¹ I shall be using the Bruno Decker edition of St. Thomas', Expositio super librum De Trinitate, in Studien und Texte zur Geistesgeschichte des Mittelalters, (Leiden: E.J. Brill, 1955)Google Scholar. Hereafter I shall abbreviate this to In Boet. I will utilize the standard abbreviations for all of St. Thomas' other writings. All references to Boethius' Theological Tractates and Consolation of Philosophy will be taken from the edition of Stewart, H.F., Rand, E.K., and Tester, S.J., (Cambridge, 1973), Loeb Classical Library Series, volume 74Google Scholar. All references to Boethius' commentary on Porphyry will be taken from the edition of Schepss, G. and Brandt, S., In Isagogen Porphyrii Commenta, in Corpus Scriptorum Ecclesiasticorum Latinorum (CSEL), 48 (Wien, 1906)Google Scholar. All other Boethian references will be made from writings contained in the Opera Omnia edition of Migne, in Patrologie Cursus Completus, Series Latina (PL), vol. 63/537–64/1628, (Paris, 1882–91)Google Scholar.

² This statement by Boethius can be found in De Trin., I, pp. 6–7 (page references are to the Latin-English text in the Loeb edition). Boethius' doctrine of individuation may be seen in the following texts: “Sed numero differentiam accidentium varietas facit. Nam tres neque genere neque specie sed suis accidentibus distant…” De Trin., I, pp. 6–7Google Scholar; “Atque ideo sunt numero plures, quoniam accidentibus plures fiunt.” Ibid., I, pp. 6–7; “Ea vero quae individua sunt et solo numero discrepunt, solis accidentibus distant.” In Isag., p. 241 ; “…quocumque enim Socrates a Platone distiterit — nullo autem alio distare nisi accidentibus potest-…” Ibid., p. 271 ; “Individua ergo dicuntur huiusmodi, quoniam ex proprietatibus consistit unumquodque eorum, quarum collectio numquam in alio eadem erit.” Ibid., p. 234. For Boethius, the ultimate individuator is the accident of place: “…nam vel si animo cuncta ab his accidentia separemus, tamen locus cunctis diversus est quern unum fingere nullo modo possumus; duo enim corpora unum locum non obtinebunt, qui est accidens.” De Trin., I, pp. 6–9Google Scholar. The statement that “…place is peculiar to each individual” may be found in Atistotle, Met., XIV, 5, 1092a 19–20.

³ In Boet., 4, 1, p. 132.

⁴ Although St. Thomas was personally acquainted with very few Platonic texts, it seems that he was sensitive to certain Platonic overtones contained in the text of Boethius. We can recall that, for Plato, otherness is an idea or form in which all others forms must participate so that they can preserve their selfidentity and be ‘other’ (τρ ετερον, θατερον) from the other forms. In this sense, otherness can be a cause of plurality, cf. Sophist, 255e; 256a–b; 259a–b; Timaeus 36c and 43d; and Parmenides 164–66. The Platonism of Boethius is readily apparent throughout his magum opus, The Consolation of Philosophy, see pp. 146–47; 170–71; 220–21; 234–35; 269–70; 294–95; 306–07 and 410–11. The Theological Tractates also exhibits much Platonism, especially the De Hebdomadibus. Also one may consult Courcelle, P., La Consolation de Philosophie dans la tradition littéraire, (Paris, 1967)Google Scholar.

⁵ cf. “Some of St. Thomas' commentaries contain next to no exposition of the text; the exposition is limited to a very brief sort of paraphrase, which could almost be omitted without substantially altering the work. The text he is commenting on in those instances serves merely as an occasion for his own questions and discussions and replies, which form the main bulk of the work. This is one type of commentary, one that is very free of the limitations of the text being commented upon. Such for example are Scriptum super IV libros Sententiarum and his In librum Boetii de Trinitate.” O'Reilly, Peter, Expositio super librum Boetii De Hebdomadinus: An Edition and a Study, Unpublished Doctoral Dissertation, (University of Toronto, 1960), p. 260Google Scholar.

⁶ “…plurale dicitur aliquid ex hoc quod est divisibile vel divisum. Unde omne illud quod est causa divisionis oportet ponere causam pluralitatis.” In Boet., 4, 1, p. 134Google Scholar.

⁷ “Causa autem divisionis aliter est accipienda in posterioribus et compositis et in primis et simplicibus. In posterioribus namque et compositis causa divisionis quasi formalis, id est ratione cuius fit divisio, est diversitas simplicium et priorum.” In Boet., 4, 1, p. 134.

⁸ In Boel., 4, 1, p. 134.

⁹ “Differens, enim, ut in X Metaphysics determinatur, dicitur ad aliquid, nam omne differens aliquo est differens: diversum autem aliquid absolute dicitur, ex hoc quod non est idem. Differentia igitur in his quaerunda est quae in aliquo conveniunt: oportet enim aliquid in eis assignari secundum quod differant; sicut duae species conveniunt in genere, unde oportet quod differentiis distinguantur. In his autem quae in nullo conveniunt, non est quaerundum quo differant, sed seipsis diversa sunt.” SCG I, 17, #7. St. Thomas draws the same distinction in the following texts — De Potentia 7, 3, ad2; ST I, 3, 8, ad3; I, 90, 1, ad3; In V Met., lect. 12, #913–935 and In X Met., lect. 4, #2013–2022. Also, see Aristotle, Met., X, 3, 1054b22–27; V, 9, 1018a10–14.

¹⁰ “Sed diversitas, qua dividuntur posteriora composita secundum priora et simplicia, praesupponit pluralitatem priorum simplicium. Ex hoc enim homo et asinus habent diversas differentias, quod rationale et irrationale non sunt una, sed plures differentiae. Nee potest semper dici quod illius pluralitatis sit aliqua diversitas aliquorum priorum et simpliciorum causa, quia sic esset abire in infinitum. Et ideo pluralitatis vel divisionis primorum et simplicium oportet alio modo causam assignare.” In Boet., 4, 1, pp. 134–35.

¹¹ “Sunt enim huiusmodi secundum se ipsa divisa. Non potest autem hoc esse, quod ens dividatur ab ente in quantum est ens; nihil autem dividitur ab ente nisi non ens. Unde et ab hoc ente non dividitur hoc ens nisi per hoc quod in hoc ente includitur negatio illius entis.” In Boet., 4, 1, p. 135.

¹² cf. “Unde in primis terminis propositiones negativae sunt immediatae, quasi negatio unius sit in intellectu alterius.” In Boet., 4, 1, p. 135. Also, see De Ver., 2, 15; In IV Met. lect. 6 #605 and ST I–II, 94, 2 (Latin text in note 20).

¹³ “Unde sicut post ens, in quantum est indivisum, statim invenitur unum, ita post divisionem entis et non entis statim invenitur pluralitas priorum simplicium. Hanc autem pluralitatem consequitur ratio diversitatis, secundum quod manet in ea suae causae virtus, scilicet oppositionis entis et non entis.” In Boet., 4, 1, pp. 135–36.

¹⁴ cf. “… secundum esse differt ab aliis.” SCG 1, 25; “…differunt autem secundum esse. Non enim idem est esse homines et esse equi, nee huius hominis et illius hominis.” ST 1, 3, 5; “Item, plura individua sub una specie contenta differunt secundum esse, et tamen conveniunt in una essentia.” Comp. Theol., c. xiv; “Et per hunc modum, hoc esse ab illo esse distinguitur, in quantum est talis vel talis naturae.” De Pot., 7, 2, ad9; “…quia esse uniuscuiusque est ei proprium, et distinctum ab esse cuiuslibet alterius rei; sed ratio substantiae potest esse communis.” De Pot., 7, 3; “Esse autem, inquantum est esse, non potest esse diversum: potest autem diversificari per aliquid quod est praeter esse; sicut esse lapidis est aliud ab esse hominis.” SCG II, 52; Also see De Ver., 2, 11 ; De Ente, c. 5 and De Pot., 7, 2, ad5.

¹⁵ cf. “Omnis enim nobilitas cuiusque rei est sibi secundum suum esse: nulla enim nobilitas esset homini ex sua sapientia nisi per earn sapiens esset, et sic de aliis. Sic ergo secundum modum quo res habet esse, est suus modus in nobilitate: nam res secundum quod suum esse contrahitur ad aliquem specialem modum nobilitatis maiorem vel minorum, dicitur esse secundum hoc nobilior vel minus nobilis. Igitur si aliquid est cui competit tota virtus essendi, ei nulla nobilitatem deesse potest quae alicui rei conveniat. Sed rei quae est suum esse, competit esse secundum totam essendi potestatem…” SCG I, 28, #2. Also see SCG I, 20, #21; I, 28, #4; II, 83,#2 and E. Gilson, “Virtus Essendi”, Mediaeval Studies, 26(1964), pp. 1–11.

¹⁶ Properly speaking, we participate in the esse of God, see De Ver., 2, 3, ad16; In Boet. De Heb., lect. 2; ST I, 3, 4; De Sub Sep., VIII, 43; SCG II, 52, #8 and I, 28.

¹⁷ De Ver., I, 1. cf. “Ens… quod significat ipsum esse.” SCG I, 25, #5; “Unumquodque entium entium habet proprium esse secundum modum suae naturae.” SCG III, 107, #5; “Ens autem non dicit quidditatem, sed solum actum essendi, cum sit principium ipsum.” In I Sent., 8, 4, 2, ad2 (Mandonnet, vol. 1, p. 223); “…nomen autem entis ab actu essendi sumitur…” De Ver., 1, 1, sed contra 3; Also, see In I Sent., 25, 1, 4 (Mandonnet, vol. 1, p. 612); In I Sent., 8, 1, 1, (vol. 1, p. 195); In I Sent., 19, 5, 1 (vol. 1. p. 486); Quod., IX, 2, 2 and XII, 1, 1, adl; In XII Met., lect. 1, #2419 and In IV Met., lect. 1, #553 and 558.

¹⁸ St. Thomas repeatedly emphasizes the fact that it is esse which is innermost in a being, cf. ST I, 4, 1, ad3; I, 7, 1 ; 1, 8, 1; I, 45, 4; In I Sent., 19, 5, 1, ad; In II Sent., I, 1, 1; I, I, 4; SCG II, 54, #5–6; De Pot., 7, 2, ad9; Quod., XII, 6; Q. De Anima I, ad17; 19; In XII Met., lect. 1, #2419. For St. Thomas, only individuals are properly said to exist, cf. De Ente., c. 3 and Q. De Anima I, ad2.

¹⁹ St. Thomas maintains that a thing is knowable only to the extent that it is actually “…unumquodque enim sic cognoscibile est, secundum quod est ens actu.” ST I, 12, 7.

²⁰ cf. “…illud autem quod primo intellectus concipit quasi notissimum et in quod conceptiones omnes resolvit est ens…” De Ver., I, 1; Also, “Nam illud quod primo cadit in apprehensione est ens, cuius intellectus includitur in omnibus quaecumque quis apprehendit. Et ideo primum principium indemonstrabile est quod non est simul affirmare et negare, quod fundatur supra rationem entis et non entis…” ST I-II, 94, 2. cf. In I Met., lect. 1, #46; In I Sent., 19, 5, 1, ad2 and ad ult.; 8, 1, 3; 38, 1, 4, ad4; ST I, 5, 2; 1, 16, 4, ad2; I–II, 55, 4, adl; De Ente Prol.; In Lib. De Causis, lect. 6 (Saffrey, p. 47); De Pot., 9, 7, ad6 and ad 16; De Ver., 21, 1 and 21, 4, ad4. All that we know is knowledge of being (ens) or of some mode of being; all knowledge is an explicitation of this notion of being. Although being is the proper object for intellects, it is most proper to say that material and sensible being is the first, best, and most proper object which the intellect knows. (ST I, 87, 3, ad1).

²¹ De Ver., 1, 3.

²² “Divisio autem quae praesupponitur ad rationem unius, secundum quod convertitur cum ente… est divisio quam causat contradictio, prout hoc ens et illud, dicuntur divisa, ex eo quod hoc non est illud.” In X Met., lect. 4, # 1997. See texts in note 12.

²³ cf. In Boet., 5, 3, p. 183; De Ver., 10, 11, ad 8; In I Periherm., lect. 3, #9; In IX Met., lect. 11, #1900: In I Sent., 38, 1, 3 and ad2 (vol. 1, pp. 903–04); In I Sent.. 8, 1, 3 (vol. 1, p. 200) and In I Sent., 19, 5, 1 ad7 (vol. 1, p. 489). The problematics and ramifications of the Thomistic notion of ‘judgement’ are much too complex to be dealt with here. The finest studies on this notion may be found in: Gilson, Etienne, Being and Some Philosophers, 2nd ed., (Toronto, 1952), ch. VIGoogle Scholar; Owens, Joseph, “Judgment and Truth in St. Thomas Aquinas”, Mediaeval Studies, 32 (1970), pp. 138–58CrossRefGoogle Scholar and “Aquinas on Knowing Existence”, Review of Metaphysics, 29 (1976), pp. 670–90Google Scholar.

²⁴ cf. De Ver., I, 1, ad1; ad3; I, 3 :ST I, 16, 2. In De Veritate I, 1, St. Thomas quotes the Aristotelian definition of truth : “…cum dicitur esse quod est aut non esse quod non est.” See Aristotle, Met., IV, 7, 1011b25–30. Truth is, properly speaking, found in the judging intellect but our truth does follow upon the esse of things. See Phelan, G., “Verum Sequitur Esse Rerum”, Mediaeval Studies, 1 (1939), pp. 11–22CrossRefGoogle Scholar; Owens, Joseph, “Unity and Essence in St. Thoams Aquinas”, Mediaeval Studies, 23 (1961), pp. 248–58CrossRefGoogle Scholar and Schmidt, Robert, The Domain of Logic According to St. Thomas, (Hague, 1966), pp. 202–41Google Scholar.

²⁵ cf. “Sic ergo primo in intellectu nostro cadit ens, et deinde divisio; et post hoc unum quod divisionem privat, et ultimo multitudo quae ex unitatibus constituitur. Nam licet ea quae sunt divisa, multa sint, non habent tamen rationem multorum, nisi postquam huic et illi attribuitur quod sit unum.” In X Met., lect. 4, #1998. Also, see De Pot., 9, 7, ad15 ; De Ver., I, I; In IV Met., lect. 3, #566 and In X Met., lect. 4, #1990–1991. An apparent problem arises here, namely, how can plurality be prior in intelligibility to unity, since plurality seems to involve a notion of unity in that a plurality consists of a number of units? Is this circular reasoning? No, St. Thomas answers that many things are more easily perceived than one thing (not because of their nature). The reason lay in the nature of our sense perceptions (cf. In X Met., lect. 4, #1991). St. Thomas adds: “…nihil prohibit aliquid esse prius et posterius eodem secundum rationem, secundum diversa in eo considerata. In multitudine enim considerari potest, et quod multitudo est, et ipsa divisio. Ratione igitur divisionis prior est quam unum secundum rationem. Nam unum est quod non dividitur. Secundum autem quod est multitudo, posterius est uno secundum rationem, cum multitudo dicatur aggregatio unitatem.” In X Met., lect. 4, #1996.

²⁶ cf. “Ratio enim multitudinis consistit in hoc quod est esse divisa abvincem, aut divisibilia.” In X Met., lect. 4, #1984; “Ratio vero unius consistit in hoc, quod est esse indivisibile, aut non esse divisum.” Ibid., #1985; “…unum non significat privationem puram… sed ipsum ens indivisum.” Ibid., #1998; “…negatio autem consequens omne ens absolute est indivisio, et hanc exprimit hoc nomen unum: nihil aliud enim est unum quam ens indivisum.” De Ver., I, 1.

²⁷ ST I, 76, 4, ad4. cf. In X Met., lect. 4, #2007.

²⁸ cf. In X Met., lect. 4, #1999, 2002, 2007 and In V Met., lect. 17, #1022.

²⁹ Judgements bearing on the self-identity or actual existence of an entity are validated by a direct appeal to sense-experience, cf. “Judicium non dependet tantum a receptione speciei sed ex hoc quod ea de quibus judicatur, examinatur ad aliquod principium cognitionis sicut de conclusionibus judicamus eas in principia resolvendo. Sed quia primum principium nostrae cognitionis est sensus oportet ad sensum quodommodo resolvere omnia de quibus judicamus.” De Ver., 12, 3, ad2. Also see De Ver., I, 11 and the remainder of 12, 3, ad2.

³⁰ cf. “Uno modo secundum divisionem unius ab altero et hoc exprimit hoc nomen aliquid: dicitur enim aliquid quasi aliud quid, unde sicut ens dicitur unum in quantum est indivisum in se ita dicitur aliquid in quantum est ab aliis divisum.” De Ver., I, 1.

³¹ cf. note 23.

³² “Ad quintum dicendum quod Boethius accepit alteritatem pro diversitate, quae constituitur ex aliquibus differentiis, sive sint accidentales sive substantiales. Illa vero, quae sunt diversa et nondifferentia, sunt prima, de quibus hic Boethius non loquitur.” In Boet., 4, 1, ad5, p. 137. cf. 4, 1, p. 136.

³³ “Ad primum ergo dicendum quod numerus ex verbis illis ostenditur esse prior rebus aliis creatis, ut elementis et aliis huiusmodi, non autem aliis intentionibus, ut pote affirmatione et negatione aut divisione vel aliis huiusmodi. Nee tamen quilibet numerus est prior omnibus rebus creatis, sed numerus qui est exemplar omnis rei, scilicet ipse deus, qui secundum Augustinium est numerus omni rei speciem praebens.” In Boet., 4, 1, ad 1, p. 136.

³⁴ St. Thomas indicates that the principle of individuation canont be a mere collection of accidents in In VII Met., Lect. 15, # 1626; In V Met., lect. 8, #876; In II De Anima lect. 12, #377–378 and In III De Anima lect. 8, #711–713. Boethius elaborates on his conception of place in his In Categorias Aristotelis, Book II, PL, 201D–207A. cf. Texts in note 2.

³⁵ cf. “Unde sicut diversitatem in genere vel specie facit diversitas materiae vel formae absolute, ita diversitatem in numero facit haec forma et haec materia.” In Boet., 4, 2, p. 142.

³⁶ cf. “Non enim forma individuator per hoc quod recipitur in materia, nisi quatenus recipitur in hac materia distincta et determinata ad hie et nunc.” In Boet., 4, 2, p. 143.

³⁷ The term ‘signate’, or that which can be designated or pointed to, comes from Avicenna. cf. Roland-Gosselin, M.D., Le “De Ente et Essentia” de S. Thomas d'Aqnin, Bibliotheque Thomiste, VIII, (Le Saulchoir, Kain, Belgium, 1926) pp. 59–66Google Scholar.

³⁸ ST 1, 75, 4; Other important passages are — De Ver., 2, 5; 2, 6 ad1; 8, 11; 10, 5; 10, 4, ad6; 19, 2; 28, 8; SCG 1, 21, # 4; I, 42; I, 65, # 3; II, 49, # 4; II, 50, # 2–4; IV, 81, #7; II, 75, 93, 100; ST I, 3, 2, ad3; I, 3, 3; I, 12, 4; I, 14, 11, ad1; I, 29, 2, ad3; I, 44, 3, ad2; 1, 50, 2; I, 75, 5; I, 76, 2, ad3; ad4; I, 85, 1; I, 86, 1; I, 115, 1; I, 119, 1; I, 101, 1, ad1; III, 77, 2; In Boet., 5, 2; 5, 2, ad1 and 5, 3, ad3. St. Thomas does teach that accidental differences are part of otherness: “… sed diversitas secundum numerum partim in diversitatem materiae, partim in diversitatem accidentis.” In Boet., 4, 2, p. 140; “Alia vero accidentia non sunt principium individuationis, sed sunt principium cogniscendi distinctionem individuorum. Et per hunc modum etiam aliis accidentibus individuatio attribuitur.” In Boet., 4, 2, p. 144. cf. St III, 2, 3, ad 1 and In Boet., 4, 1, obj. 5, p. 133. It should be noted that St. Thomas changed his mind on this point of individuation; St. Thomas fluctuated between determined dimensions as the principle of individuation and indeterminate dimensions. See In Boet., 4, 2, ad3; 4, 2, ad4 and 4, 4. For a look at the historical background behind these two positions, see Roland-Gosselin op. cit., pp. 59–66 (Avicenna); pp. 67–70 (Averroes); and pp. 104–26 (St. Thomas). St. Thomas ended his literary career by agreeing with the Avicennian notion of determined dimensions as the principle of individuation.

³⁹ “Ad secundum dicendum quod dimensiones, cum sint accidentia, per se non possunt esse principium unitatis individuae substantiae; sed materia, prout talibus dimensionibus subest, intelligitur esse principium talis unitatis et multitudines.” In Boet., 4, 2, ad2 p. 144.

⁴⁰ “…sicut tempus est mensura motus, ita locus est mensura corporis.” In Boet., 4, 4, p. 155.

⁴¹ In Boet., 4, 3, p. 149. cf. 4, 3, ad7, p. 153.

⁴² “Secundum hoc enim corpus est in loco, quod loco se commetitur; hoc autem est, secundum quod est dimensionatum dimensionibus aequalibus et similibus dimensionibus loci.” In Boet., 4, 3, p. 149.

⁴³ The natural principles of a composite demand that it fill its own place; in this way, it is divided from all others and indivisible in itself: “Et ideo accipienda est via Avicennae, qua utitur in sua Sufficientia in tractatu De loco, per quam assignat causam prohibitionis praedictae ex ipsa natura corporeitatis per principia naturalia. Dicit enim quod non potest esse causa huius prohibitionis nisi illud cui primo et per se competit esse in loco; hoc est enim quod natum est replere locum.” In Boet., 4, 3, p. 150. Indivisibility is an essential part of being an individual: “…quod de ratione individui est quod sit in se indivisum et ab aliis ultima divisione divisum.” In Boet., 4, 2, ad3, p. 144; “Individuum autem est quod est in se indistinctum, ab aliis vero distinctum.” ST I, 29, 4; “Particularia vero dicuntur individua, in quantum nee materialiter nec formaliter ulterius dividuntur.” In X Met., lect. 10, #2123.

⁴⁴ In Boet., 4, 4, p. 155.

⁴⁵ cf. “Ipsa etiam materia, secundum quod sub dimensionibus existit, prohibet duo corpora esse in eodem loco, in quantum oportet duorum corporum distinctas secundum situm esse materias.” In Boet., 4, 4, p. 155.

⁴⁶ cf. “Et sic patet quod ex eodem causatur diversitas secundum numerum, ex quo causatur necessitas diversitatis locorum in diversis corporibus. Et ideo ipsa diversitas locorum in se considerata est signum diversitatis secundum numerum…” In Boet., 4, 4, p. 155. Also see ad contra 2, p. 156.

⁴⁷ cf. “… quia scilicet nullum aliud accidentium, quae exterius apparent in re completa, est ita propinquum ad causam diversitatis secundum numerum sicut diversitas locorum.” In Boet., 4, 4, pp. 155–56.

⁴⁸ St. Thomas adamantly maintains that matter and form do not exist without one another in this world. Matter can only be known through form because a thing is knowable only insofar as it is in act. (cf. In VII Met., lect. 10, #1496) Prime matter is wholly without act and, thus, is wholly unknowable, cf. In Boet., 4, 3, p. 150; 4, 2, p. 140; In VII Met., lect. 2, #1285 and In VIII Met., lect. 1, #1687. The idea, of course, has its origin in Aristotle, Physics, I, 7, 191a7–12. St. Thomas clearly states that matter is not the first cause of the distinction of things in SCG II, 40, #2.

⁴⁹ cf. Comp. Theol., cc. 71–72; De Pot., III, 16 and ST I, 47, 1.

⁵⁰ Without esse, essence is nothing, cf. De Pot., 7, 2, ad9; SCG II, 53–54 and In VIII Phys., lect. 21.

⁵¹ cf. Comp. Theol., cc. 71–72; De Pot., 7, 2, ad9 and ST I, 76, 6, and ad2. Also, see Aristotle, Met., IV, 2, 1003b31: “…unity is nothing apart from being.” cf. Met., X, 2, 1054a14–15. Aristotle and St. Thomas teach that unity and being are convertible terms. See De Ver., I, 1; Met., IV, 2, 1003b22; VII, 16, 1040b16–28 and VIII, 6, 1045b6. This type of thinking is totally antithetical to Boethian doctrine that there is a metaphysical priority of unity over being. See Boethius, In Isag., p. 162 and De Consol. Phil., III, prose passage 11, pp. 288–89 and 294–95. One cannot read Boethius without being immediately impressed by the strong Neo-Platonic strains running through his works.

⁵² cf. Dimensions by themselves cannot fill a place; In Boet., 4, 3, ad7; Q. De An., 9; 9, ad17 and De Ver., 2, 6, ad 1. St. Thomas was misunderstood on this point by many later thinkers. Because accidents are posterior to substance, they cannot function as the true principles of individuation. Duns Scotus eliminated matter and quantity as possible principles of individuation and criticized St. Thomas for holding such a doctrine, cf. Opus Oxon?, II, d. 3, q. 4–5, vol. 12, pp. 91–127 (All references are to the Paris, Vives, Opera Omnia edition of 1891–1895). Scotus gives his positive doctrine of individuation in Opus Oxon., II, d. 3. q. 6, n. 15. vol. 12, p. 144 and Rep. Paris., II, d. 12, q. 8, n. 8, vol. 23, p. 39. Later, Francis Suarez also repudiated the Thomistic answer and maintained that a thing is numerically one because of its form. cf. Disputationes Metaphysicae, (Paris, Vives, 1856–1878), V, 6, 15, vol. 25, p. 186. It was very easy to misunderstand St. Thomas on this point because he never treats the whole problem of individuation in one place. This problem did not become of major concern until after the time of Aquinas; later thinkers would devote entire treatises to its solution. The Thomistic answer must be searched very carefully and then be artificially reconstructed.

⁵³ Q. De An., 1, ad2. cf. Gilson, E., The Christian Philosophy of St. Thomas Aquinas, (New York, 1956), p. 470, note 10Google Scholar.

⁵⁴ See my comments on Boethius' Platonism in notes 4 and 51.