minor distinction, but says it is ‘merely analogical’. Ware cites from Krivosheine the alleged statement of Palamas that the distinction is a πραγματικὴ διὰκρισις, but Krivosheine cites no source and in more recent writings Ware has not, so far as I am aware, repeated this claim. The others speak of a ‘real distinction’ without further definition.

 

^[4]  Martin Jugie, ‘Palamite (controverse)’, Dictionnaire de théologie catholique, vol. 11, pt. 2 (Paris: Letouzey et Ané, 1932), col. 1777–1818, at 1800–01; S. Guichardan, Le problème de la simplicité divine, 188–90, 204–05. See also the thorough discussion in Christiaan Kappes, The Theology of the Divine Essence and Energies in George-Gennadios Scholarios (PhD dissertation, University of Thessaloniki, 2017), available at https://bcs-us.academia.edu/ChristiaanKappes (accessed September 2018).

 

^[5]  Gérard Philips, ‘La grâce chez les orientaux’, Ephemerides Theologicae Lovanienses 48 (1972): 37–50, at 38, 47; Juan-Miguel Garrigues, ‘L’énergie divine et la grâce chez Maxime le Confesseur’, Istina 19 (1974): 272–96, at 280; Georges Barrois, ‘Palamism Revisited’, St. Vladimir’s Theological Quarterly 19 (1975): 211–31, at 223; David Coffey, ‘The Palamite Doctrine of God: A New Perspective’, St. Vladimir’s Theological Quarterly 32 (1988): 329–58, at 334–35.

 

^[6]  See John Milbank, ‘Ecumenical Orthodoxy: A Response to Nicholas Loudovikos’ in Encounter between Eastern Orthodoxy and Radical Orthodoxy, eds A. Pabst and C. Schneider (Burlington: Ashgate, 2009), 156–64; idem, ‘Christianity and Platonism in East and West’ in Divine Essence and Divine Energies: Ecumenical Reflections on the Presence of God in Eastern Orthodoxy, eds C. Athanasopoulos and C. Schneider (Cambridge: James Clarke, 2013), 158–209; Nikolaos Loudovikos, ‘Striving for Participation: Palamite Analogy as Dialogical Syn-energy and Thomist Analogy as Emanational Similitude’, Divine Essence and Divine Energies, 122–48; idem, ‘Being and Essence Revisited: Reciprocal Logoi and Energies in Maximus the Confessor and Thomas Aquinas, and the Genesis of the Self-referring Subject’, Revista Portuguesa de Filosofia 72 (2016): 117–46. Christian Kaapes, J. Isaac Godd, and T. Alexander Giltner, ‘Palamas among the Scholastics: A Review Essay Discussing D. Bradshaw, C. Athanasopoulos, C. Schneider et al., Divine Essence and Divine Energies’, Logos: A Journal of Eastern Christian Studies 55 (2014): 175–220 also points to numerous parallels between Palamas and Scotus, although without specifically addressing the nature of the essence-energies distinction.

 

^[7]  Mark K. Spencer, ‘The Flexibility of Divine Simplicity: Aquinas, Scotus, Palamas’, International Philosophical Quarterly 57 (2017): 123–39.

 

^[8]  M. Jugie, ‘Palamite (controverse)’ (above, n. 4).

 

^[9]  John A. Demetracopoulos, ‘Palamas Transformed: Palamite Interpretations of the Distinction between God’s ‘‘Essence’’ and ‘‘Energies’’ in Late Byzantium’ in Greeks, Latins, and Intellectual History 1204–1500, eds M. Hinterberger and C. Schabel (Leuven: Peeters, 2011), 263–372.

 

^[10]  See J.A. Demetracopoulos, ‘Palamas Transformed’, 272–76, 291–92. He also includes in this group the later Palamite, Joseph Bryennios (287–91).

 

^[11]  See J.A. Demetracopoulos, ‘Palamas Transformed’, 292–305, 369–70.

 

^[12]  See Antoine Lévy, ‘Lost in Translatio? Diakrisis kat’ epinoian as a Main Issue in the Discussions between Fourteenth-century Palamites and Thomists’, The Thomist 76 (2012): 431–71, esp. 434–41, 467–71.

 

^[13]  See N. Loudovikos, ‘Striving for Participation’, 127; idem, ‘Being and Essence’, 121. See also Anna Williams, The Ground of Union: Deification in Aquinas and Palamas (Oxford: Oxford University Press, 1999), 139–48, which suggests (without quite asserting) that the distinction is ‘nominal’ rather than ‘real’.

 

^[14]  For example, John Meyendorff, A Study of Gregory Palamas (Crestwood: St. Vladimir’s Seminary Press, 1974; orig. published in French, 1959), 225–27; André de Halleux, ‘Palamisme et scolastique: exclusivisme dogmatique ou pluriformité théologique?’ Revue théologique de Louvain 4 (1973): 409–42. Many of the authors cited earlier (especially among the Orthodox) would probably also hold this view, although they use scholastic terminology as a concession to western audiences.

 

^[15]  See G. Christopher Stead, ‘Logic and the Application of Names to God’ in L.F. Mateos Seco and J.L. Bastero, eds, El Contra Eunomium I’ en la producción literaria de Gregorio de Nisa: VI Coloquio Internacional sobre Gregorio de Nisa (Pamplona: Ediciones Universidad de Navarra, 1988), 303–20; Richard Paul Vaggione, Eunomius of Cyzicus and the Nicene Revolution (Oxford: Oxford University Press, 2000), 241–45; Lewis Ayres, Nicaea and Its Legacy: An Approach to Fourth-century Trinitarian Theology (Oxford: Oxford University Press, 2004), 192–94; John A. Demetracopoulos, ‘Glossogony or Epistemology? Eunomius of Cyzicus’ and Basil of Caesarea’s Stoic Concept of ΕΠΙΝΟΙΑ and Its Misrepresentation by Gregory of Nyssa’, Gregory of Nyssa: Contra Eunomium II, eds L. Karfíková, S. Douglass, and J. Zachhuber (Leiden: Brill, 2007), 387–97; Andrew Radde-Gallwitz, Basil of Caesarea, Gregory of Nyssa, and the Transformation of Divine Simplicity (Oxford: Oxford University Press, 2009), 59–66, 149–52; Mark Delcogliano, Basil of Caesarea’s Anti-Eunomian Theory of Names (Leiden: Brill, 2010), 163–64, 171–76.

 

^[16]  G.C. Stead, ‘Logic’, 311.

 

^[17]  Philo of Alexandria, Who Is the Heir of Divine Things 22–23; cf. G.C. Stead, ‘Logic’, 311–12. Another citation offered by G.C. Stead (Questions on Exodus II.63) appears to be a mistake, as the phrase quoted does not appear in the text.

 

^[18]  Plotinus, Enneads VI.2.3.22–23.

 

^[19]  Plotinus, Enneads VI.2.7–8.

 

^[20]  Compare the discussion of this passage in J.A. Demetracopoulos, ‘Glossogony’, 389–90.

 

^[21]  Origen remains non-committal, however, regarding precisely which of these titles (other than Wisdom) would have applied to the Son in the absence of the Incarnation; see Origen, Commentary on John I.19.118–1.20.123.

 

^[22]  Methodius of Olympus, On Resurrection III.6 (GCS 27:397). My thanks to Christiaan Kappes for drawing my attention to this passage.

 

^[23]  See further examples and discussion in Regiland Eldred Witt, ‘ὙΠΟΣΤΑΣΙΣ’, in Amicitiae Corolla: A Volume of Essays Presented to James Rendel Harris, ed. H.G. Wood (London: University of London Press, 1933), 319–43. As Witt notes, this distinction is also found in Philo and Origen.

 

^[24]  Basil of Caesarea, Against Eunomius I.6. For the Greek see Contre Eunome, vol. 1, eds B. Sesboüé et al. (Paris: Cerf, 1982), 184.22–25, and for the English Mark DelCogliano and Andrew Radde-Gallwitz, trans., St. Basil of Caesarea: Against Eunomius (Washington, D.C.: Catholic University of America Press, 2011), 97.

 

^[25]  Basil, Against Eunomius I.6 (Sesboüé 186.42–43; DelCogliano 98).

 

^[26]  Basil, Against Eunomius I.7 (Sesboüé 192; DelCogliano 100).

 

^[27]  Basil, Against Eunomius I.8 (Sesboüé 194.24–25; DelCogliano 101).

 

^[28]  Basil, Against Eunomius I.14 (Sesboüé 220; DelCogliano 113). The Against Eunomius leaves it unclear whether the terms said of God are merely formed from observing the activities (as ‘hydrogen’ names something involved in the process of making water) or actually name the activities or operations themselves. I believe Basil’s Epistle 234 makes it clear that he intends the latter, but nothing hinges on that here.

 

^[29]  Basil, Against Eunomius I.20 (Sesboüé 246; DelCogliano 121, slightly modified).

 

^[30]  For the lack of diastēma see Basil, Epistle 38.3–4 (a work that, even if in fact by his brother Gregory, was regarded as Basil’s by the Byzantines).

 

^[31]  For the attribution to Didymus see Joseph Lebon, ‘Le Pseudo-Basile (Adv. Eunom. IV-V) est bien Didyme d’Alexandrie’, Muséon 50 (1938): 61–83. More recently, F.X. Risch has argued that the author was Apollinaris of Laodicea and that these works actually antedate Books I–III; see France X. Risch, Pseudo-Basilius: Adversus Eunomium IV-V, Einleitung, Übersetzung und Kommentar (Leiden: Brill, 1992), and Thomas Böhm, ‘Basil of Caesarea, Adversus Eunomium I–III and Pseudo-Basil, Adversus Eunomium IV–V’, Studia Patristica 37 (2001): 20–26.

 

^[32]  Pseudo-Basil, Against Eunomius IV (PG 29:704C).

 

^[33]  Gregory Nazianzen, Orations 30.8 (citing Eph. 1:17), ed. P. Gallay, Grégoire de Nazianze: Discours 27–31 (Paris: Cerf, 2006), 242; trans. NPNF II.7, 312.

 

^[34]  Gregory Nazianzen, Orations 29.13; cf. Orations 23.11, where each of the Persons is God ‘if contemplated alone, the mind dividing (τοῦ νοῦ χωρίζοντος) things that are indivisible’ (PG 35:1164A).

 

^[35]  Gregory Nazianzen, Orations 31.15.

 

^[36]  I use the Latin version of the title to avoid confusion with Basil’s work of the same name.

 

^[37]  For more detail see the papers collected in L. Karfíková, S. Douglass, and J. Zachhuber, eds, Gregory of Nyssa: Contra Eunomium II (Leiden: Brill, 2007).

 

^[38]  Gregory of Nyssa, Contra Eunomium (= C.E.) II.168 (GNO 1, 274; trans. NPNF II.5, 266).

 

^[39]  Gregory of Nyssa, C.E. II.182 (GNO 1, 277; trans. NPNF II.5, 268).

 

^[40]  Gregory of Nyssa, C.E. II.190 (GNO 1, 279; trans. NPNF II.5, 268).

 

^[41]  Gregory of Nyssa, C.E. II.150–52 (GNO 1, 269; trans. NPNF II.5, 265).

 

^[42]  Gregory of Nyssa, C.E. II.585 (GNO 1, 397; trans. NPNF II.5, 309). For this etymology and other similar passages in Gregory, see my Aristotle East and West: Metaphysics and the Division of Christendom (Cambridge: Cambridge University Press, 2004), 162–64.

 

^[43]  Gregory of Nyssa, C.E. II.298–99 (GNO 1, 314; trans. NPNF II.5, 280).

 

^[44]  Gregory of Nyssa, C.E. I.691 (GNO 1, 224–25; trans. NPNF II.5, 100).

 

^[45]  Cyril of Alexandria, Commentary on John I.3 (PG 73:53B–C). See also similar analogies at I.5 85A (light and its radiance) and II.1 213C (fire and its heat), as well as Thesaurus 4 (PG 75:44C) (fire and light) and 12 184A (sun and its radiance), all said to be distinguished tēi epinoiai.

 

^[46]  One might object that these analogies seem inadequate, since the relation of the Son to the Father is causal whereas sweetness is in the honey and heat in the fire as propria (that is, essential accidents) in their subject. (I thank Mark Spencer for raising this objection.) Cyril, however, does seem to think of heat as caused by the fire, as indicated by his referring to it as naturally proceeding (φυσικῶς προιοῦσα) from the fire (53B). Presumably he would say the same of the sweetness of the honey. In Plotinian terms these are cases of external rather than internal act; see D. Bradshaw, Aristotle East and West, 76–78.

 

^[47]  Leontius of Byzantium, Solution to the Objections of Severus (PG 86:1937C; cf. 1932C).

 

^[48]  Eustathius Monachus, Epistuala de Duabus Naturis (PG 86:921D).

 

^[49]  Theodore of Raithu in F. Diekamp, ed., Analecta Patristica:Texte und Abhandlungen zur griechischen Patristik (Rome: Pontificale Institutum Orientalium Studiorum, 1938), 215.

 

^[50]  Justinian, Confessio Rectae Fidei (PG 86:1005C). For a translation see Kenneth Paul Wesche, On the Person of Christ: The Christology of Emperor Justinian (Crestwood: St. Vladimir’s Seminary Press, 1991), 174.

 

^[51]  Leontius of Byzantium, Solution to the Objections of Severus (PG 86:1937C).

 

^[52]  Pamphilius Theologicus, Panoplia Dogmatica 9.4, cited in G.W.H. Lampe, ed., A Patristic Greek Lexicon (Oxford: Clarendon Press, 1961), s.v. epinoia 3.

 

^[53]  Leontius of Jerusalem, Aporiae 58 (PG 86:1800D); trans. Patrick T.R. Gray, Leontius of Jerusalem: Against the Monophysites (Oxford: Oxford University Press, 2006), 217, slightly modified.

 

^[54]  See Brian Daley, ‘Boethius’ Theological Tracts and Early Byzantine Scholasticism’, Mediaeval Studies 46 (1984): 158–91; also, from a more critical standpoint, Dirk Krausmüller, ‘Aristotelianism and the Disintegration of the Late Antique Theological Discourse’ in J. Lössl and J. W. Watt, eds, Interpreting the Bible in Late Antiquity (New York and London: Routledge, 2011), 151–64.

 

^[55]  Aristotle, Metaphysics IV.4 1027b25–31.

 

^[56]  For example, Physics III.3 202a18–21, b10–22, De Anima III.10 433b22–25, Nicomachean Ethics I.13 1100a28–32. It is also possible for something to be divided in its being but spatially and numerically one, as are the activity of the sensible object and the perceiving sense (De Anima III.2 425b26–426a1) and a given sense when it perceives contrary qualities (426b29–427a5). There thus seem to be three levels of separability: (1) in logos alone, (2) in logos and being, (3) in logos, being, and spatial/numeric. To these one may add the further elaborate distinctions among the three kinds of sameness and unity—numeric, specific, and generic—in Topics I.7, VII.1-2 and Metaphysics V.6, 9, X.3. It would appear that these two ways of classifying various types of unity and distinction are independent of one another.

 

^[57]  Porphyry, Isagoge, in A. Busse, ed., Commentaria in Aristotelem Graeca (CAG) (Berlin: Reimer, 1882–1909), vol. 4.1, 1.10–11. Precisely what Porphyry meant in referring to existing monais psilais epinoiais is a matter of dispute. Alain de Libera, La Querelle des universaux de Platon à la fin du Moyen Ậge (Paris: Vrin, 1996), 37, interprets this phrase as referring to a merely fictional existence, as opposed to that of entities that are conceptually distinguished but truly exist. Jonathan Barnes, Porphyry: Introduction (Oxford: Clarendon Press, 2003), 40–42, argues that the phrase simply means ‘depends on thought alone’ without distinction as to different types of mind-dependence.

 

^[58]  Ammonius, In Porphyrii Isagogen, CAG 4.3, 39.14–40.6, In Aristotelis De Interpretatione, CAG 4.5, 29.8–9; Elias, In Porphyrii Isagogen, CAG 18.1, 46.6–47.11, 49.17–20; David, In Porphyrii Isagogen, CAG 18.2, 108.24–109.9, 110.22–32, 114.2–5, 116.4–15.

 

^[59]  Ammonius, In Aristotelis De Interpretatione, CAG 4.5, 250.9–12; Elias, In Porphyrii Isagogen, CAG 18.1, 49.17–20; David, In Porphyrii Isagogen, CAG 18.2, 119.17–22. A somewhat different account of unqualified epinoia is offered by the unknown author known as Pseudo-Elias: whereas bare epinoia is the imagination of non-existent things such as the goat-stag, unqualified epinoia is that of a state of affairs that could be but is not, such as that I am currently in Alexandria or Athens; Pseudo-Elias (Pseudo-David): Lectures on Porphyry’s Isagoge, ed. L.G. Westerink (Amsterdam: North Holland Publishing, 1967), 29.6 (ed. Westerink, 66).

 

^[60]  David, In Porphyrii Isagogen, CAG 18.2, 205.20–26; Pseudo-Elias, Lectures 45.7–8 (ed. Westerink, 120).

 

^[61]  Ammonius, In Aristotelis De Interpretatione, CAG 4.5, 133.20–23; Elias, In Porphyrii Isagogen, CAG 18.1, 77.32–34.

 

^[62]  See Diogenes Laertius, Lives VII.135.

 

^[63]  See Alexander of Aphrodisias, In Aristotelis Metaphysica, CAG 1, 52.10–25, 228.29–231.25. Alexander is following here the teaching of Aristotle, Physics II.2 and Metaphysics XIII.2-3, although Aristotle does not refer to epinoia in this context.

 

^[64]  Pseudo-Elias, Lectures 18.19–21, 19.28 (ed. Westerink, 34, 38); cf. 36.11–13 (ed. Westerink, 94).

 

^[65]  Maximus the Confessor, Ambigua 7 (PG 91:1100C).

 

^[66]  Maximus the Confessor, Ambigua 7 (PG 91:1101B); trans. Nicholas Constas, On Difficulties in the Church Fathers: The Ambigua (Cambridge, Mass.: Harvard University Press, 2014), vol. 1, 139.

 

^[67]  Maximus the Confessor, Ambigua 42 1317C, 1320A; cf. further applications at 1324C–D, 1349A.

 

^[68]  John of Damascus, Dialectica 65, ed. P.B. Kotter, Die Schriften des Johannes von Damaskos (Berlin: De Gruyter, 1969–88), vol. 1, 135; trans. Frederic H. Chase, Saint John of Damascus: Writings (Washington, D.C.: Catholic University of America Press, 1958), 101.

 

^[69]  See Leontius of Byzantium, Solution to the Objections of Severus (PG 89:1932A–B). The Leontian version of the definition is also found in the short collection of philosophical chapters included by Kotter as an appendix to the Dialectica (Die Schriften des Johannes von Damaskos, vol. 1, 170–71) and in the Doctrina Patrum de Incarnatione Verbi (ed. F. Diekamp [Münster: Aschendorff, 1907], 198–99), where it is attributed to Leontius.

 

^[70]  Nikephoros Blemmydes, Epitome of Logic, chap. 5 (PG 142:724C–725B).

 

^[71]  For John’s view of universals see my ‘The Presence of Aristotle in Byzantine Theology’, The Cambridge Intellectual History of Byzantium, eds N. Siniossoglou and A. Kaldellis (Cambridge: Cambridge University Press, 2017), 381–96, at 389.

 

^[72]  John of Damascus, On the Orthodox Faith 8 (ed. P.B. Kotter, vol. 2, 28–29).

 

^[73]  It is possible that this passage in On the Orthodox Faith was influenced by a very similar passage in the Doctrina Patrum (ed. F. Diekamp, 188–90; cf. the direct verbal parallels noted by Kotter). The passage is attributed there to St Basil’s Short Rules, but this is almost certainly incorrect, both because of the anachronism involved and because such a discussion would be wholly out of place in the Short Rules. If the Doctrina Patrum dates from 685–726, as argued by Diekamp, then it seems more likely that John copied from the Doctrina than vice versa, although the latter cannot be excluded. At any rate, the attribution of this passage to Basil in the Byzantine period no doubt greatly enhanced its authority, as did its substantive agreement with Gregory Nazianzen, Orations 29.13 and 31.15 (cited above).

 

^[74]  John of Damascus, On the Orthodox Faith 65 (ed. P.B. Kotter, vol. 2,164; trans. F.H. Chase, 325), substantially repeated in chap. 91. As Kotter notes, the Damascene’s phrasing here seems to echo Cyril of Alexandria, who refers to the distinction between soul and body as perceived ἐν ἰσχναῖς θεωρίαις, ἤτοι νοῦ φαντασίαις (Ep. 46.5 [PG 77:245A]).

 

^[75]  John of Damascus, On the Orthodox Faith 91 (ed. P.B. Kotter, vol. 2, 217; trans. F.H. Chase, 383).

 

^[76]  For a brief account of these events and their significance see John Meyendorff, Christ in Eastern Christian Thought (Crestwood: St. Vladimir’s Seminary Press, 1975), 196–97, 200–01. So far as I am aware, their relevance to the essence-energies distinction was first observed by Norman Russell, ‘The Christological Context of Palamas’ Approach to Participation in God’ in Triune God: Incomprehensible but Knowable—The Philosophical and Theological Significance of St. Gregory Palamas for Contemporary Philosophy and Theology, ed. C. Athanasopoulos (Newcastle upon Tyne: Cambridge Scholars Publishing, 2015), 190–98.

 

^[77]  Jean Gouillard, ed., Le Synodikon de l’Orthodoxie: Édition et commentaire in Centre de recherche d’ histoire et civilisation Byzantines: Travaux et Mémoires 2 (1967): 71; cf. discussion, 206–10.

 

^[78]  Synodikon, ed. J. Gouillard, 79; cf. discussion, 221–23.

 

^[79]  Synodikon, ed. J. Gouillard, 79.

 

^[80]  Synodikon, ed. J. Gouillard, 81.

 

^[81]  V. Grumel, ed., Les regestes des actes du Patriarcat de Constantinople, vol. 1, fasc. 3 (Paris: Institut Français d’études Byzantines, 1932), 147, cited in N. Russell, ‘Christological Context’, 193.

 

^[82]  Niketas Stethatos, The Life of Saint Symeon the New Theologian, ed. and trans. R.P.H. Greenfield (Cambridge, Mass.: Harvard University Press, 2013), 172.

 

^[83]  See above, n. 34 (where the mind χωρίζοντος the three Persons) and n. 47 (where Christ’s humanity is χωρίζεται conceptually from his divinity).

 

^[84]  Symeon, Hymn XXI. 25–33, 307–11, 456–66, 477–79, in J. Koder, ed., Syméon le Nouveau Théologien. Hymnes. Tome II: Hymnes 16–40 (Paris: Cerf, 1971).

 

^[85]  This document was attributed by John Eugenikos to Patriarch Germanos the New (1223–1240), but is regarded by its modern editors, V. Laurent and J. Darrouzes, as more probably by George Moschabar. See V. Laurent and J. Darrouzes, Dossier Grec de l’union de Lyon (1273–1277) (Paris: Institut Français d’études Byzantines, 1976), 128–32 (discussion), 574–88 (text).

 

^[86]  V. Laurent and J. Darrouzes, Dossier Grec, 581.

 

^[87]  See J.A. Demetracopoulos, ‘Palamas Transformed’, 284 n. 58 (citing Makarios Chrysocephalos).

 

^[88]  Boethius, Second Commentary on the Isagoge I.11; CSEL vol. 48, 166–67.

 

^[89]  See also the even briefer remark in the Consolation of Philosophy that ‘everything which lies open to the senses, if you relate it to reason (ad rationem referas) is universal, but if you look at it by itself is singular’ (V.6.135; ed. and trans. S.J. Tester, Boethius: The Theological Tractates, The Consolation of Philosophy [Cambridge, Mass.: Harvard University Press, 1973], 430).

 

^[90]  John of Damascus, On the Orthodox Faith 8 (ed. P.B. Kotter, vol. 2, 28-29; trans. F.H. Chase, 185-86). For the Latin see E.M. Buytaert, ed., Saint John Damascene: De Fide Orthodoxa. Versions of Burgundio and Cerbanus (St. Bonaventure, N.Y.: Franciscan Institute, 1955), 42–44.

 

^[91]  Of the works discussed earlier, the only other one translated into Latin during the Middle Ages was the Dialectica, translated c. 1240 by Robert Grosseteste. Grosseteste transliterates rather than translating epinoia, adding an explanation based on the term’s etymology; see O.A. Colligan, ed., St. John Damascene: Dialectica. Version of Robert Grosseteste (St. Bonaventure, N.Y.: Franciscan Institute, 1953), 50.

 

^[92]  See Peter Lombard, Sentences I, Dist. 9.1, 23.5, 24.1.8–9.

 

^[93]  Peter Lombard, Sentences I, Dist. 5.1.6; ed. anon., Magistri Petri Lombardi: Sententiae in IV Libris Distinctae, Third edition, vol. 1, pt. 2 (Rome: Collegii S. Bonaventurae ad Claras Aquas, 1971), 82; cf. I, Dist. 1.2.4.

 

^[94]  Peter Lombard, Sentences I, Dist. 25.2.5, 34.4.1.

 

^[95]  Peter Lombard, Sentences I, Dist. 34.1.9; ed. anon., 250.

 

^[96]  See Fiona Robb, ‘The Fourth Lateran Council’s Definition of Trinitarian Orthodoxy’, Journal of Ecclesiastical History 48 (1997): 22–43; Isabel Iribarren, Durandus of St. Pourcain: A Dominican Theologian in the Shadow of Aquinas (Oxford: Oxford University Press, 2005), 19–28.

 

^[97]  ‘We… believe and confess with Peter Lombard that there is one highest, incomprehensible, and ineffable reality (res), which is truly Father, Son, and Holy Spirit; the three Persons together, and each Person distinctly (singillatim); therefore in God there is only Trinity, not a quaternity, because each of the Persons is that reality… Hence, though ‘‘the Father is one Person, the Son another Person, and the Holy Spirit another Person’’ [Gregory Nazianzen, Ep. 101], yet there is not another reality but what the Father is, this very same reality is also the Son, this is the Holy Spirit’. Heinrich Denzinger, Compendium of Creeds, Definitions, and Declarations on Matters of Faith and Morals, Forty-third edition (San Francisco: Ignatius Press, 2012), no. 804–5.

 

^[98]  See the comments upon the relevant texts by Aquinas: sunt diversa ratione, licet subiecto et magnitudine sint abinvicem inseparabilia (Commentary on the De Anima, Bk. III, Lect. 15, sect. 833); eadem secundum rem, sed differunt secundum rationem (Commentary on the Physics, Bk. III, Lect. 4, sect. 307). For text (and translation, where available) of Aquinas I use http://www.dhspriory.org/thomas (last accessed September 2018).

 

^[99]  For Bonaventure see Sandra Edwards, ‘St. Bonaventure on Distinctions’, Franciscan Studies 38 (1978): 194–212; I. Iribarren, Durandus of St. Pourcain, 51–59.

 

^[100]  Thomas Aquinas, Summa Theologiae (= S.T.), I, Q. 28, art. 2, Q. 39, art. 1.

 

^[101]  Thomas Aquinas, Commentary on the Sentences (= In Sent.) I, Dist. 22, Q. 1, art. 3; S.T. I, Q. 28, art. 3, Q. 30, art. 2, Q. 39, art. 1. Aquinas does not use this term frequently; in fact, its occurrences listed in the Thomas-Lexikon (available at http://www.corpusthomisticum.org, last accessed September 2018) all refer to the Persons of the Trinity.

 

^[102]  Thomas Aquinas, Summa Contra Gentiles (= S.C.G.) IV.24.9; S.T. I, Q. 40, art. 2.

 

^[103]  Thomas Aquinas, De Potentia Q. 10, art. 5; S.T. I, Q. 40, art. 2, Q. 47, art. 2. This is the familiar Aristotelian list of types of sameness or unity (above, n. 56).

 

^[104]  Thomas Aquinas, S.C.G. IV.14.15 and 24.7. The first of these passages affirms that there is ‘opposition of negation and affirmation’ in the Trinity, whereas the latter denies it, although affirming that there is ‘relative opposition in origin’. De Potentia Q. 10, art. 5 similarly speaks of relative opposition as necessary for a real distinction in God.

 

^[105]  Thomas Aquinas, In Sent. I, Dist. 2, Q. 1, art. 5, corpus and obj. 1.

 

^[106]  Thomas Aquinas, In Sent. I, Dist. 2, Q. 1, art. 5, ad 1. Aquinas refers here to his statement just previous that ‘The ratio of a relation is how it is referred to another. Relation in God can thus be understood two ways: either with reference to the essence, in which case it is ratio alone; or with reference to that to which it is referred, in which case each relation is really distinguished from the other by the proper ratio of relation’.

 

^[107]  Thomas Aquinas, S.T. I, Q. 30, art. 1, ad 2.

 

^[108]  Thomas Aquinas, In Sent. I, Dist. 22, Q. 1, art. 3 (numeration added).

 

^[109]  Thomas Aquinas, In Sent. I, Dist. 22, Q. 1, art. 3, ad 3.

 

^[110]  Thomas Aquinas, In Sent. I, Dist. 2, Q. 1, art. 3.

 

^[111]  Aquinas has in mind here the Aristotelian theory of cognition, on which the form of the object comes to be present in the soul as the object is cognized. For a contemporary exposition see John P. O’Callaghan, ‘The Problem of Language and Mental Representation in Aristotle and St. Thomas’, Review of Metaphysics 50 (1997): 499–545.

 

^[112]  A. Lévy (‘Lost in Translatio’, 460–61) says that it is the second of these three cases that fits our conceptions of God, but I can see no basis for this in the text, and it would fail to explain how the rationes are truly present in God. For an English translation of the entire article see Thomas Aquinas: Selected Philosophical Writings, ed. T. McDermott (Oxford: Oxford University Press, 1993), 230–40.

 

^[113]  Thomas Aquinas, In Sent. I, Dist. 2, Q. 1, art. 2; cf. the similar statement in De Potentia Q. 7, art. 6.

 

^[114]  See De Potentia Q. 7, art. 5–6; S.C.G. I.31; S.T. I, Q. 13, art. 2–4.

 

^[115]  Thomas Aquinas, S.C.G. I.31.2.

 

^[116]  This is an application of what is sometimes called the Principle of Causal Synonymy, that is, the principle that a cause must possess in some fashion the form it imparts, for otherwise the form would be created ex nihilo. For discussion see A.C. Lloyd, ‘The Principle that the Cause is Greater than Its Effect’, Phronesis 21 (1976): 146–56, and Alexander Mourelatos, ‘Aristotle’s Rationalist Account of Qualitative Interaction’, Phronesis 29 (1984): 1–16.

 

^[117]  He can also, on occasion, deliberately blur the difference among type of distinction; for example, S.C.G. IV.14.10 uses the identity of the divine attributes with the divine essence to argue for a similar identity between the Persons and the essence, without noting that the distinction among the attributes is rational whereas that among the Persons is real.

 

^[118]  See Francis A. Cunningham, S.J., Essence and Existence in Thomism: A Mental vs. the ‘Real Distinction?’ (Lanham, MD: University Press of America, 1988), 270–80; John F. Wippel, ‘Essence and Existence’, Cambridge History of Later Medieval Philosophy, eds N. Kretzmann, A. Kenny, and J. Pinborg (Cambridge: Cambridge University Press, 1982), 385–410.

 

^[119]  See F.A. Cunningham, Essence and Existence, for a thorough history of these developments.

 

^[120]  See Peter Coffey, Ontology or the Theory of Being (London: Longman, Green, and Co., 1929), 104–13, 139–53; Sandra Edwards, Medieval Theories of Distinction (PhD dissertation, University of Pennsylvania, 1974); John J. Glanville, ‘Distinctions, Kinds of’, New Catholic Encyclopedia (Washington, D.C.: Catholic University of America Press, 2003), vol. 4, 778–82; Edward Feser, Scholastic Metaphysics: A Contemporary Introduction (Lancaster: Editiones Scholasticae, 2014), 72–79. Much can also be gleaned from the short treatise of Francis Suarez, On the Various Kinds of Distinctions, trans. Cyril Vollert, S.J. (Milwaukee: Marquette University Press, 1947), although Suarez differs in some ways from the Thomists.

 

^[121]  Many Thomists would reject the characterization of an essence and its esse as two res, seeing this as precisely the error of Giles of Rome; presumably, they would then either characterize the real absolute distinction in a different way or place the distinction of essence and esse elsewhere, either as a real modal distinction (although it is hard to see how it could fit there) or a rational distinction. See Walter Patt, ‘Aquinas’ Real Distinction and Some Interpretations’, New Scholasticism 62 (1988): 1–29.

 

^[122]  The best introduction to this topic remains Allan Wolter, ‘The Formal Distinction’, Studies in Philosophy and the History of Philosophy, vol. 3: John Duns Scotus, 1265–1965 (Catholic University of America Press, 1965), 45–60, reprinted in idem, The Philosophical Theology of John Duns Scotus (Ithaca: Cornell University Press, 1990). See also Richard Cross, Duns Scotus (Oxford: Oxford University Press, 1999), 149; Peter King, ‘Scotus on Metaphysics’ in The Cambridge Companion to Duns Scotus, ed. T. Williams (Cambridge: Cambridge University Press), 15–68, at 21–26.

 

^[123]  ‘Definition’ here refers to an Aristotelian definition by genus and differentia. Many items can be understood and so have a ratio although they cannot be defined; for example, the highest genera, potencies, the four causes, and accidental unities, not to mention the Persons of the Trinity (P. King, ‘Scotus on Metaphysics’, 23).

 

^[124]  This point seems to me to argue against the suggestion which is sometimes made that the Scotistic formal distinction and the Thomistic greater rational distinction are really the same and differ only in emphasis. See also on this point the spirited critique by a Scotist, Michael Sullivan, of the account of distinctions in Feser’s Scholastic Metaphysics at http://lyfaber.blogspot.com/2014/06/fesers-scholastic-metaphysics-book_4.html (accessed September 2018).

 

^[125]  F. Suarez, On the Various Kinds of Distinctions III.8; trans. Vollert, 67.

 

^[126]  See A. Wolter, ‘The Formal Distinction’, 54; R. Cross, Duns Scotus, 69. In his late Parisian lectures, Scotus somewhat modified this view, holding that each Person is formally identical to the essence (inasmuch as the Person’s ratio cannot be specified without reference to the essence) but that the essence is formally distinct from each Person (inasmuch as its ratio can be specified without reference to the Person). This non-symmetric formal distinction is still sufficient to block the threatening inference. See Richard Cross, Duns Scotus on God (Aldershot: Ashgate, 2005), 235–40.

 

^[127]  For example, J.A. Demetracopoulos, ‘Palamas Transformed’, 278–79; N. Russell, ‘Christological Context’ passim.

 

^[128]  See J.A. Demetracopoulos, ‘Palamas Transformed’, 283–84, for Kokkinos’ assertion that essence and energies are distinguished conceptually (ἐπινοίᾳ) in his Fourteen Chapters against Barlaam and Akindynos, written probably in 1351. As Lévy observes, there are also repeated statements to this effect in his Antirrhetics against Gregoras of the mid-1350’s. One particularly interesting passage claims to find a precedent for this teaching in ‘Anastasius the Great’ (Discourse 5, ed. D. Kaimakes, Φιλοθέου Κοκκίνου δογματικὰ ἒργα, vol. 1 [Θεσσαλονίκη: Κέντρο Βυζαντινών Ερευνών, 1983), 164). Kaimakes cites no source for this reference, and the source cited by Lévy (the Logoi Dogmatikoi of Anastasius of Antioch, misidentified by Lévy as by Anastasius of Sinai; see A. Lévy, ‘Lost in Translatio’, 449) appears to be an error. If this source could be identified, it would provide further insight into why Kokkinos so readily adopted the terminology of epinoia.

 

^[129]  See J.A. Demetracopoulos, ‘Palamas Transformed’, 292–305, where a difference seems to be asserted rather than demonstrated.

 

^[130]  See on this point the comments of Sandra Edwards: ‘Is the real distinction a difference of real beings or principles which obtains independently of the mind? Unlike many of his successors Aquinas never presents such a general description, nor has he explicitly characterized all possible distinctions of real beings or intrinsic principles of such beings. For example, no mention is made of the distinction between a corporeal thing and its matter; the distinction between the accident of one thing, e.g., the whiteness of Peter, and another thing, Paul; the distinction between a substance which is created and its existence; and so on. Are these real distinctions also, and if so how do we determine that they are?’ S. Edwards, Medieval Theories of Distinction, 45. Later she adds further examples, such as those between a thing and a fictitious being (or any non-being) and between the matter of one entity and the form of another (86).

 

^[131]  I say ‘almost’ all because some distinctions in the Godhead, such as that among the Persons, do not hold only in virtue of being thought by God.

 

^[132]  See M.K. Spencer, ‘The Flexibility of Divine Simplicity’ (above, n. 7).

 

^[133]  Of course, these two forms of participation are different, as Palamas explains in his treatise On Divine and Deifying Participation.

 

^[134]  See D. Bradshaw, Aristotle East and West, 272.

 

^[135]  I wish to thank Tikhon Pino, Antoine Lévy, Mark Spencer, and Marius Portaru for their comments on an earlier draft of this essay. Needless to say, any errors that remain are my own.