St Thomas also sets aside the 'necessary reasons' through which some theologians tried to show that reason is compelled to acknowledge the Trinity. This idea of 'necessary reasons' was brought into play in the eleventh century by Anselm's Monologium. St Anselm chose a method which drew on 'necessary reasons' over one which made direct use of sacred Scripture, and which proposed rational arguments leading to 'quasi-necessary conclusions'; ifi this
13 Summa fratris Alexandri, Book I, no. 10, (ed. Collegii S. Bonaventure, vol. 1, Quaracchi, 1924, p. 19).
14 Albert, I Sent. d. 3, a. 18, sol. (Opera omnia, vol. 25, ed. Auguste Borgnet, Paris, 1893, p. 113).
15 Thomas, ST I, q. 32, a. 1; cf. De veritate, q. 10, a. 13. On the originality of this response, see G. Emery, La Trinité créatrice, Paris, 1995, pp. 345-351.
16 For the references to St Anselm and Richard of St Victor, see our study, 'Trinité et Unite; de Dieu dans la scolastique XIIe-XIVe siecles', pp. 207-213.
enabled him to see in God both Word (the Son) and Love (the Holy Spirit). The track which Anselm had opened up was explored in an original way by Richard of St-Victor, in his De Trinitate (c.1170). At the heart of knowledge by faith, Richard wanted to present 'necessary reasons' supporting the Trinity, that is to say, 'to understand through reason that which we believe'; since the Trinity is not a contingent, but a necessary reality, one can establish it through 'arguments which are not only plausible or probable, but necessary'. Richard wants to show that the plenitude of the goodness of God, God's plenitude of happiness, and of glory, like the plenitude of divine charity, all require that there is in God a plurality of persons amongst whom goodness, happiness, and charity are communicated. This project of demonstrating the Trinity, by an exercise which is simultaneously logical, metaphysical, contemplative, and aesthetic, will exert a lasting fascination in the history of theology.
St Bonaventure (+1274) brought together the legacy of Anselm and Richard of St-Victor with that of Pseudo-Dionysius. Prior to his work, the first Franciscan masters put forward the notion of the Good to account for the plurality of the divine persons: it belongs to goodness to communicate itself (bonum diffusivum sui). Since the divine goodness is perfect, its communication must be perfect, and that requires an alterity of persons within God: the perfect goodness of God implies the communication of the divine substance in God himself by the generation of the Son and the spiration of the Holy Spirit.17 Bonaventure develops this teaching when he elaborates the 'necessary reasons' with the following motifs:
• It is natural for the good to diffuse itself; so if God did not communicate himself through a perfect diffusion of the entirety of the divine substance, he would not be sovereign and perfect Good;
• the beatitude, charity, liberality, and joy of God require that one posit a plurality of persons in God, since their perfection cannot exist in solitary confinement;
• the primacy (primitas) in God entails a plurality of persons, since when one reality is first, it is the principle of another; in virtue of his primacy, one must recognize that God has a sovereign fecundity and 'Sourceness' (fon-talitas), according to the two modes which pertain to God: an emanation of nature (generation of the Son) and an emanation of will (the procession of the Holy Spirit);
• the perfect actuality of God demands that this communication be not only possible but necessary, for in God no state of potentiality exists: God's
17 Alexander of Hales, Summa theologica, Book I, no. 317 (ed. Collegii S. Bonaventurae, vol. 1, Quaracchi, 1924, pp. 465-466).
entire existence is in a state of perfect actuality. 'It is thus necessary to affirm a plurality of persons.'18
Thus, according to Bonaventure, affirmation of the Trinity necessarily follows from balanced consideration of the unity of God: the recognition of the Trinity is 'included' in the affirmation of divine unity, and the reasons he gives enable one to explain this inclusion in a way that imposes itself with the force of necessity. So, for Bonaventure, the believing mind can rise to the contemplation of the Trinity on the basis of the perfection which reason must necessarily recognize in God.
Many other writers embarked on the quest for necessary reasons. So, for instance, Henry of Ghent (+1293) acknowledged that we can only know the Trinity by faith; but at the same time, after faith has given us access to the Trinity, we can 'prove its necessity' by rational argument. Henry held that the perfection of intellectual activity in God necessarily requires the fruitful production of a personal Word; likewise, God's perfect voluntative and loving activity demands the spiration of the Holy Spirit. Reason can prove this. Henry of Ghent concluded that, if God were not Triune, he could not have created the world with wisdom and freedom. The person of the Word (wisdom) and the person of the Spirit (love, freedom), are thus necessarily required to think through the act of creation. 19
St Thomas was vigorously opposed to this apologetic project in Trinitarian theology. Neither the goodness nor the happiness of God, nor his intelligence, are arguments capable of proving that the existence of a plurality of divine persons imposes itself by rational necessity.2° Only the 'truth of faith', to the exclusion of any other reason, leads us to acknowledge God's tripersonality.21 This thesis is a fundamental and characteristic feature of his Trinitarian theology. For Thomas, Bonaventure's reasons could be probable arguments, but they do not have the force of necessity. And, in Thomas' judgement, the attempt to give necessary reasons in Trinitarian theology jeopardizes the faith: 'this undermines the faith'.22 Such a project ignores the dignity of faith— because faith deals with realities that are beyond reason—and it makes the faith liable to ridicule by non-believers, by indicating to them that Christians profess the Trinity on very shaky grounds.23 St Thomas' stance implies
18 Bonaventure, I Sent. d. 2, a. un., q. 2; I Sent. d. 27, p. 1, a. un., q. 2, ad 3; Quaestiones disputatae deMysterio Trinitatis, qq. 1-8; Hexaemeron XI. 11; Itinerarium mentis inDeum, ch. 6.
19 Henri of Ghent, Quodlibet VI, q. 2 (Opera omnia, vol. 10, Leuven and Leiden, 1987, pp. 33-40); cf. q. 1 (pp. 2-31). In a completely different spirit to the medievals, modern philosophers have discussed the Trinity in a more rigorously rationalist vein (see on this, in particular, S. M. Powell, The Trinity in German Thought, Cambridge, 2001).
2° ST I, q. 32, a. 1, ad 2. 21 i Sent. d. 2, q. un., a. 4; cf. ST I, q. 32, a. 1.
a clear-cut divide between the domain of faith and that of natural reason: this straightforward distinction is one of Thomas' most outstanding features, particularly by comparison with Bonaventure. This means that the reasons which theology uses to exhibit the Trinitarian mystery will never be demonstrative proofs. Rather they will be one of two things: either 'approximations' or 'probable arguments'^ that is, arguments which show that what the faith proposes is not impossible, or arguments drawn only from faith.25
In his approach to the Trinity, Thomas' epistemic method is thus characterized by two constant features: First, the strict exclusion of the idea that Trinitarian faith can be established by necessary reasons,26 and second, taking it to be impossible either to conceive the Trinity by deducing it from the divine unity or to think of the plurality of persons as deriving from the essential attributes.27 This second thesis, which is too often neglected, is one of the fundamental features of Thomas' Trinitarian theology. Thomas was a more rigorous thinker than most of his contemporaries, and he wields that rigour in his barring any confusion between our knowledge of the divine essence and our knowledge of personal plurality in God; he strictly refuses to consider God's personal plurality as the fruit of an essential fecundity of the divine being. Hence it is necessary to pin down what we mean by the role of human reason in Trinitarian theology.
Was this article helpful?