III. for drinking, for cooking, for brewing, for washing, LECT. for irrigation, for navigation, etc. In like manner, Logic in itself is one :-as a science or an art, it is single; but, in its applications, it is of various and multiform use in the various branches of knowledge, conversant be it with necessary, or be it with contingent matter. Or further, to take the example of a cognate science, if any one were to lay down different grammars of a tongue, as that may be applied to the different purposes of life, he would be justly derided by all grammarians, indeed by all men; for who is there so ignorant as not to know that there is but one grammar of the same language in all its various applications?" Thus, likewise, there is only one General method of reasoning, which all the sciences indiffer- alone one; ently employ; and although men are severally oc- Logic is cupied in different pursuits, and although one therefore, entitled a Theologian, another a Jurist, third a Physician, and so on, each employs the same processes, and is governed by the same laws, of thought. Logic itself is, therefore, widely different from the use, the application of Logic. For Logic is astricted to no determinate matter, but is extended to all that is the object of reason and intelligence. The use of Logic on the contrary, although potentially applicable to every matter, is always actually manifested by special reference to some one. In point of fact, Logic, in its particular applications, no longer a See Rami Sch., p. 350, [P. Rami Schola in Liberales Artes, Basilea, 1578: "Unus est Lutetiæ Sequana, ad multos tamen usus et varios accommodatus, lavandum, aquandum, vehendum, irrigandum, coquendum: sic una est Logica, varii et multiplicis usus, in propositione necessaria, pro is, a babili, captiosa; ars tamen una. Si Logic is Special manifold, and part of the science in which it is applied. III. LECT. remains logic, but becomes part and parcel of the art or science in which it is applied. Thus Logic, applied to the objects of geometry, is nothing else than Geometry, Logic, applied to the objects of physics, nothing else than Natural Philosophy. We have, indeed, certain treatises of Logic in reference to different sciences, which may be viewed as something more than these sciences themselves. For example, we have treatises on Legal Logic, etc. But such treatises are only introductions,-only methodologies of the art or science to which they relate. For such special logics only exhibit the mode in which a determinate matter or object of science, the knowledge of which is presupposed, must be treated, the conditions which regulate the certainty of inferences in that matter, and the methods by which our knowledge of it may be constructed into a scientific whole. Special Logic is thus not a single discipline, not the science of the universal laws of thought, but a congeries of disciplines, as numerous as there are special sciences in which it may be applied. Abstract or General Logic, on the contrary, in virtue of its universal character, can only and alone be one; and can exclusively pretend to the dignity of an independent science. This, therefore, likewise exclusively con cerns us. LECTURE IV. INTRODUCTION. LOGIC-III. ITS DIVISIONS-PURE AND MODIFIED. IV. Recapitula In my last Lecture, after terminating the considera- LECT. tion of the second introductory question, touching the Utilities of Logic, I proceeded to the third introduc- tion. tory question,-What are the Divisions of Logic? and stated to you the two most general classifications of this science. Of these, the first is the division of Logic into Objective and Subjective, or Systematic and Habitual; the second is its division into General and Special, or Abstract and Concrete. To speak only of the latter:-Abstract or General Logic is logic viewed as treating of the formal laws of thought, without respect to any particular matter. Concrete or Special Logic is logic viewed as treating of these laws in relation to a certain matter, and in subordination to the end of some determinate science. The former of these is one, and belongs alone to philosophy, that is, to the science of the universal principles of knowledge; the latter is as manifold as the sciences to which it is subservient, and of which it, in fact, constitutes a part,-viz. their Methodology. This division of logic is given, but in different terms, by the Greek Aristotelians and by the Latin schoolmen. The Greek division does not remount to Aristotle, but it is found in his earliest expositor, Alexander IV. LECT. of Aphrodisias, and he was probably not the first by whom it was enounced. It is into διαλεκτικὴ χωρὶς πрayμáτшv, Logica rebus avulsa, that is, Logic merely formal, Logic apart from things, in other words, abstract from all particular matter; and dialektikỳ Ẻv χρήσει καὶ γυμνασίᾳ πραγμάτων, Logica rebus appli cata, that is, Logic as used and exercised upon things, in other words, as applied to certain special objects. The division of Logica Logica utens, mis taken by some modern authors. This distinction of Logic by the Greek Aristotelians seems altogether unknown to modern logicians. The division of Logic by the scholastic Aristotelians is the same with the preceding, but the terms in which it is expressed are less precise and unambiguous. This division is into the Logica docens and Logica utens. The Logica docens is explained as logic considered as an abstract theory, as a preceptive system of rules, quæ tradit præcepta;" the Logica utens, as logic considered as a concrete practice, as an application of these rules to use,-"quæ utitur præceptis."" This scholastic division of Logic into docens and docens, and utens has, I see, been noticed by some of the more modern authors, but it has been altogether mistaken, which it would not have been had these authors been aware of the meaning in which the terms were employed, and had they not been ignorant of the more explicit expression of it by the Greeks. Thus the terms docens and utens are employed by Wolf to mark a distinction not the same as that which they designate in the scholastic logic; and as the Wolfian distinction will not stand the test of criticism, the terms themselves have been repudiated by those who were not aware, that there was an older and a more a Smiglecii Logica, Disp. ii. q. vi. For scholastic authorities, see Aqui nas, In IV. Metaph., lect. iv.; Scotus, Super Univ. Porphyrii, q. i.—Ed. a IV. valid division which they alone properly expressed. LECT. Wolf makes the Logica docens, the mere knowledge of the rules: the Logica utens, the habit or dexterity of applying them. This distinction of General and Special logic, Wolf and the Wolfian logicians, likewise, denote by that of Theoretical and Practical Logic. These terms are in themselves by no means a bad expression of the distinction, but those by whom they were employed unfortunately did not limit their Practical Logic to what I have defined as Special, for under Practical they included not only Special, but likewise Modified Logic, of which we are now to speak. Having explained, then, this primary division of Logic into General and Special, and stated that General Logic, as alone a branch of philosophy, is alone the object of our consideration; I proceed to give the division of General Logic into two great species or rather parts,—viz. into Pure or Abstract, and Modified or Concrete. General vided into Pure and Modified. ¶ VIII. In the third place, considered by refer- Par. VIII. ence to the circumstances under which it can Logic, dicome into exercise by us, Logic,-Logic General or Abstract, is divided into Pure and Modified ;a division, however, which is perhaps rather the distribution of a science into its parts than of a genus into its species. Pure Logic considers the laws of thought proper, as contained a priori in the nature of pure intelligence itself. Modified a [As Krug.] [See his Logik, § 11, p. 30. Compare Kant, Logik, Einleitung, ii.-ED.] B Wolf, Philosophia Rationalis, § 8, 9, 10, 12.-ED. [Cf. Stattler, Sauter, and Mako.] [Stattler, Logica, § 18, p. 12; Sauter, Positiones Logi- |