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CHAPTER IV.

TRUTH, AND THE RELATIONS THERETO OF LOGIC-DEFINITION OF LOGIC.

§ 43. While Truth in general may be regarded as a harmony or conformity between thought and reality, or more precisely, between thought as representative and fact as given in intuition or presented, it is to be observed that the consciousness of truth as a mental act implies a synthesis, or composition of notions or terms as one, or better as in one.1

So long as notions or terms are in the mind apart from this synthesis, we have not properly either truth or error. And this applies equally to nouns and verbs,-for the verb, apart from its relation to time or assertion, is essentially an attribute or noun. Notions out of combination, and combination as one, are merely representations devoid of truth or error. The notion, for example, of goat-stag (TpayAapos) may be in the mind, but it is neither true nor the reverse, until it is added that it is, or is not, either absolutely or in some determinate time.2

A sentence even may be significant without being properly either true or false, as in the case of the expression of a prayer or wish. The sentence which admits of truth or error must be enunciative (årоpaνтiкós),-represent two notions or terms as in or not in one and the same subject, -in other words, affirm or deny." There is the assertion of a relation of identity or congruity, or the denial of this, between the notion or term spoken of, and that which is 1 Σύνθεσίς τις ήδη νοήματων ὥσπερ ἐν ὄντων. 2 Cf. Aristotle, De Int., c. i.

3 De Int., c. iv.

spoken of it. This synthesis of thought is expressed in that form of words into which the verb enters, as Water cleanses— man is organised.

§ 44. It may be a question as to whether, and in what sense, concepts by themselves are true or erroneous. If concepts be regarded as representative of reality or things,and such is their essential character,-then they may be correct or incorrect representations. Man, animal, organised, are concepts; each contains a series of attributes, and they have a relation to objects considered as possessing those attributes. So all scientific concepts,-chemical affinity, gravitation, &c. If they represent the attributes in the objects of the class correctly, they are true; if incorrectly or imperfectly, they are false or inadequate. This, however, may be regarded as a potential truth or error. Until the concept is declared adequate to the object of the class, or until the attributes of a concept are actually referred to the subject, they have but an ideal reality, and cannot be said to be actually true or the reverse. Synthesis, composition, the regarding as one of a plurality,the object and concept, the subject and attribute, is essential to truth,-in other words, there is need of actual predication. The point to be kept in view regarding the concept is, that it is not a mere work of framing or fiction at the arbitrary pleasure of the mind, but determined and constituted by and in accordance with the nature of things. As Aristotle well puts it, referring, however, actually to enunciation, expressions are similarly true as things—'Oμoíws oi λόγοι ἀληθεῖς ὥσπερ τὰ πράγματα. (De Int., c. ix.)

(a) The name of truth has been improperly given "to the mere reality of existence, altogether abstracted from any conception or judgment relative to it, in any intelligence human or divine. In this sense physical truth has been used to denote the actual existence of a thing. Some have given the name of metaphysical truth to the congruence of the thing with its idea in the mind of the Creator. Others again have bestowed the name of metaphysical truth on the mere logical possibility of being thought; while they have denominated by logical truth the metaphysical or physical correspondence of thought with its objects. Finally, the term moral or ethical truth has been given to veracity, or the correspondence of thought with its expression."(Hamilton, Logic, L. xxvii.)

(b) He judges truly who thinks that what is divided is divided, and what is combined is combined; but falsely who thinks contrarily

to things as they are.-(Met. ix. 10.) In other words, truth is not the mere licence of thought, but lies in the act of thought, which is conformed to the nature or reality of things. Truth in modern language is defined as the harmony of thought with the thing itself, or of the subjective with the objective. (Cf. Trendelenburg in loco.)

A true sentence is by no means the cause of a thing's existence, but in some way the thing appears the cause of the sentence being true, for in consequence of a thing existing, or not existing, is a sentence said to be true or false.-(Cat. xii.)

It is the combination of our thoughts which gives us truth or error, but the reality which serves as their basis is absolutely independent of human thought.—(De Anima, iii. 8, 432a, 11. Cf. Ibid. 6, 430b, 1.)

As Bacon puts it: "Scientia nihil aliud est quam veritatis imago; nam veritas essendi et veritas cognoscendi idem sunt, nec plus a se invicem differunt, quam radius directus et radius reflexus."(N. O., I. Aph. xiii.)

§ 45. Formal Logic, though concerned with truth, does not consider all the laws, conditions, and methods through which we are to reach the harmony of thought and reality, the principles, in particular, of observation, classification, generalisation, induction of causes. At the same time, it is not to be regarded as divorced from the conditions of our knowledge of the real. The laws with which it deals relate to the form and very possibility of our knowledge, and essentially to the connection and development of our knowledge. They are laws of the ideal possibility of an object of thought, of the consistency of our objects of thought, and of the necessary connections of the matter of our thought. Logic, as it has been defined, is "the science of the laws of thought as thought." Other equivalent expressions are "the science of the formal laws of thought," "of the laws of the form of thought," "of the necessary form of thought." 3

1

These expressions, when fully explicated, bring out the essential character of Formal or Deductive Logic. For they can be shown to contain the points (1) of the ideal possibility of any object of thought, (2) the consistency of attributes in an object, (3) the necessary implication of one judgment in another, whether as in immediate inference or as in reasoning.

(a) By some writers Logic is defined simply as the Science of Reasoning. This is inaccurate. It is the Science of Thought in its three forms of Conception, Judgment, and Reasoning. These are all equally forms of the same fundamental power,-that of Comparison. 3 Ibid., L. iii.

1 Hamilton, Logic, L. i. par. 1. 2 Ibid., L. i.

They are essentially related; no adequate theory of reasoning can be given without a previous consideration of conception and judgment. Farther, the laws which regulate reasoning are already exemplified in conception and judgment. This mistake of limiting Logic to the theory of Reasoning was long ago corrected by intelligent logicians, as Smiglecius, who maintains that neither Argumentation, as held by Albertus, nor Syllogism, as by Sextus, nor Demonstration, as by the Greeks, is the adequate object of Logic, but that this is found in the three operations of the mind in as far as they are dirigible—qua dirigibiles, or capable of direction to an end. Dirigibility belongs to the operation as such; and through this quality only, through the abstract laws and forms of the operations, can Logic be said to embrace all things. (Smiglecius, Logica Disp., ii. 9. 1.)

(b) This definition of Hamilton is related to the view of Kant as to the sphere of Logic: Kant's view of General Formal Logic is that it is the rational science of the necessary laws of thought, as these refer to all objects generally, or all objects whatever. It is the science of the pure form of thought. This science is divided into Pure and Applied. Pure considers the Understanding in itself; Applied deals with the Understanding in its conjunction with the other faculties. Pure General Logic is divided into the Doctrine of Elements and the Doctrine of Method. Special Logic treats of the special methods of the particular sciences.—(Cf. Logik, and Ueberweg, § 28.)

Kant's full conception of Logic is as follows:

"Logic is a rational science, not only in respect of mere form, but also of matter; a science a priori of the necessary laws of thought, not by relation to particular objects, but by relation to all objects in general: it is, consequently, the science of the legitimate use of the Understanding and the Reason in general; science not subjective, that is to say, executed not according to empirical principles (psychological), but science objective, that is to say, made after principles a priori determining the manner in which the understanding ought to think.

"If we make abstraction of all knowledge which we can acquire only on occasion of objects, and reflect only on the use of the understanding in general, then we shall discover those rules which are absolutely necessary under all relations, and without any regard to the particular objects of thought, because that without them there would be no thought. These rules may thus be considered a priori, that is, independently of all experience, because they contain simply, without distinction of objects, the conditions of the exercise of the understanding in general, whether it be pure or experimental. Whence it follows at the same time that the general and necessary rules of thought can concern only the form, and not the matter. The science of these necessary and universal rules is therefore simply the science of the form of our intellectual knowledge or thought. We can thus frame the idea of the possibility of such a science, in the same way as we form the idea of a General Grammar. This contains but the simple form of language in general, and not the words which constitute the matter of languages.

"This science of the necessary laws of the Understanding and of Reason in general, or which is the same thing, of the simple form of thought in general, is that which we call Logic."—(Logik, Introd., § 1.)

§ 46. Esser's argument, adopted by Hamilton, for the formal character of Logic is in substance that, if the science were to take account of the matter or objects regarded as realities, it must either consider all cogitable objects, or some only. If the former, it would be the one universal science, an impossible science. If the latter-if it were to take cognisance of certain objects only on their real side,-it would do so arbitrarily, or without ground of selection. This would not be a scientific procedure. Logic has thus no immediate concern with that which is thought about. It is thus a science of the form of thought.1

(a) No one has put this more clearly than Occam. Logic, he says, is a rational science, dealing with those objects which cannot be without reason,—not real, which refers to things existing apart from the mind. Whether man be species, rational difference, white an accident, cannot be determined by logic, because these points cannot be known apart from a perfect knowledge of the nature of the thing signified by the subject. There would thus be no perfect science of logic, unless the logician knew the nature of all things-nay, unless he knew all the conclusions and all the principles of all the sciences. Such propositions are only pertinent to logic as a science, in the way of examples.-(Expos. sur Procm. and Summa totius Logicæ, iii. 2, 22, f. 53. Prantl., Ges. d. Logik, iii. 744.) He also tells us that Logic is practical, inasmuch as it directs the intentions of the mind, which are our own acts, such as judging and reasoning, and not external things, unless in a secondary way, which are beyond our power.-(Expos. sur Proœm. Prantl., iii. 742.) The part of logic which deals with the categories is speculative, inasmuch as their objects are not our operations.-(Præd. Proœm. Prantl., iii. 743.)

Whether terms, propositions, syllogisms, which we make, exist only subjectively in the mind, or in some other manner, belongs not to logic to consider, but to metaphysics. (Occam, Expos. Am. Procem. Prantl., iii. 756.)

Again: It is incorrect to allege that some definition of man is logical, some natural, some metaphysical, because the logician, since he does not treat of things which are not signs, does not treat of man nor has to define man, but has to teach in what mode other sciences treating of man have to define him. The logician, therefore, ought to assign no definition of man, except by way of example.-(Log., i. 26.)

(b) It was a question with the earlier schoolmen whether logic was of things, or concepts, or words (de rebus aut de conceptibus aut de 1 Logic, L. i.

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