Rationale

RATIONALE. - That which belongs to reason
(v.) or is in conformity with it. In this sense, demonstration (v.), deduction (v.) are called r., as is the very activity of reason consisting in combining concepts and propositions.

Also a r. act is "judging well" (Descartes, Disc. de la mét., I, 1), that is, the act that knows how to distinguish the true from the false, good from evil, etc. Likewise, natural truth is called r., to distinguish it from superrational revealed truth (v. RAZIONALISMO); and r. is also the system of a priori principles, logically formulated, whose origin and value are independent of sensory experience. Hegel (v.), who makes the concept (v.) the essence of things, identifies the real and the r.: "everything that is r. is real; and everything that is real is r." (Filos. del diritto, preface). Other particular meanings are not lacking: for example, in the sense of "good method" (a "r. education," a "r. distribution" of the parts of a subject, etc.). Mathematicians speak of a "r. number," that is, one that can be put in the form of a ratio between two whole numbers; and physicists of "r. mechanics," that is, mechanics constructed by a purely deductive method starting from the notions of mass, force and inertia.

Cournot opposes "logical" order and "r." order; the former, according to him, is linear and discursive, the latter synthetic and intuitive; logical order determines assent (v.) without showing the true reasons of things; r. order, on the other hand, joins truths to their natural principle and enlightens the mind. As is well known, modern rationalism and Kant oppose r. to empirical.

Although the two terms are often used indifferently, it is more exact to distinguish r. from "reasonable," which indicates reason that shuns extremes and, in general, whatever is sound and normal. From the moral point of view, reasonable is one who knows how to restrain his own passions or his own instincts, desires, etc., that is, one who knows how to make good use of reason. "Due measure" too is rationality, and whoever conforms to it is reasonable and also r., insofar as there is no reasonableness without norms and principles. But the word r., in this sense, also has its negative sides: a r. spirit can indicate a cold or indifferent man, self-interested and calculating, that is, poor in feelings (or a despiser of them) and of scant intuition (v.). There is also a pejorative sense referring to reason itself: when reason claims to rationalize everything - in the specific sense of reason as the principle of logical-conceptual determinations and relations - and denies what is not rationalizable, it is r. but not reasonable. Reasonableness is rationality made penetrating by intelligence and vivified by feeling. "It is necessary to have enough reasonableness not to be purely r. or passionate, enough warmth of feeling to make reason human and enough strength of reason to purify and enlighten feeling" (M. F. Sciacca, Filosofia e metaf., Brescia 1950, p. 233).

Michele Federico Sciacca