QUASI-FORMAL CAUSALITY AND ' CHANGE IN THE OTHER': A NOTE ON KARL RAHNER'S CHRISTOLOGY characteristic and prominent of the claims made by Karl Rahner about the incarnation are the following three. (1) Only the Logos, the second Person of the Trinity, and not the Father or the Holy Spirit, can be incarnated.1 (~) Granted there is to be a mission ad extra of the Logos, what comes to be is the hypostatic union of the Logos with some created nature, and indeed, with a human nature and a human nature alone.2 (8) The Logos, immutable in himself because identical with the divine nature, is mutable in the " other" of the human nature which he assmnes hypostatically.3 I am concerned in this article with how these three claims are related to a fourth, more generally theological, claim of Fr. Rah...ner's, namely: (4) The supernatural self-communication of God to what is not God must be understood as a kind of quasi-formal causality exercised by God on the creature.4 1" Current Problems in Christology," Theological Investigations I, trans. Cornelius Ernst (Baltimore: Helicon, 1961), p. 183; "On the Theology of the Incarnation," TI IV, trans. Kevin Smyth (Baltimore: Helicon, 1966), pp. 106, 115; "Nature and Grace," TI IV, p. 176 "The Theology of the Symbol," TI IV, p. 236; The Trilnity, trans. Joseph Donceel (New York: Seabury Press, 1974), pp. 29, 84, 86. 2" Current Problems," p. 197; "Theology of the Incarnation," p. 116; "Theology of the Symbol," pp. 237-238; 'Prinity, pp. 27, 32-33, 89-90. 3" Current Problems," pp. 175-182, esp. p. 181, note 3; "Theology of the Incarnation," pp. 112-115. 4 "Some Implications of the Scholastic Concept of Uncreated Grace," TI I, pp. 329-333, 334ff.; "Nature and Grace," p. 175; Trinity, p. 36. 293 ~94 GUY MANSINI, O.S.B. In Christology, this fourth claim means that the Logos is quasiformally related to the humanity of Jesus. More particularly, just as uncreated grace is qua~si-formally related to the just so that created sanctifying grace is its dispositive formal effect, really distinct from it 5 , and just as the divine essence is quasiformally :related to the created and beatified intellect so that the lumen gloriae is its dispositive formal effect, :really distinct from it 6, so the divine esse of the Logos is quasi-formally related to the humanity of Jesus so that the esse secondarium of Christ spoken of by St. Thomas is its dispositive formal effect, really distinct from it.7 In all three cases, and in Maurice de la Taille's words, some created reality, though not informed by Uncreated Act, is actuated by it. In each case, some created actuation-sanctifying grace, the light of glory, the esse secondariumr -disposes created reality to quasi-formal union with Uncreated Act.8 Indeed, I am assuming the substantial identity of the positions of Fr. Rahner and Fr. de la Taille on the supernatural. This assumption is justified on two grounds, beyond Fr. Rahner's own recognition of the identity of his position with Fr. de la Taille's.9 First, like Fr. de la Taille, Fr. Rahner expressly distinguishes between a form and its actuation.10 Sec5 "Uncreated Grace," p. 341. s fbid., pp. 332-333. 1 Cf. Fr. Rahner's remarks as reported in the "Rapport Patfoort," in Problemes aotuels de ohristologie, edited by H. Bouesse and J.-J. Latour (Paris: Desclee de Brouwer, 1965), pp. 414-415. For St. Thomas, cf. his disputed question De unione Ve1·bi inoai·nati, a. 4. s Cf. Maurice de la, Taille, S.J., The llypostatio Un·imi and Created Aotuation by Uncreated Aot ('West Baden, Indiana: West Baden College, 1952), esp. pp. 30, 32-35. This booklet contains a translation of de la Taille's "Actuation cree par acte incree_," which first appeared in 1928 in Recherches de science religieuse. 9 Rahner, "Uncreated Grace," p. 340. io Ibid., p. 331, note 1: "It is usual today to distinguish two senses of ' forma' by speaking of 'actus informans' and ' actus terminans ': thus, 'forma' (the determination) in the first sense is that which in itself arrives at reality and...