1 See for example Rist, J. M., “Basil's ‘Neoplatonism’: Its Background and Nature,” in Fedwick, J. P., ed., Basil of Caesarea: Christian, Humanist, Ascetic , 2 vols. (Toronto, 1981), 1:137–220 and Robertson, D. G., “Stoic and Aristotelian Notions of Substance in Basil of Caesarea,” Vigiliae Christianae 52 (1998): 393-417. I would like to thank John Marenbon, Paul Thom, Margaret Cameron, and Alain de Libera for their remarks on a first draft of this paper. My gratitude also goes to Richard Cross and the anonymous reviewer of Traditio for their very useful comments. This research was carried out during a fellowship of the British Academy.Google Scholar

2 According to Siddals, R., Cyril “shares with the Neo-Platonists of Late Antiquity a genuine fascination for Aristotle's Organon and Porphyry's Isagoge” (“Logic and Christology in Cyril of Alexandria,” Journal of Theological Studies 38 [1987]: 341–67, at 341-42).Google Scholar

3 See Reindl, H., “Der Aristotelismus bei Leontius von Byzanz” (PhD diss., University of Munich, 1953) and Moutafakis, N. J., “Christology and Its Philosophical Complexities in the Thought of Leontius of Byzantium,” History of Philosophy Quarterly 10 (1993): 99-119.Google Scholar

4 For an analysis of the philosophical sources of the Dialectica see Richter, G., Die Dialektik des Johannes von Damaskos: Eine Untersuchung des Textes nach seinen Quellen und seiner Bedeutung (Passau, 1964).Google Scholar

5 On the theological use of Aristotelian logic in the Christian Byzantine context see Roueché, M., “Byzantine Philosophical Texts of the Seventh Century,” Jahrbuch der Österreichischen Byzantinistik 23 (1974): 61–76 and idem, “A Middle Byzantine Handbook of Logic Terminology,” Jahrbuch der Österreichischen Byzantinistik 29 (1980): 71-98.Google Scholar

6 See, for example, Gregory of Nazianzus's Oration on the Great Athanasius 35 (ed. Mossay, J., SC 270 [Paris, 1980], 184-86): “We, in an orthodox sense, say one ousia and three hypostaseis, for the one denotes the nature of the Godhead, the other the properties of the three.” On the history of this formula see Lienhard, J. T., “Ousia and Hypostasis: The Cappadocian Settlement and the Theology of ‘One Hypostasis,’” in Davis, S. T., Kendall, D., and O'Collins, G., eds., The Trinity (Oxford, 2001), 99–122 and de Halleux, A., “Hypostase et personne dans la formation du dogme trinitaire (ca. 375-381),” Revue d'histoire ecclésiastique 79 (1984): 311-69 and 625-70.Google Scholar

7 For a discussion of the formulation of the doctrine of the Trinity in terms of a “substance,” see Alston, W. P., “Substance and the Trinity,” in Davis, S. T. et al., eds., The Trinity , 179–201.Google Scholar

8 Aristotle, Categories 2a11-16.Google Scholar

9 Letter 236 (ed. Courtonne, Y. [Paris, 1966] 3, 53, 1-3): Ούσία δέ καί ύπόστασι,ς ταύτην έχει τήν διαφοράν ήν έχει, το κοινόν προς το καθ' έκαστον, οίον ώς έχει το ζωον προς τον δείνα άνθρωπον.Google Scholar

10 Such an interpretation makes a clear distinction between ousia and hypostasis necessary; the first term refers to what is common to several persons, and the second term to what is said to be proper to an individual. The most important theoretical discussion of this distinction can be found in Gregory of Nyssa's treatise On the Distinction between Essence and Hypostasis (formerly Basil, ep. 38).Google Scholar

11 Theodoret of Cyr, Eranistes (ed. Ettlinger, G. H. [Oxford, 1975], 64, 11–13): Κατά δέ γε την των πατέρων δί,δασκαλίαν, ήν έχει διαφοραν το κοινον προς το 'ίδιον, ή το γένος προς το είδος ή το άτομον, ταύτην ή ούσία προς την ύπόστασιν εχει.Google Scholar

12 See for example Gregory of Nyssa, Ad Simplicium de fide (in Gregorii Nysseni Opera III/1, ed. Müller, F. [Leiden, 1958], 65, 22–24): “As in Adam and in Abel there is only one humanity, so also in the Father and in the Son there is only one Divinity”; ώσπερ έπί του Αδάμ και του Άβελ άνθρωπότης μία, ουτω και επί του πατρός και του υίου θεότης μία.Google Scholar

13 This path of thought is present in several Church Fathers, among whom are some of the most important thinkers of Christian dogma: Basil of Caesarea, Gregory of Nyssa, and Cyril of Alexandria. This led Lebon, J., speaking about the letter On the Distinction between Essence and Hypostasis, which is now attributed to Gregory of Nyssa, to say: “L'homoousie ou unité de ούσία entre les personnes divines se trouve … parfaitement éclairée par l'unité de ούσία qui existe entre les individus humains, c'est-à-dire l'unité générique” (“Le sort du ‘consubtantiel’ nicéen,” Revue d'histoire ecclésiastique 48 [1953]: 632–82, at 633). Notice that the principle of parity is rejected by Gregory of Nazianzus. According to him, the unity of human essence can be conceived only by thought (έπινοία); it is therefore purely conceptual, whereas the unity of divine essence is real. See Oration 31, 15 (ed. Gallay, P., SC 250 [Paris, 1978], 304), where Gregory explains that the human community (κοινότης) possesses a unity that can be conceived only by thought (μόνον έπινοία θεωρετόν).Google Scholar

14 For a discussion of Gregory's position on universals, see González, S., “El realismo platónico de S. Gregorio de Nisa,” Gregorianum 20 (1939): 189–206 and Weiswurm, A., The Nature of Human Knowledge according to Saint Gregory of Nyssa (Washington, 1952), 133-40 (“The Problem of Universals”). See also Cross, R., “Gregory of Nyssa on Universals,” Vigiliae Christianae 56 (2002): 372-410 and Zachhuber, J., “Once Again: Gregory of Nyssa on Universals,” Journal of Theological Studies 56 (2005): 75-98. For an analysis of the influence of Gregory on the Latin theories of universals, through John Scottus Eriugena and his translation of the De hominis opificio , see Erismann, C., “La genèse du réalisme ontologique durant le haut Moyen Âge: Etude doctrinale des théories réalistes de la substance dans le cadre de la réception latine des Catégories d'Aristote et de l'Isagoge de Porphyre (850-1110)” (thesis, Ecole Pratique des Hautes Etudes, University of Lausanne, 2006), to be published by Vrin, Paris. For a different reading of the same topic, see Zachhuber, J., “Das Universalienproblem bei den griechischen Kirchenvätern und im frühen Mittelalter: Vorläufige Überlegungen zu einer wenig erforschten Traditionslinie im ersten Millennium,” Millennium 2 (2005): 137-74.Google Scholar

15 Gregory of Nyssa, Ad Graecos ex communibus notionibus (in Gregorii Nysseni Opera III/1, ed. Müller, , 29, 9–11): πολλας γάρ ύποστάσεις του ενός άνθρωπου καί τρεις υποστάσεις του ένος θεοΰ φαμεν δικαίως.Google Scholar

16 This thesis is what Richard Cross, in a remarkable article, called the “Eastern view” of Trinity (“Two Models of Trinity,” Heythrop Journal 43 [2002]: 275–94). See also idem, “On Generic and Derivation Views of God's Trinitarian Substance,” Scottish Journal of Theology 56 (2003): 464-80.Google Scholar

17 For a detailed history of this term, see Stead, C., “Homoousios (ομοούσιος),” in RAC 16 (Stuttgart, 1991): 364–433.Google Scholar

18 For a presentation of the text of the Symbol of Chalcedon, see Ortiz de Urbina, I., “Das Symbol von Chalkedon: Sein Text, sein Werden, seine dogmatische Bedeutung,” in Grillmeier, A. and Bacht, H., eds., Das Konzil von Chalkedon: Geschichte und Gegenwart , 3 vols. (Würzburg, 1962) 1:389–418.Google Scholar

19 The Council of Chalcedon is only codifying here a tendency among the Fathers to apply the term homoousios to men also. Cyril of Alexandria says that men are said to be “consubstantial” or of the same species (ομοειδείς); see In Ioannis Evangelium 1, 4, 37D (ed. Pusey, P. E. [Oxford, 1868]) and De Trinitate dialogi 1, 407C (ed. Durand, G. M., SC 231 [Paris, 1976], 192). The interpretation of consubstantiality that is given by Cyril goes beyond resemblance and states an identity of substance between individuals of a same species: men are consubstantial because of this identity of substance (της ούσίας ταύτότης) (Thesaurus de sancta et consubtantiali Trinitate 19 [PG 75:313D-316A]). See Boulnois, M.-O., Le paradoxe trinitaire chez Cyrille d'Alexandrie: Herméneutique, analyses philosophiques et argumentation théologique (Paris, 1994), 249–60.Google Scholar

20 The Neoplatonic exegesis of the Isagoge allowed an interesting doctrinal construction to emerge, which gives a synthesis of Platonic and Aristotelian elements. This doctrine defines three states of the universal: (1) The universals before the many (προ τών πολλών): these are Platonic ideas, which will later be interpreted as the models, or ideal paradigms, which subsist in the Demiurge's intellect (or in the mind of God in a Christianized version of the doctrine). (2) The universals in the many (έν τοις πολλοίς): the forms that are immanent to individuals. (3) The universals after the many (έπί τοις πολλοίς): the abstract concepts of immanent forms. This threefold division is sometimes associated with three points of view: the “theological,” the “physical,” and the “logical.” For a formulation of this doctrine, see, among others, Ammonius, In Porphyrii Isagogen , ed. Busse, A., Commentaria in Aristotelem Graeca (= CAG) 4, 3 (Berlin, 1891), 41, 10-20 and Proclus, , In primum Euclidis elementorum librum commentarii , ed. Friedlein, G. (Leipzig, 1873), 50, 16-51, 6.Google Scholar

21 Isagoge , ed. Busse, , 6, 16–23.Google Scholar

22 Ibid., 7, 16–27.Google Scholar

23 A. Benito y Durán has proposed to see Arianism as the result of the application of nominalism to the Trinity, in “El nominalismo arriano y la filosofía cristiana: Eunomio y San Basilio,” Augustinus 5 (1960): 207–26. Tritheism seems a better candidate for this, in that it accepts an essence common to the three persons but denies its extra-mental existence. Arius's position is to present the Father and the Son as different substances.Google Scholar

24 Aristotle, De anima 1, 1, ed. Ross, W. D. (Oxford, 1961), 402b7: το δέ ζώον το καθόλου ήτοι ούθέν έστιν ή ύστερον.Google Scholar

25 In monophysism — a doctrine that recognizes in the incarnate Word only one nature (φύσις) — natures are understood as being particular. Tritheism can be seen as a radical extension of monophysism insofar as it applies to the Trinity the thesis, which originated in Christology, according to which natures are particular. Notice also that monophysism — as opposed to the doctrine of Chalcedon — agrees with the Aristotelian thesis according to which an individual can belong only to one species, in that it attributes only one nature to Christ. However, a monophysite does not necessarily have to be a tritheist, as illustrated by the case of Severus of Antioch.Google Scholar

26 See the articles of A. Van Roey, “La controverse trithéite depuis la condamnation de Conon et Eugène jusqu'à la conversion de l'évêque Elie,” in Delsman, W. C., ed., Von Kanaan bis Kerala: Festschrift für Prof. Mag. Dr. Dr. J. P. M. van der Ploeg (Kevelaer and Neukirchen-Vluyn, 1982), 487–97 and “La controverse trithéite jusqu'à l'excommunication de Conon et Eugène (557-569),” Orientalia Lovaniensia Periodica 16 (1985): 141-65.Google Scholar

27 There are extant commentaries on the Categories (ed. Busse, A., CAG 13, 1), on the Prior Analytics (ed. Wallies, M., CAG 13, 2), on the Posterior Analytics (ed. Wallies, M., CAG 13, 3), on the De anima (ed. Hayduck, M., CAG 15), on the De generatione et corruptione (ed. Vitelli, G., CAG 14, 2), on the Meteorologica (ed. Hayduck, M., CAG 14, 1), and on the Physics (ed. Vitelli, G., CAG 16 and 17).Google Scholar

28 De Aeternitate Mundi contra Proclum , ed. Rabe, H. (Leipzig, 1899).Google Scholar

29 See Saffrey, H.-D., “Le Chrétien Jean Philopon et la survivance de l'école d'Alexandrie au VI^e siècle,” Revue des études grecques 67 (1954): 396–410.Google Scholar

30 On Philoponus's theological thought, see, among others: Booth, E., “John Philoponos: Christian and Aristotelian Conversion,” Studia Patristica 17 (1982): 407–11; Chadwick, H., “Philoponus the Christian Theologian,” in Sorabji, R., ed., Philoponus and the Rejection of Aristotelian Science (London, 1987), 41-56; Hainthaler, T., “Johannes Philoponus, Philosoph und Theologe in Alexandria,” in Grillmeier, A., ed., Jesus der Christus im Glauben der Kirche, 2/4: Die Kirche von Alexandrien mit Nubien und Äthiopien nach 451 (Freiburg, 1990), 109-49; Hermann, T., “Johannes Philoponus als Monophysit,” Zeitschrift für die Neutestamentliche Wissenschaft und die Kunde der älteren Kirche 29 (1930): 209-64.Google Scholar

31 For a remarkable analysis of this text and an English translation, see Lang, U. M., John Philoponus and the Controversies over Chalcedon in the Sixth Century: A Study and Translation of the “Arbiter” (Leuven, 2001).Google Scholar

32 On the problem of Philoponus's tritheism, see the recent article of Lang, U. M., “Patristic Argument and the Use of Philosophy in the Tritheist Controversy of the Sixth Century,” in Twomey, D. V. and Ayres, L., eds., The Mystery of the Holy Trinity in the Fathers of the Church: The Proceedings of the Fourth Patristic Conference, Maynooth, 1999 (Dublin, 2007), 79–99. See also Lang, U. M., “Notes on John Philoponus and the Tritheist Controversy in the Sixth Century,” Oriens Christianus: Hefte für die Kunde des christlichen Orients 85 (2001): 23-40; Martin, H., “Jean Philopon et la controverse trithéite du VI^e siècle,” Studia Patristica 5 (1962): 519-25; and Rashed, M., “Un texte proto-byzantin inédit sur les universaux et la Trinité,” in L'héritage aristotélicien: Textes inédits de l'Antiquité (Paris, 2007), 345-78, at 352-57.Google Scholar

33 I use the Greek text of the critical edition by Kotter, B., Liber de haeresibus (Berlin and New York, 1981).Google Scholar

34 Diekamp, F., Doctrina Patrum de incarnatione Verbi: Ein griechisches Florilegium aus der Wende des 7. und 8. Jahrhundert (Münster, 1907), 272–83.Google Scholar

35 These fragments are collected in van Roey, A., “Les fragments trithéites de Jean Philopon,” Orientalia Lovaniensia Periodica 10 (1980): 135–63.Google Scholar

36 See Ebied, R. Y., van Roey, A., and Wickham, L. R., eds., Peter of Callinicum: Anti-Tritheist Dossier , Orientalia Lovaniensia Analecta 10 (Leuven, 1981).Google Scholar

37 An edition and French translation (in four volumes) of this important chronicle was published by Chabot, J.-B. under the title Chronique de Michel le Syrien, Patriarche Jacobite d'Antioche (1166-1199) (Paris, 1899-1910).Google Scholar

38 Bardy, G., “Jean Philopon,” DThC 8:831–39, at 833 (translation is mine).Google Scholar

39 On the De sectis , see Richard, M., “Le traité de sectis et Léonce de Byzance,” in idem, Opera Minora 2 (Turnhout and Leuven, 1977), n° 55.Google Scholar

40 Actio 5, 6 (PG 86:1232D-1333B).Google Scholar

41 According to Ebied, R. Y., van Roey, A., and Wickham, L. R. ( Peter of Callinicum , 33): “In conclusion it may be said that Tritheism draws its inspiration from a certain philosophical system that it applies to the Trinity. Tritheism is a rationalistic approach that seeks to explain the divine by concepts and principles derived from the created order.” In “Patristic Argument” U. M. Lang has defended an alternative reading in which he emphasizes the importance of the patristic tradition over the philosophical one as the root of Philoponus's tritheism.Google Scholar

42 Van Roey, , “Les fragments trithéites,” 156.Google Scholar

43 Lang, U. M., “Patristic Argument,” 82.Google Scholar

44 This thesis is fundamental to particularism. It can be found in a particularly clear form in a twelfth-century logical compendium inspired by Gilbert of Poitiers: Tot humanitates quot homines. Cf. Compendium logicae porretanum , ed. Ebbesen, S., Fredborg, K. M., and Nielsen, L. O., Cahiers de l'Institut du Moyen Âge grec et latin 46 (Copenhagen, 1983), 41.Google Scholar

45 Richard Cross uses the word nominalism to refer to Philoponus's particularist metaphysics: “his acceptance of particular natures is a direct result of his nominalism, his belief that universals do not have any extra-mental existence,” in “Perichoresis, Deification and Christological Predication in John of Damascus,” Mediaeval Studies 62 (2000): 69–124, at 77.Google Scholar

46 Philoponus, , Arbiter , chap. 7 in John of Damascus, Liber de haeresibus (ed. Kotter, [n. 33 above], 52, 52-55): Αύτη δή ούν ή κοινή φύσις, ή ανθρώπου, καθ' ήν ούδείς άνθρωπος ούδενος διενήνοχεν, έν έκάστω των άτόμων γινομένη ιδία λοιπόν έκείνου και ούδενος ετέρου κοινή γίνεται, καθώς έν τω τετάρτω κεφαλαίω ώρισάμεθα. Το γαρ έν έμοί ζωον λογικον θνητον ούδενος άλλου κοινόν έστιν.Google Scholar

47 Ibid. (52, 66–68): Το γαρ έν έμοί ζωον λογικον θνητον ούδενί των άλλων ανθρώπων έστί κοινόν ουδέ ή έν τωδε τω ΐππω του ζώου φύσις έν άλλω τινί γένοιτ' άν, ώς άρτίως δεδείχαμεν.Google Scholar

48 Ibid. (52, 55–57).Google Scholar

49 A Syriac fragment illustrates this: “Nothing that is called ‘common’ has existence of its own apart from the particular: there exists only this horse, only this man, only this angel” (Contra Themistium, frag. 22, in van Roey, , “Les fragments trithéites” [n. 35 above], 162).Google Scholar

50 Philoponus, , Arbiter (55, 168).Google Scholar

51 In Christological thought after Chalcedon, non-existent (άνυπόστατος), i.e., non-instantiated, universals must be rejected because of the two natures of Christ: it is necessary for the universal man to be entirely present (instantiated) in the individual Christ in order for him to be completely God and completely man.Google Scholar

52 Philoponus, , Arbiter (51, 49–52, 50).Google Scholar

53 Aristotle, De anima (n. 24 above) 1, 1 402b7.Google Scholar

54 Frag. 1; Syriac text in van Roey, , “Les fragments trithéites,” 148.Google Scholar

55 Frag. 2; van Roey, , “Les fragments trithéites,” 148, trans. Lang, U. M., “Patristic Argument,” 95.Google Scholar

56 Contra Themistium, frag. 18a; van Roey, , “Les fragments trithéites,” 154, trans. Ebied, Wickham, and van Roey, , Peter of Callinicum (n. 36 above), 26.Google Scholar

57 Philoponus does not question the consubstantiality of men on the one hand and of the persons of the Trinity on the other. Better even, he grounds it in the plurality of particular substances. According to him, far from compromising consubstantiality, a plurality of substances is a necessary condition for speaking about “consubstantiality” (see frag. 16; van Roey, , “Les fragments trithéites,” 153–54). Consubstantiality is only possible between several substances. Hypostases qua hypostases cannot be consubstantial.Google Scholar

58 In the preface to their edition of the treatise Contra Damianum of Peter of Callinicum (CCG 29 [Turnhout, 1994], xvi) Ebied, Wickham, and van Roey, say: “His teaching [i.e., of Philoponus] on the Trinity develops his interpretation of the Aristotelian distinction between ‘first’ and ‘second’ substance: only first substance, in the fullest sense of the particular, is, for John, actual; second substance, the generic concept, is a creation of the abstracting intellect (‘a posterior fabrication and invention of the mind,’ in a phrase often repeated by Peter of Callinicus). Applied to the doctrine of God in Trinity, this means that each divine hypostasis is equally God (the three are ‘consubstantial’ in this sense) but there is no actual Godhead distinct from the particular Godhead each is. Consequently we may indeed speak of three Gods and three Godheads, three substances and natures; the ‘one’ of the Godhead is in the viewing mind alone.” Google Scholar

59 This position earned Philoponus many criticisms. In his presentation of Philoponus's doctrine, the priest-monk George accused him of having reduced the common substance to a mere mental abstraction with no existence of its own (άνύπαρκτον) apart from the three individual substances (ed. Richard, M., “Le traité de Georges Hiéromoine sur les hérésies,” Revue des études byzantines 28 [1970]: 239–69, at 266, 22-267, 7). The accusation of considering the common essence of the Trinity merely as a rational abstraction, with no other existence than that of the particular substances, can already be found in the testimony of a discussion between a tritheist and Anastasius I, the Chalcedonian Patriarch of Antioch between 559-70 and 593-98. The Ακοινώνητος holds, in his dialogue with the Orthodox, that the common substance (γενική ούσία) of the Trinity can only be contemplated as a concept that is found in particular substances: έν ταΐς μερικαΐς μέν έστι, θεωρείται δε λόγω μόνω. (ed. Uthemann, K. H., “Des Patriarchen Anastasius I. von Antiochien Jerusalemer Streitgespräch mit einem Tritheiten,” Traditio 37 [1981]: 73-108, at 103, 750).Google Scholar

60 Michael the Syrian, Chronicle , ed. Chabot, (n. 37 above) 2, 330–31; 4, 361 = Frag. 29 and 30; van Roey, , “Les fragments trithéites,” 157-58, trans. Lang, U. M., “Patristic Argument” (n. 32 above), 99. See also Ebied, , Wickham, , and van Roey, , Peter of Callinicum, 31-32.Google Scholar

61 I am not questioning in any way — much to the contrary — the excellent analyses given by Constant Mews and Jean Jolivet; I am simply reconsidering the problem from a different angle. See Mews, C., “St Anselm and Roscelin: Some New Texts and their Implications. I. The De incarnatione Verbi and the Disputatio inter Christianum et Gentilem,” Archives d'histoire doctrinale et littéraire du Moyen Âge 58 (1991): 55–98; idem, “Nominalism and Theology before Abaelard: New Light on Roscelin of Compiègne,” Vivarium 30 (1992): 4-34; idem, “St Anselm, Roscelin and the See of Beauvais,” in Luscombe, D. E. and Evans, G. R., eds., Anselm: Aosta, Bec and Canterbury (Sheffield, 1996), 106-19; idem, “The Trinitarian Doctrine of Roscelin of Compiègne and Its Influence: Twefth-Century Nominalism and Theology Re-considered,” in de Libera, A., Elamrani-Jamal, A., and Galonnier, A., eds., Langages et philosophie: hommage à Jean Jolivet (Paris, 1997), 347-64; idem, “St Anselm and Roscelin of Compiègne: Some New Texts and their Implications. II. A Vocalist Essay on the Trinity and Intellectual Debate c. 1080-1120,” Archives d'histoire doctrinale et littéraire du Moyen Âge 65 (1998): 39-90. These articles have all been republished in Mews, C., Reason and Belief in the Age of Roscelin and Abelard (Aldershot, 2002). See also Jolivet, J., “Trois variations médiévales sur l'universel et l'individu: Roscelin, Abélard, Gilbert de la Porrée,” Revue de métaphysique et de morale 97 (1992): 111-55.Google Scholar

62 Anselm, , Letter 128 ( Anselmi Opera omnia , ed. Schmitt, F. S. [Seckau, Rome, and Edinburgh, 1938-61], 3, 270, 8-271, 11): “Hanc enim inde quaestionem Rocelinus de Compendio movet: ‘Si tres personae sunt una tantum res et non sunt tres res per se, sicut tres angeli aut tres animae, ita tamen ut voluntate et potentia omnino sint idem: ergo pater et spiritus sanctus cum filio incarnatus est.’” Google Scholar

63 Anselm, , Letter 129 (ed. Schmitt, , 3, 271, 21-22): “Quod si dicit tres personas esse tres res, secundum quod unaquaeque Deus est: aut tres deos vult constituere, aut non intelligit quod dicit.” Google Scholar

64 Anselm, , Letter 136 (ed. Schmitt, , 3, 279, 3-7): “Audio — quod tamen absque dubietate credere non possum — quia Roscelinus clericus dicit in deo tres personas esse tres res ab invicem separatas, sicut sunt tres angeli, ita tamen ut una sit voluntas et potestas; aut patrem et spiritum sanctum esse incarnatum; et tres deos vere posse dici, si usus admitteret” (Anselm of Canterbury, Complete Philosophical and Theological Treatises , trans. Hopkins, J. and Richardson, H. [Minneapolis, 2000], 263).Google Scholar

65 Epistola de incarnatione Verbi (ed. Schmitt, , 2, 4, 5–9): “Cum adhuc in Becci monasterio abbas essem, praesumpta est a quodam clerico in Francia talis assertio: ‘Si, inquit, in deo tres personae sunt una tantum res et non sunt tres res unaquaeque per se separatim, sicut tres angeli aut tres animae, ita tamen ut voluntate et potentia omnino sint idem: ergo pater et spiritus sanctus cum filio est incarnatus.”’ Google Scholar

66 Note that the example chosen by Roscelin indicates that he is thinking of a distinction of substance and not only of relation.Google Scholar

67 Denying this would amount to accepting Sabellius's heresy.Google Scholar

68 Anselm, , Epistola de incarnatione Verbi , 9, 20–10, 21: “Cum que omnes ut cautissime ad sacrae paginae quaestiones accedant, sint commonendi: illi utique nostri temporis dialectici, immo dialecticae haeretici, qui non nisi flatum vocis putant universales esse substantias, et qui colorem non aliud queunt intelligere quam corpus, nec sapientiam hominis aliud quam animam, prorsus a spiritualium quaestionum disputatione sunt exsufflandi” ( Treatises , trans. Hopkins, and Richardson, , 269).Google Scholar

69 On Roscelin, universals, and ontological particularism, see Gentile, L., Roscellino di Compiègne ed il problema degli universali (Lanciano, 1975); Kluge, E.-H., “Roscelin and the Medieval Problem of Universals,” Journal of the History of Philosophy 14 (1976): 405-14; Reiners, J., Der Nominalismus in der Frühscholastik: Ein Beitrag zur Geschichte der Universalienfrage im Mittelalter, Beiträge zur Geschichte der Philosophie des Mittelalters 8, 5 (Münster, 1910); G. d'Onofrio, “Anselmo e i teologi ‘moderni,’” in Gilbert, P., Kohlenberger, H., and Salmann, E., eds., Cur Deus Homo (Rome, 1999), 87-146.Google Scholar

70 Anselm, , Epistola de incarnatione Verbi , 10, 4–7: “Qui enim nondum intelligit quomodo plures homines in specie sint unus homo: qualiter in illa secretissima et altissima natura comprehendet quomodo plures personae, quarum singula quaeque perfectus est deus, sint unus deus?” (Treatises , trans. Hopkins, and Richardson, , 269-70).Google Scholar

71 Anselm, , Epistola de incarnatione Verbi , 10, 9–13: “Denique qui non potest intelligere aliquid esse hominem nisi individuum, nullatenus intelliget hominem nisi humanam personam. Omnis enim individuus homo est persona. Quomodo ergo iste intelliget hominem assumptum esse a verbo, non personam, id est naturam aliam, non aliam personam assumptam esse?” (Treatises , trans. Hopkins, and Richardson, , 270).Google Scholar

72 Anselm, , Epistola de incarnatione Verbi , 12, 13–15: “Non enim sic sunt pater et filius duae res, ut in his duabus rebus intelligatur eorum substantia, sed eorum relationes.” Google Scholar

73 Ibid., 14, 6.Google Scholar

74 Anselm, , Monologion (ed. Schmitt, , 1, 27, 45, 6-12): “Nempe cum omnis substantia tractetur aut esse universalis, quae pluribus substantiis essentialiter communis est, ut hominem esse commune est singulis hominibus; aut esse individua, quae universalem essentiam communem habet cum aliis, quemadmodum singuli homines commune habent cum singulis, ut homines sint: quomodo aliquis summam naturam in aliarum substantiarum tractatu contineri intelligit, quae nec in plures substantias se dividit, nec cum alia aliqua per essentialem communionem se colligit?” Google Scholar

75 Anselm, , Epistola de incarnatione Verbi 23, 13–16: “Pater ergo et filius secundum substantiam non sunt plures nec alii ab invicem, quia non sunt duae substantiae, nec alia substantia pater, alia filius, sed una et eadem substantia sunt pater et filius.” Google Scholar

76 Abelard, , Theologia “Summi Boni” 2, 75–76 (ed. Buytaert, E. and Mews, C., CCM 13 [Turnhout, 1987], 140).Google Scholar

77 As proved by the example of Philoponus, who was accused of tritheism and wrote several anti-Arian treatises. See van Roey, A., “Fragments antiariens de Jean Philopon,” Orientalia Lovaniensia Periodica 10 (1979): 237–50.Google Scholar

78 Only the second translation respects the Cappadocian distinction between ousia and hypostasis. Translating hypostasis by substance (which is etymologically correct) introduces a possible confusion because ousia can also be translated by substance and not only by essence. Google Scholar

79 See De Trinitate 5, 8, 10 (ed. Mountain, W. J., CCL 50 [Turnhout, 1968], 216, 43-217, 47). However, later on, Augustine explains that this formula is not usual in Latin; see 5, 8, 10-9, 10 (216, 47-217, 3): “Sed quia nostra loquendi consuetudo iam obtinuit ut hoc intellegatur cum dicimus essentiam quod intellegitur cum dicimus substantiam, non audemus dicere unam essentiam, tres substantias, sed unam essentiam uel substantiam. Tres autem personas multi latini ista tractantes et digni auctoritate dixerunt cum alium modum aptiorem non inuenirent quo enuntiarent uerbis quod sine uerbis intellegebant.” Google Scholar

80 Alcuin, , De fide sanctae et individuae Trinitatis 3 (PL 101:57B-C): “Haec vero sancta Trinitas, nil majus est in tribus personis simul nominatis quam in una qualibet persona semel dicta; quia unaquaeque persona plena est substantia in se, non tamen tres substantiae, sed unus Deus, una substantia, una potentia, una essentia, una aeternitas, una magnitudo, una bonitas Pater, et Filius, et Spiritus sanctus”; and 59C: “Quia una substantia est Pater, et Filius, et Spiritus sanctus, non tres substantiae. Proinde unitas substantiae tres Deos prohibet dicere vel credere.” Google Scholar

81 Eriugena, John Scottus, Periphyseon 2, 598C-599A (ed. Jeauneau, J., CCM 162 [Turnhout, 1997], 100, 2411-22): “In summa itaque ac singulari uniuersorum causa ex qua et in qua et sunt et condita sunt totius creaturae principia (hoc est primordiales causae) considerandum arbitror utrum ipsa dum sit unitas et trinitas — diuina siquidem bonitas est una essentia in tribus substantiis et tres substantiae in una essentia, uel secundum usum romanae linguae dicendum, una substantia in tribus personis et tres personae in una substantia — in se ipsa causas quodam modo differentes a se inuicem habeat, hoc est, utrum sicut de ipsa praedicatur una essentia in tribus substantiis, ita etiam una essentialis causa in tribus subsistentibus causis et tres subsistentes causae in una essentiali causa credendum est et intelligendum.” Google Scholar

82 Anselm, , Monologion , 79.Google Scholar

83 See Morin, G., “Un écrivain inconnu du XIe siècle: Walter, moine de Honnecourt, puis de Vézelay,” Revue Bénédictine 22 (1905): 165–80, at 177. Trans. Mews, C., “St Anselm and Roscelin … II” (n. 61 above), 51.Google Scholar

84 Ed. Reiners, , Nominalismus (n. 69 above), 72.Google Scholar

85 See, among other texts, De Trinitate 7, 4, 7 (ed. Mountain, , 255, 1-6): “Itaque loquendi causa de ineffabilibus ut fari aliquo modo possemus quod effari nullo modo possumus dictum est a nostris graecis una essentia, tres substantiae, a latinis autem una essentia uel substantia, tres personae quia sicut iam diximus non aliter in sermone nostro, id est latino, essentia quam substantia solet intellegi.” Google Scholar

86 See de Ghellinck, J., “L'entrée d'essentia, substantia, et autres mots apparentés, dans le latin medieval,” Archivum latinitatis medii aevi 16 (1942): 77–112.Google Scholar

87 Mews, C., “The Trinitarian Doctrine of Roscelin of Compiègne and Its Influence: Twelfth-Century Nominalism and Theology Re-considered,” in de Libera, Elamrani-Jamal, and Galonnier, , eds., Langages et philosophie (n. 61 above), 347–64, at 357.Google Scholar

88 Isidore, , Etymologiae 7, 4, 2–11.Google Scholar

89 Nominalismus , ed. Reiners, , 76, 34.Google Scholar

90 Augustine rejects the use of the plural of essentia to speak about God: “Sic enim quia hoc illi est deum esse quod est esse, tam tres essentias quam tres deos dici fas non est” ( De Trinitate 7, 4, 9 [ed. Mountain, , 259, 139-260, 141]). See also “Sicut ergo non dicimus tres essentias” (De Trinitate 5, 10, 11 [ed. idem, 217, 1]).Google Scholar

91 The entire letter tends to weaken lexical and conceptual distinctions. Roscelin mixes Greek and Latin formulae, quotes many authorities, and seems generally to seek to demonstrate the relativity of language. He even says this: “When therefore we vary these names or proffer them in the singular or in the plural, we do this not because it might signify one thing rather than another, but by virtue only of the will of the speakers to whom such a habit of speech is pleasing” ( Nominalismus , ed. Reiners, , 73, 1–5; trans. Mews, C., “Nominalism and Theology before Abaelard: New Light on Roscelin of Compiègne” [n. 61 above], 9).Google Scholar

92 In the case of Philoponus, this is evidently a consequence of his acceptance of monophysism, which postulates a perfect synonymy of the terms φύσις, ύπόστασις, πρόσωπον. See Hainthaler, T.: “The basic axiom of [Philoponus's] thought lies in his almost total equation of nature and hypostasis” (“John Philoponus, Philosopher and Theologian in Alexandria,” in Grillmeier, A., ed., Christ in Christian Tradition, 2/4: The Church of Alexandria with Nubia and Ethiopia after 451 , trans. Dean, O. C. [Louisville, KY, 1996], 107–46, at 112).Google Scholar

93 It seems appropriate to disagree slightly with René Roques, who sees in Roscelin's letter a perfectly orthodox Trinitarian theology. Indeed, apparently, it is so; Roscelin is not seeking to convert others to his views. Prudently, and maybe by ambition, Roscelin retracted his view. It nonetheless seems that the understanding of essentia as a synonym of persona is a problematic reminder of his prior position. René Roques thought that “ces positions très fermes s'opposent donc de la manière la plus radicale et la plus totale à la doctrine des dicta reprochée à Roscelin vers les années 1090” (Ecole Pratique des Hautes Etudes, Annuaire des cours, V^e Section, années 1971-1973, 389). This opposition is perhaps more in form than in content.Google Scholar

94 This reduction of essentia to persona is diametrically opposed to Cappadocian theology, which is based on the distinction between hypostasis and ousia understood as a common entity.Google Scholar

95 On early medieval realism, see Erismann, C., “Immanent Realism: A Reconstruction of an Early Medieval Solution to the Problem of Universals,” Documenti e studi sulla tradizione filosofica medievale 18 (2007): 211–29; idem, “The Logic of Being: Eriugena's Dialectical Ontology,” Vivarium 45 (2007): 203-18; idem, “Processio id est multiplicatio: L'influence latine de l'ontologie de Porphyre; le cas de Jean Scot Erigène,” Revue des sciences philosophiques et théologiques 88 (2004): 401-60.Google Scholar

96 Anselm is a defender of early medieval realism: an individual is composed of its species and a collection of properties (De grammatico 20 [ed. Schmitt, 166, 2–5]). Each individual possesses properties, the collection of which cannot occur identically in another (De processione spiritus sancti 16 red. Schmitt, 217, 17–18]). Therefore, the collection of properties of Peter cannot be that of Paul (Epistola de incarnatione Verbi 11, 29, 15–16). On this Anselmian doctrine, see C. Erismann, “Collectio proprieiatum: Anselme de Canterbury et le problerne de l'individuation,” Mediaeoalia: Textos e estudos 22 (2003): 55–71. On the problem of individuation see J. J. E. Gracia, Introduction to the Problem of Individuation in the Early Middle Ages (Washington, 1984). Google Scholar