ASTRATTO, ASTRAZIONE. — 1. In general, “a.” is the designation of mental contents, ideas or universal concepts (v.), in opposition to things existing in themselves in reality, or “concrete” things. Within the same ideal sphere, the reflected or logical universal (animalitas, humanitas... = genus and species...) may be called “a.” in contrast to the direct and metaphysical universal (animal, homo), insofar as the former expresses the mode in which a nature belongs and is predicated, while the latter expresses the real content of that nature according to the mode of being it has in reality. Finally, within the real sphere, “a.” designates substances that are entirely free from commerce with matter, such as God and pure spirits: a notion already present in Plato and Aristotle and which achieved particular diffusion in Neoplatonic metaphysics (the transcendence of the One and the Good).
In Hegel, by contrast, “a.” is the individual as such, which is the subject of perception (“this, here, now”), insofar as it is considered in itself, outside the dialectical movement, and hence unreal; whereas “concrete” designates self-consciousness in that ultimate and complete form which is spirit, the absolute creative freedom of itself and of its modes, corresponding to the categories (Hegel, Vorlesungen über die Geschichte der Philosophie, Leiden 1908, Italian trans., I, Florence 1930, pp. 34 ff.).
actualism (v.), the concrete, which is spirit, is conceived as the indefinite movement of an act never completed that is always being made and becoming: there is neither pure thesis nor pure antithesis, as Hegel maintained; there is neither being nor non-being, but synthesis, that single act which we are, thought (G. Gentile, La riforma della dialettica hegeliana, 2nd ed., Messina 1923, p. 207). existentialism (v.), the concrete once again becomes the individual, the existing person, and a. the object thought.
2. For Plato, the Ideas, or universal forms and species that subsisted in themselves, “separate” from the material substances of which they were the exemplars, were also “real entities.” Plato explained the existence of particulars by means of a “participation” in the Idea, and, correlatively, the valid knowledge that the soul seeks in science by means of a direct “participation” in those subsisting intelligibles. For Aristotle, by contrast, natural substances imply matter as well as form as their constitutive principle; they are “synols” of matter and form, in which form can be understood only as the act and first perfection of a matter, since it can exist only in it: the definition must therefore refer both to matter and to form (Metaph., VI, 1, 1025 b, 31–1026 a, 5; V. ibid., VIII, 5, 1030 b, 14 ff.; De Anima, III, 4, 429 b, 10 ff.). This situation had two consequences: a) essence and form, insofar as it is united to matter, is not intelligible in itself, but manifests itself only through sensible qualities; b) the human soul, the substantial form of the body, is pure potency in the order of knowing: it therefore does not contain intelligibles innately, nor does it “participate” directly in them. Just as essences are potentially intelligible in sensible qualities, so the soul can unite itself with them in knowledge by proceeding from sensible manifestations: the process that effects this passage from the concrete sensible to the intelligible a. is called “abstraction.”
Every passage from potency to act requires a principle in act capable of moving the principle that is in potency to act. There must therefore be two principles of understanding in the soul: one active (the agent intellect), the productive principle of the intelligible from the sensible; the other passive
(the possible intellect), receptive of the intelligible a. (De Anima, III, 5, 430 a, 10 ff.; Sum. Theol., 1ª, q. 79, a. 1–4). The entire process of abstraction takes place in three stages: 1) the preparation of “phantasms,” or sensory representations, by the external and internal senses, particularly the cogitative power (v.) and memory (v. C. Gent., II, 60); 2) the production, by the agent intellect, of the intelligible form (“impressed species”) from the sensible forms of the phantasms, whereby the possible intellect is actualized; 3) the assimilation by the latter of the essence thus abstracted and presented in the intelligible species, and the production—at a second moment—of an immanent term of intellection, which is the “verbum,” or inner word (species or intentio intellecta; C. Gent., I, 53; IV, 11). The stage in which abstraction properly takes place is the second, since it is there that the transition from sensible contents to intelligible contents is effected. S. Tommaso explains the possibility of this transition, subjectively, by the fact that both sense and intellect belong to the same soul and derive from it in relations of mutual dependence (Sum. Theol., 1ª, q. 77, entire); objectively, by the complementarity between the nature of the soul and the content of the phantasm: “Anima intellectiva est quidem actu immaterialis sed est in potentia ad determinatas species rerum. Phantasmata autem e converso sunt quidem actu similitudines specierum quarundam, sed sunt potentia immateriales. Unde nihil prohibet unam et eandem animam, in quantum est immaterialis in actu, habere aliquam virtutem, per quam faciat immaterialia in actu, abstrahendo a conditionibus individualis materiae (quae quidem virtut dicitur intellectus agens), et aliam virtutem receptivam huiusmodi specierum quae dicitur intellectus possibilis, in quantum est in potentia ad huiusmodi species” (Sum. Theol., 1ª, q. 79, a. 4, ad 4). The collaboration between the agent intellect and the phantasm takes place in a twofold order of causality: first, insofar as the phantasm presents the “matter” of knowing, the object in its concreteness, which must pass into universality through the efficacy of the agent intellect’s illumination; and then insofar as the phantasms, thus illuminated, become the “instrumental cause” by means of which the agent intellect impresses the species of the intelligible, or impressed species, upon the possible intellect (Quodlib., VIII, 3; Sum. Theol., 1ª, q. 85, a. 1, ad 4). This collaboration is at once the reflection and the sign of the substantial union of soul and body, and for s. Tommaso expresses the indispensable condition of all our knowing; at its first emergence no less than in the use of knowledge already acquired, the intellect needs to refer itself to the phantasms (“conversio ad phantasmata”); it does not “think intelligible essences except in the phantasms” (De Anima, III, 7, 431 b; Sum. Theol., q. 84, a. 6–7). The manner, however, of this reference or conversion to the phantasms, although uniform in the initial knowledge of simple apprehension, differs in the final knowledge of the different orders of constituted sciences, which involve affirmations and negations and therefore explicit attributions concerning the mode of being of things in themselves.
3. Insofar as it includes pronouncing upon being through affirmations and negations, a. belongs to judgment and is subject to truth or falsity according as its attributions conform or fail to conform to reality. The a. of simple apprehension, however, is not subject to this, since it abstracts from every attribution and is limited to presenting a content; for it the Aristotelian axiom applies: “Abstrahentium non est mendacium” (Phys., II, 2, 193 b, 35).
There are two principal forms of abstraction: one occurs when the whole is abstracted from the parts and a universal from the particular, as animal from man; the other when form is abstracted from matter (Sum. Theol., 1ª, q. 40, a. 3). The first includes, in different respects, the initial confused cognitions and the notions of logical abstraction; the second, on the other hand, comprises the fields of the sciences (il Gaetano coined the terms “total” abstraction and “formal” abstraction). For s. Tommaso, not every abstraction can be called a praecisio, or separation from the og-
object of departure: it is the abstraction of the whole from the parts and of the singular from the universal, but not that of form from matter, unlike those Scholastics who more or less identify them (nominalism, Suárez). The divergence arose from the fact that, for these Scholastics, as for the Augustinians, the first object of the intellect is the singular substance and not the universal nature—or rather, the most indeterminate notion of being, as the Angelic Doctor holds. The reason for the divergence is to be found in the different metaphysical conception concerning act and potency, matter and form: the anti-Thomists, since they attribute a certain act to matter and potency, both formal and entitative, make the singular individual the object—indeed, the first object—of direct intellection; consequently, they conceive abstraction as a separation or «praecisio» that the intellect subsequently performs within that global content.
Abstraction is opposed to «intuition» (v.). In man, it is the (external) senses that possess intuitive knowledge, insofar as sensible qualities are made present in them in the concreteness and singularity that they have in things. For this reason s. Tommaso rejected the «agent sense», advanced by certain Averroists, and was thus able to secure the direct contact of human knowing with external reality (Sum. Theol., 1ª, q. 79, a. 3, ad 1). In a less rigorous sense, the immediate apprehension of the first notions and first principles may be called «intuition»; in this sense some modern Thomists speak of an «abstractive intuition», even though the term seems almost contradictory. The abstraction that leads to the first notions and first judgments, since it cannot presuppose any other knowledge in the soul, takes place in the form of an «induction» (v.) which is not, however, scientific induction, but a process «sui generis» (Post. Anal., II, 19, 99 b, 23 sgg.; Metaph., I, 1, 980 b, 28 sgg.).
In the moral and mystical sense, abstraction signifies liberation from the conditions and inclinations of sensibility and may assume various forms, from those acquired through the exercise of temperance and ascetic detachment to those caused by a higher being, which are called «alienations» and «raptures» and may proceed either from divine virtue or from diabolical virtue, and sometimes also from particular bodily dispositions of the subject (Sum. Theol., 2ª-2ª, q. 15, a. 3; q. 175, a. 1). Abstraction caused by God constitutes the state of «ecstasy» (v.).