SINGOLARE. - In the metaphysical sense, s. is the subsistent individual, that is, the “first substance” (οὐσία πρώτη, in opposition to the “second substance” (οὐσία δευτέρα), namely, the species and genera of logic (cf. Aristotle, Catt., 5, 2 a 11, and Periherm., 7, 17 a 40); individual (v.) that is incommunicable and expresses the numerically one real being (id., Met., III, 4,999 b 33).
The constitutive principle of the s. (the principle of individuation [v.] in material substances) is, according to s. Tommaso, matter insofar as it is found under real dimensions (“materia corporalis sub determinatis dimensionibus contenta”: Sup. I, II de anima, lect. 12; ed. Pirotta. Torino 1925, no. 377, p. 132 b). In this sense the material s. is directly accessible in itself to the senses, whereas the intellect apprehends the universal: τὸ μὲν γὰρ καθὼλον κατὰ τὸν λόγον γνώριμον, τὸ δὲ καθ' ἕκαστον κατὰ τὴν αἰσθησιν (Aristotle, Phys., I, 5, 189 a 6; cf. Met., V, 11, 1018 b 33): hence the controversy, debated in the Middle Ages against the Arab philosophers (especially Averroes), concerning the possibility that God might know the s. directly, on which the meaning and very reality of divine providence depend (cf. Sum. Theol., 1°, q. 14, a. 11; J. Koch, Giles of Rome, Errores philosophorum, Milwaukee 1944; Errores Averrois, nos. 6, 8 and 9). In the social and religious sense, s. is the single human person who distinguishes himself from the mass or multitude and relates to society and to God according to rights and duties: KIERKEGAARD, SOEREN AABYE (v.) contrasts the Christian principle of personality (the “individual before God”) with Hegelian pantheism.