"There are two distinct ways of investigating the phenomena of mind," says Professor Sully. "In the first place, I may reflect on my own mental processes at the time of their occurrence or immediately after their occurrence. In this way, for example, I can note a succession of thoughts, or a colouring or biassing of the thoughts by a feeling of anger. This way of approaching mental processes is known as the direct or internal mode of observation, or as introspection (from intro, inwards, and spicere or specere, to look). In the second place, I may study a mental process in another mind so far as this clearly betrays itself in outward manifestation. Thus in listening to a person's talk I can note the connections which his mind forms between certain ideas, in watching his actions I am able to study the play of his motives. This is called the indirect or external way of investigating mind, because we are here getting at mental facts indirectly through the medium of certain external manifestations perceived by the senses, as the audible word or cry, the visible movement or change of colour" (" The Teacher's Handbook of Psychology," p. 17). § 4. The study of Psychology is older than its name, which is used for the first time towards the end of the sixteenth century. But we have mentioned the Socratic maxim (possibly due to Thales) of yvôi σeavтóv-know thyself. Aristotle wrote a work entitled περὶ ψυχῆς, Οι 66 On the Soul," where he discusses the faculties of the mental part of man, which for him are identical with soul and life. 66 The French philosopher René Descartes (1596-1650) gave to Psychology a new direction. In reply to the question, How do I know that I exist? Descartes replied in his famous utterance, "Cogito, ergo sum: know that I think and that I am conscious of thinking, therefore I know that I exist." The sources from which the mind derives its knowledge are, as it has already been pointed out, twofold-intuition and experience. John Locke (1632-1704), the English philosopher, in his "Essay concerning Human Understanding" (1690), treated the question of innate ideas 1 In three books. (of inner and outer perception). According to him the human mind is a sheet of white paper upon which experiences, entering through the gates of the senses, leave their impressions. In this way we gather our knowledge by sensation and reflection. In the last century, under the influence of the positive doctrines, a new tendency arose to separate Psychology from Philosophy, and establish it as a pure science on the same lines as Physiology, since it has nothing whatever to do with metaphysical problems. [Psychology, treating of the operations of the mind, will, therefore, after its general investigations, endeavour to discover and establish the laws and rules which guide thought. It will treat of the methods how to think, and how to arrive at a true conclusion by means of thought. It thus gives rise to a separate branch of Philosophy which we call Logic.] CHAPTER V LOGIC § 1. IN one of Molière's plays, Le Bourgeois Gentilhomme, Monsieur Jourdain, the rich shopkeeper who wishes to play the gentleman and to improve his neglected education, is surprised when the professor of languages whom he has engaged informs him that language is either prose or poetry, and that everything that is not poetry is necessarily prose. "And what am I speaking?" asks the astonished bourgeois. "You are speaking prose," replies the professor. "So I have been speaking prose all my life," says M. Jourdain, "without my knowing it," and in his delight he hastens to inform his wife and household of the new discovery. Many a man, frightened at the mere mention of Logic or at the suggestion of studying a book on the subject, would be as surprised as M. Jourdain, were he informed that he had been and still is applying Logic in his daily conversation, in his arguments with his household and his friends, in the exposition of his political and religious opinions and convictions. When a theory is enunciated, a statement made, an opinion expressed, we listen to and understand them, but they do not impress themselves on our mind until proved. We analyse and test the statements made, the theories enunciated, the opinions expressed, and if they are correct, we arrive at such judgments that necessarily impress themselves upon our minds and upon those of others. We arrive at conclusions that strike us to be nothing but true. If we act in this way we are said to think logically 20 or correctly. Logic, therefore, is the science of correct thinking. Its objects are the laws, the necessary and sufficient conditions by which we arrive at a correct judgment, a judgment that must be generally accepted by every normal thinking man. Under what conditions is a judgment correct? How are we to test its validity and correctness, and make sure that it is not a fallacy? Such are the questions with which Logic concerns itself. It not only teaches us how we think and must think, but also how we ought to think. It analyses correct reasoning and the process by which we arrive at a valid conclusion, and it shows the invalidity and fallacy of thought that does not conform to the rules. Many a man therefore who will readily indulge in the Mephistophelian sneer when referring to Logic— For this I counsel my young friend A course of Logic to attend ; Thus will your mind, well trained and high, is nevertheless a logician to some extent, and performs the logical operation of the mind without reflecting upon the theory of the process. He observes the laws of correct thinking without knowing them, nay, without even being aware of their very existence. § 2. If we now examine the nature of thought, we find that its process consists of three operations of the mind. First, we become aware of a sensation, receive an impression, form a concept or name of a thing or of an idea. This is the simple act of apprehension. We then begin to bring two notions or ideas together; we combine or separate them, add or subtract, and thus form a judgment or an assertion. Some such judgments appear to us correct, others invalid; and as we are always striving to arrive at judgments acceptable not only to ourselves but also to others, we endeavour to find reasons, and to prove why a judgment is true or false. For this purpose we compare one assertion with another, we consider the relation of one judgment to another, we argue from the first statements, which are called " premises," and arrive at a new statement, "the proof," which is termed con clusion." 66 Now, there is no need to enter upon the important and much-discussed question whether concepts can exist without words, and in how far is it possible to think without words. It has been and is still a matter of dispute amongst psychologists and logicians, who maintain either that it is possible to think without the aid of language or that thought without language is a mere phantom. Max Müller repeatedly stated and abundantly proved that thought and language are identical. 66 "What we have been in the habit of calling thought," says he, "is but the reverse of a coin, of which the obverse is articulate sound, whilst the current coin is one and indivisible, neither thought, nor sound, but words." Though his theories are disputed, it is, however, practically admitted that when we reason or infer we perform this operation by means of words, and it is of course generally agreed that we communicate our thoughts by outward sounds or words. We give a name to a thing we have in our mind and express it by a certain word, which is then called a "term." By joining two or more terms" with a verb, we express an idea or a judgment, which is called a "proposition," or an assertion expressed in words. Proceeding then to justify our assertion, to prove its veracity, or to give reasons for our acceptance or rejection of some one else's statements, we argue, make another statement, infer and draw conclusions. The arguments made up from propositions are called syllogisms. Logic, therefore, as the science of correct thought or reasoning, has to deal with terms, propositions, and syllogisms. The importance of a correct employment of terms is very obvious. How often does it happen that we differ in opinion from each other, that we discuss a matter and apparently dissent, although in reality we agree, and often find it out in the end? The misunderstanding is due to nothing but to a wrong employment, to an ambiguity, to a confused or vague definition of terms. "Define your terms," Voltaire therefore always urged before starting a discussion. A correct knowledge of terms is indispensable |