Rationalism

RATIONALISM. - A philosophical term, relatively recent (it entered usage with English Deism [v.] in the 17th century) and rich in meanings. Three fundamental ones can be distinguished: 1) metaphysical sense; 2) epistemological sense; 3) religious sense.

1. Metaphysical sense

Everything has a reason for being, and there is nothing, at least in principle, that is not rational. Reason (v.) is, in short, the first principle of universal intelligibility, and everything that exists, in itself even if not for us, is reducible to the essential laws of rational thought, understood as the principle of reason of things, even if the inadequacy of our cognitive means cannot grasp entirely this profound rationality of the universe in its unity and totality. In this sense r. can be pantheist, theist and, if the term is permitted, semi-pantheist: pantheist if it identifies the rationality immanent in the world with God himself (Stoicism, Plotinus, Spinoza, Hegel, etc.), theist if it derives it from the creative act of God, who is transcendent with respect to the world (Plato, St. Augustine, St. Thomas, Vico, etc.); semi-pantheist if it does not identify God with the principle of reason immanent in the world, but makes of the world itself, in its universal "harmony," the "best of all possible worlds," which God could not fail to create by moral necessity (Leibniz). In all these cases, however, it is admitted that: a) the world has an order and an end, and nothing in it is left to chance; b) if it seems otherwise to us, this is due to the imperfection of our knowledge and to our limits as finite and contingent beings, who cannot discern the great "economy" of the universe, owed either to the immanent Reason that governs it (pantheist thesis) or to Providence that realizes a mysterious divine plan (theist thesis).

2. Epistemological sense

The only source of knowledge of truth is reason, an essential and exclusive faculty for this purpose. In this sense, r. is opposed to all forms of sensualism (v.) and empiricism (v.), which assume as sources of truth (and of every truth) the associations, classifications, schematizations that the intellect makes of sense data. From this point of view, one can speak of a r. of Socrates (v.) and Plato (v.) that is opposed to the sensualism of the Sophists (v.); of Descartes and Leibniz (v.) that is opposed to the empiricism of Locke (v.), etc. Naturally, not all forms of epistemological r. display equal rigidity and exclusiveness. In antiquity this character belongs to the r. of the Eleatic school and above all of Parmenides, who considers all sense experience illusory and deceptive: Justice, who "holds the keys that open and close" (that is, reason), welcoming the philosopher, declares two things to him: that there is the domain of science, which is "well-rounded truth," and the domain of opinions, which do not deserve belief, that is, there is being, which is intelligible and of which there is truth, and there is not becoming (the sensible), which is appearance and of which there is only opinion (Sextus Emp., Adv. math., VII, 111 ff.). One must judge not with "the eye that does not see" and with "the ear that resounds with illusory sounds," but with "reason" (ibid., VII, 114), the only thing that affirms the unity of being. Socrates and Plato attenuate the intransigence (and abstractness) of Eleatic r., and neither the one nor the other denies the importance of sense nor excludes sensation from the cognitive process. With Plato, however, r. takes on the essential character of "innatism" (v.) which, with various nuances or deepenings, will be preserved by the entire Platonic current: there exist in the human soul knowledge-principles or rational forms, etc., prior to every external experience and which reflection (v.) discovers. Sensation is nothing but "the occasion" for awakening in the soul the innate forgotten knowledge (see especially the Meno). This allows Plato not to exclude and devalue the intermediate degrees of knowledge (see especially the Theaetetus), but does not allow him to grasp the true value of the sensible and of sensing. For him true knowledge is that which is intellectual (νόησις) and discursive (διάνοια), which is directed toward the Ideas, the beings that always remain identical to themselves and that can be apprehended only by thought (Phaed., 79 a), the only thing that makes us acquire truth and wisdom (ibid., 66 a; Resp., 508 d). Aristotle (v.) eliminated Platonic innatism and vindicated the value of sense knowledge as the origin of all our knowledge, always leaving the primacy to rational truth. "Of all things we have certainty either by syllogism or by induction. We learn either by induction or by demonstration. Demonstration proceeds from universals, induction from particulars" (Analyt. pr., II, 23, 68 b 13). These two classical forms of r. are found again in Christian Platonism (St. Augustine, St. Bonaventure) and in Christian Aristotelianism (St. Thomas), deepened, the first in the sense of the "interiority" of truth (different from innatism) and the other, which contains strong Platonic-Augustinian elements, in the sense that, besides ratio, it admits (as indeed Augustine does) intellectus, a higher and intuitive faculty of knowing, although the one and the other are not two different powers: "Etsi intellectus et ratio non sint diversae potentiae, tamen denominantur ex diversis actibus. Intellectus enim nomen sumitur ab intima penetratione veritatis, nomen autem rationis ab inquisitione et discursu" (Sum. Theol., 2ᵃ-2ᵃᶜ, q. 49, a. 5 ad 3).

But the term r. acquired a precise philosophical meaning, which is the one now in use, only with so-called modern r. from Descartes (v.) to Wolff (v.): there exist in us a priori principles (innate, albeit in a "virtual" state) evident in themselves, of which every true cognition is a necessary consequence, to which the senses add nothing. It should be borne in mind that modern r. develops simultaneously with the formation of modern science: r. and scientism are inseparable. Hence the demand for a purely rational truth, capable of dominating and ordering the confused material of sense experience. But both r. and empiricism (v.), which opposes it, do not yet have a critical concept of experience itself and confuse it with the "empirical datum": therefore r. loses itself in an apriorism of forms without content and empiricism in the mass of sense data without a rational form valid for the purposes of the discovery and conquest of truth. R. also means rational dominion over reality and the autonomy of reason itself from every other authority: if reason is innate to man and in it are innate the principles of every truth, it is independent of tradition, it is founded upon itself, it rejects everything that is not reducible to it, it "criticizes" every other authority, it constructs for itself its "natural" law, its "natural" morality (no longer of divine origin, the one and the other), its "natural" religion (without dogmas and without Revelation). For r. it is enough that reason be free to realize itself fully for total truth to be actualized and for a wholly rational knowledge, entirely complete and absolutely perfect. Thus r. presents itself as the revolt against tradition (including religious tradition) and history, beginning with its founder R. Descartes, whose Discourse on Method is its manifesto (see especially part 2). From the gnoseological point of view the position of r. seems well defined by Leibniz: "The knowledge of necessary and eternal truths is what distinguishes us from mere animals and makes us have reason and the sciences, raising us to the knowledge of ourselves and of God" (Monadology, no. 29), without sense experience having anything to do with it: "Pure and naked reason, distinct from experience, has to do only with truths independent of the senses" (Theodicy, Disc. on Conformity, 1). Thus r., linked to science (v.) and to its development, dogmatically assumes as the typical truth of knowing that physico-mathematical truth: rational construction of the world, deduced a priori by analysis and culminating in a Cause or in a Law, identified with God, which guarantees the perfect functioning of that "machine" which is the cosmos. Therefore "the critical position of r. is not a critique of reason, but of what is not reducible to rational knowing: the absoluteness of reason, dogmatically assumed, is critically employed as the measure by which everything must be measured... Everything for r. is rationally clear and what is obscure is a lower degree of knowledge; all problems are well defined and solved: reason matches the natural order and the natural order satisfies the demand of reason. In a world without philosophical enigmas, religious mysteries, the fruit of fanaticism and superstition, are no longer needed, as the barbaric scientism and the superficial philosophism of the Enlightenment [v.] conclude" (M. F. Sciacca, L'interiorità oggettiva, Milan 1952, pp. 53-54).

It is precisely this "reason" of r. that criticizes empiricism to the core, objecting that every human cognition derives from sense experience, which is the insurmountable limit of reason. Into this duel there enters the criticism of Kant (v.), in which r. acquires a new meaning in relation to the new meaning that Kant gives to the term "experience" (v.). Experience is not the empirical datum: this is only the content of experience, which is possible because the spirit possesses reason, that is, a system of a priori forms that organize and systematize the empirical data. Therefore experience is a synthesis of the a priori form and the a posteriori empirical datum, which in the form finds its order and to the form gives its content. Consequently: a) the a priori principles of r. from Descartes to Wolff cease to be innate truths and become with Kant a priori "conditions" that the intellect applies to empirical or sensible data so as to raise sensory knowledge to the level of rational knowledge and to construct that synthesis which is experience; b) "knowledge through reason" (Vernunfterkenntnis) and a priori knowledge are "one and the same thing" (einerlei), insofar as it is reason that contains the principles that give a priori knowledge (Critique of Pure Reason, introd., § 7); c) but since the principles are transcendental a priori conditions and forms, their validity remains limited to empirical experience or to the phenomenon; d) and therefore Kant assumes, like empiricism, the sensible as the limit of reason and can no longer avoid metaphysical agnosticism. R. in this way, with Kantian criticism, comes to identify itself with the possibility of physics and mathematics as sciences, without, on the other hand, succeeding in avoiding the subjectivity of knowing, given that the a priori is not a truth, but only a condition (transcendental activity of the subject) of experience.

After Kant, but through the development of Kant, Hegel (v.) makes Reason the metaphysical principle, identifying "real" and "rational." For Hegel too the idea is transcendental, but no longer a function and condition of experience, but rather a metaphysical entity that, through the law of dialecticism, actualizes itself and resolves in itself all of the real, not merely the phenomenal, without the residue of the thing in itself. Thus Kantian metaphysical agnosticism (v.) is eliminated, not because Hegel (and all transcendental idealism) grounds and resolves the problems of metaphysics, but because they dissolve metaphysics into logic, that is, being into thought. Therefore, in Hegel, metaphysical and gnoseological r. are identified and dialecticism (passage from one term of the contradiction to the other and unity of the contradictories; Encyclopedia, § 81) is at once the law of thought and of the real. Thus reason once again dogmatizes itself and, in positing itself as total truth, denies its own truth and every truth in the "irrationality" of its absoluteness and in the abstractness of panlogism.

3. Religious sense

It should rather be called "irreligious," given that the so-called "natural" or "rational" religion resolves itself into the negation of religion, inasmuch as it reduces all its content of truth "within the limits of reason." Accordingly, religious r. is that doctrine or doctrinal attitude which admits of religion only those truths that can be rationally known. Strictly speaking, one cannot speak of a religious r. before Christianity, inasmuch as there was no revealed truth and hence no suprarational and dogmatic truth. Religious r. begins with English deism, according to which religious truths are accepted not because they are revealed, but insofar as they are comprehended and justified by reason. Thus the truths of faith are denied, and religion is made a grade of reason itself, or is resolved dialectically into philosophy (Hegel, Gentile), of which it is a lower grade. A doctrine in every respect heterodox (naturally condemned), inasmuch as it denies Revelation and subordinates religion to reason; in fact and by right it denies it, inasmuch as it denies dogma and the supernatural. In order to combat religious r., one must not fall into the opposite excess (itself heterodox) of the "irrationality" of revealed truth (as if it were "absurd" to reason: Kierkegaard, Barth, etc.) or into fideism (v.), which, by denying reason, loses faith itself. To religious r. one must not oppose religious "irrationalism," inasmuch as revealed truth is not against reason, but is above it without contradicting or opposing reason. Indeed, it can be defended negatively by reason (by demonstrating the contrary affirmation to be false), while remaining a suprarational and dogmatic truth. See also, for the theological aspects of r., GRACE; MYSTERY; REVELATION; SUPERNATURAL.

BIBL. on the authors cited, see the corresponding entries. On modern r. in general, bibliographical indications in Überweg, III, p. 653 ff., 683 ff. In particular: K. Fr. Stäudlin, Gesch. des Rationalismus

u. Supernaturalismus, Göttingen 1836; A. Tholuck, Gesch. d. Rational., Berlin 1865; H. Heussler, Der Rationalism. des 17. Jahrh., Breslau 1885; C. Grube, Über den Rationalism. in der neueren engl. u. franzis. Philos., (diss.), Halle 1889; W. Pasing, Spinozae Rational. (diss.), Leipzig 1893; L. Ollé-Laprun, La raison et le rational., Paris 1906; F. Enriquez, Scienza e r., Bologna 1912; M. Robertson, Rational., Edinburgh 1912; K. Girgensohn, Rationalis., Leipzig 1926; F. Enriquez-G. de Santillan, Le problème de la connaissance. Empirisme et rationalisme grecs., Paris 1938; J. Marechal, Le point de départ de la métaphysique, cahier II, 2nd ed., Brussels-Paris 1942. A broad article, particularly from the theological point of view, by C. Costantin, Rationalisme, in DThC, XIII, II, coll. 1688-1788.

Michele Federico Sciseca