PERSON. — It indicates the dignity of the spiritual nature that subsists: “Persona significat id quod est perfectissimum in tota natura, scilicet subsistens in rationali natura” (Sum. Theol., 1ª, q. 29, a. 3). In Greek, as Boethius recalls, it was the “mask” that actors wore on their faces (προσωπον) when representing stage characters; the Latin term p. “dicta est a personando, quia concavitate ipsa maior necesse est ut volvatur sonus” (Boethius, *De duabus naturis*, cap. 3: PL 64, 1344). The definition of the same Boethius is traditional in Latin theology: “P. est rationalis naturae individua substantia” (PL 64, 1343). Less well known is the other definition recalled by St. Thomas (Sum. Theol., 1ª, q. 29, a. 3 ad 2): “P. est hypostasis proprietate distincta ad dignitatem pertinente,” which is from Alain of Lille ([v.]; cf. *Theologica regulae*, § 32: PL 210, 637). Since hypostasis (v.) is the complete individual nature, p. is the rational hypostasis: “Ideo omne individuum rationalis naturae dicitur persona” (Sum. Theol., 1ª, q. 29, a. 3 ad 2). In the strict metaphysical sense, therefore, from this point of view p. adds to hypostasis only the qualification of the dignity of rational nature and not a new constitutive ontological principle (cf. ibid., ad 1). The concept of p., therefore, in its metaphysical content coincides with that of hypostasis or subsistence (hoc aliquid, 5082: Aristotle, *Met.*, VII, 13, 1038 b 24) and is distinguished from “nature” (v.) both universal and individual, inasmuch as in creatures it is indeed the fundamental constituent of beings, but is not itself subsistent: to subsist, individual nature requires accidents and the act of being.
Thus the human nature in Christ is indeed singular but is not a p. precisely because it is assumed and subsists in the divine p. of the Word; whereas in the mystery of the Most Holy Trinity (v.) the one and identical nature subsists in three divine Persons who are distinguished by the opposition of relations. The heresies that have arisen concerning the dogmas of the Trinity and the Incarnation have their origin in the uncertain determination of the meaning and respective relationships among “nature,” “substance,” “hypostasis,” and p., also because the Greek terms do not always have an adequate correspondence in Latin, as St. Thomas wisely warns (cf. *Contra errores Graecorum*, Proemium).
Only with Christianity, which attributes to man freedom (v.), i.e., the faculty of choosing his ultimate end (v.) and therefore the full responsibility for his actions, does the concept of p. attain its ultimate exigency of “dominion” that spirit has over bodies (Sum. Theol., 1, q. 39, a. 1). In the Greek world, man is subject to the laws of “fate” (εἰμαι μήν) and “necessity” (ἐνάγκη), which even the gods cannot change; the “providence” (πρόνοια) to which the latest Greek philosophy (Stoics, Neoplatonists) resorts does not break the circle of necessity (v.) but merely executes the plan of each one’s destiny (cf. W. Chase Greene, *Moira, Fate, Good and Evil in Greek thought*, Cambridge 1944, pp. 313, 317).
Some among the Neoscholastics have claimed to introduce a radical opposition and distinction between individual (v.) and p., inasmuch as the individual pertains to the material aspect of the single being with its animal and egoistic instincts, while p. expresses the higher life in the relationship that the individual has toward God and society (Maritain, Garrigou-Lagrange, Gillet, Delos). However, on the metaphysical plane the unity of the being must remain firm, and the principle (characteristic of Thomism) that the same spiritual soul, as the substantial form of the body, is the source in man of every act and perfection, not only in the intellectual sphere but also in the sensitive and biological (v. *de anima*, a. 11, c). It is only from a functional, not a strictly ontological, point of view that the human soul transcends the body (v. *de spirit. creat.*, a. 2 ad 2), and in this sense St. Thomas defends, against every form of Platonism (v.), that the perfection of man requires the body, and therefore corporeal individuality has a constitutive and positive value (loc. cit., a. 2, ad 5).
This ontological distinction and opposition between individual and p. finds favor instead with transcendental idealism, especially Hegelian, according to which the “single being” is the immediacy of appearance that must “vanish” or “sublate” itself, through mediation, into the absolute personality of the Idea or Universal Spirit: for Hegel the individual is a “form of evil” (cf. *Grundlinien der Philosophie des Rechts*, § 139: ed. E. Gans, Berlin 1840, p. 179 ff.). The only p., subject of right, is the State. The reaction of existentialism (v.) has the precise intent of reclaiming the notion of p. as spiritual individual, primary subject of freedom, against the idealist nullification: KIERKEGAARD, SOEREN AABYE (v.) in particular the “single being” is the “Christian category par excellence, with which the cause of Christianity stands or falls” (cf. *Diary*, Italian trans., I, Brescia 1948, pp. 343, 392 ff.). The dialectic of p., understood as communication of the “I-Thou” relationship, is also present in Feuerbach’s anti-Hegelian polemic (cf. *Grundsätze der Philosophie der Zukunft*, 62: “Die wahre Dialektik ist kein Monolog... sie ist ein Dialog zwischen Ich und Du”; ed. Bohlin-Jodl, II, Stuttgart 1904, p. 319), but it has been particularly developed in a phenomenological sense by Max Scheler (*Natur und Wesen der Sympathie*, 5th ed., Frankfurt a.M. 1948, especially p. 252 ff.) and in a theological sense by M. Buber (*Ich und Du*, in *Dialogisches Leben*, Zurich 1947, p. 13 ff.). In the Christian social personalism of E. Mounier (v.) p. is characterized by the transcendence it has over its empirical conditions and by the subjectivity that, as a creature, it owes to God as the infinite reality that transcends it (E. Mounier, *Liberté sous conditions*, Paris 1946, p. 66 ff.).
In left or neutral existentialism, the ontological dimension of p. is instead bent toward the generic orientation toward being itself (Sein selbst: Heidegger) or toward encompassing being (Das Umgreifende: Jaspers) or is shattered outright in the antithesis of “subject” and other (en soi and pour soi, autrui: Sartre): in this way existentialism renounces its most consistent metaphysical stance against idealism (cf. F. J. von Rintelen, *Philosophie der Endlichkeit*, Meisenheim-Glan 1951, p. 416).
From the notion of p. depend the meaning and structure of the problems of spiritual life, ethics, and politics, so that this notion is not so much an endpoint of philosophical reflection as the criterion and necessary reference according to which every philosophy tests its validity.