Jacques Maritain Center :
Psychology / by Michael Maher, S.J.
Definition. -- Psychology (tês psuchês logos) is that branch of philosophy which studies the human mind 0r soul. By the mind or soul (psuche) is meant the thinking principle, that by which I feel, know, and will, and by which my body is animated. The terms Ego, Self, Spirit, are used as synonymous with mind and soul, and, though slight differences attach to some of them, it will be convenient for us (except where we specially call attention to divergencies of meaning) to follow common usage and employ them as practically equivalent.
Subjective and Objective. -- In modern philosophy the mind is also called the Subject, especially set in contrast with the external world, which is characterized as the Object. The adjective subjective is similarly opposed to objective, as denoting mental in opposition to extra-mental facts, what pertains to the knowing mind as contrasted with what belongs to the object known. Thus a train of thought, an emotion, and a dream are said to be subjective; whilst a horse, an election, and a war are objective realities. Such are the primary significations of these terms, but the meanings vary with different writers.{1}
An objection. -- We may here be met with the objection that we are unwarrantably postulating at the very commencement of our work the most disputed doctrine in the whole science of Psychology -- the existence of some "inscrutable entity," called the soul. To this we reply that for the present we only use the term provisionally to indicate the source or root of our conscious states. We make no assumption as regards the nature of this principle. Whether it be the brain, the nervous system, the whole organism, or a pure spirit, we do not yet attempt to decide. But we claim to be justified, in employing the familiar terms soul and mind to designate this apparent bond, by the obvious fact that our various mental states manifest themselves as bound together in a single unity.
Scope of Psychology. -- The subject-matter of our science is, then, the Soul or Mind. The psychologist investigates those phenomena which we call sensations, perceptions, thoughts, volitions, and emotions; he analyzes them, classifies them, and seeks to reduce them to the smallest number of fundamental activities. He studies the nature of their exercise and the laws which govern their operations, and he endeavours to enunciate a body of general truths which will accurately describe their chief and most characteristic features. But Psychology cannot rest here. Whether it wishes it or not, Psychology is inevitably a branch of Philosophy.{2} It cannot remain satisfied with the mere generalization of facts; it must pass on to inquire into the inner nature and constitution of the root and subject of these phenomena; it must seek to explain the effect by its cause. Consequently a work which does nothing more than describe and classify the operations of the mind, omitting all discussion regarding the mind itself, is but an abortive attempt at a science of Psychology.{3} La Psychologie sans âme, is Hamlet without the Prince of Denmark. What is the meaning and value of life? What are we? Whence come we? Whither go we? These have ever been questions of profound interest to the human race, and it is the belief that Psychology can throw some light on them which has always vested with such importance this branch of Philosophy.
Besides the fact that the chief interest for mankind in Psychology is due to the expectation that some information as regards the nature of the soul itself can be thence derived, there is another reason for the explicit treatment of these metaphysical problems here. The two sets of questions are incapable of isolation. They can never be really separated. Our final conclusions as regards many vital philosophical problems are necessarily determined by the view taken of the nature of mental activity in the empirical part of the science. The sensationalist doctrines, for instance, on perception, intellectual cognition, or volition, cannot be reconciled with the Hegelian or with the Intuitionalist conception of the mind. It is, consequently, only fair to the reader that the philosophical conclusions to which the treatment of mental phenomena presented to him logically lead, should be clearly pointed out.{4}
Empirical and Rational Psychology. -- The discussion of the former questions -- the inquiry into the character of our various mental states and operations -- is called by different writers Phenomenal, Empirical, or Experimental Psychology; whilst the investigation into the nature of the mind itself is styled Rational Psychology. Sir W. Hamilton describes this second part as Inferential Psychology, or the Ontology of the mind.{5} The term Phenomenal is applied to the first part of Psychology, because it investigates the various phenomena of the mind, the facts of consciousness. It is called Empirical or Experimental, because we have an immediate experience of these facts: we can study them by immediate observation. The second part of our subject is marked by the epithet Rational, because the truths which are there enunciated are reached, not by direct experience, but by reasoning from the conclusions established in the earlier part. In the present work we have devoted Book I. mainly to Empirical Psychology, whilst Book II. is confined to the problems of Rational Psychology. We have not, however, sought to make the division rigid: in fact, our chief contention is that a complete and accurate separation of the two branches of Psychology is impossible. Thus we have included in our First Book certain questions regarding external perception, memory, the origin of ideas, the nature of intellectual activity, and the freedom of the will which would now-a-days be usually allotted to the sphere of Rational Psychology. The two branches of the science of course employ both observation and inference; but while frequent appeal to the facts of consciousness is a prominent feature in the first stage, deductive reasoning prevails in the last. Starting from the knowledge acquired in Empirical Psychology regarding the character of the operations and activities of the mind, we draw further conclusions as to the nature and constitution of the root or subject of those activities. The knowledge of the effect leads us up to that of the cause; the mode of action indicates the nature of the agent. We may thus hope by a judiciously combined use of reasoning and observation to attain to a well grounded assurance regarding the existence of an immaterial soul, its relations with the body, its origin, and its future destiny.
Psychology and Cosmology. -- The scope of Psychology will be made still clearer by pointing out how it is connected with other kindred sciences, and how it is separated from them. In the scheme of strictly metaphysical branches of speculation it stands opposed to Cosmology, as the Philosophy of spirit to that of nature. The latter science seeks to investigate the inner constitution of matter, the nature of space and time, and the ultimate principles or laws which underlie and govern the course of the universe; while Psychology confines itself to the study of the subjective world, the mind of man.
Psychology and Logic. -- There are, however, other departments of Philosophical knowledge of a subjective character; both Logic and Ethics deal with mental activities. As regards Rational Psychology, which inquires into the nature of the mind itself, there is no difficulty in seeing how it is differentiated from these sciences, so we need only keep Empirical Psychology in view when comparing them. Both Psychology and Logic study mental states, but whereas the former embraces within its ken sensations, emotions, volitions, and all other classes of conscious acts, the latter is limited to the consideration of cognitive operations, and mainly to that of reasoning. Again, the points of view from which they approach their subject-matter is different. Psychology looks on our mental processes as natural events interesting in themselves. It seeks to describe and classify them, to explain their genesis, and to discover their laws or constant modes of action. It may, indeed, incidentally afford useful information regarding the acquisition of habits, the cultivation of the memory, and the training of other faculties; but its primary aim is speculative. Logic, on the other hand, is interested in mental operations as representative of objective fact. It is the science, not of thinking in general, but of correct thinking. It is less purely a speculative science, and in the eyes of some even its primary aim is practical. Its object is the discovery of the general canons of truth. It is, in the words of St. Thomas, "the science which teaches man how to order aright the acts of the intellect in the pursuit and attainment of truth." In a word, while Psychology studies thought merely as a subject, Logic investigates it for an object. The researches of the psychologist are directed towards the causal connections between mental states, and lead up to the apprehension of a body of natural laws -- general truths describing uniformities of succession and co-existence among such states. Those of the logician centre upon the rational correlations of intellectual acts, and result in the formulation of a code 6f normal laws -- a body of precepts -- which can be disobeyed but under the penalty of error. In addition to these points of similarity and contrast, the two sciences are related by a certain mutual interdependence. Psychology, like every other science, must conform to the rules of right reasoning; it must observe the canons of inductive and deductive inference, and it must carry out the general precepts of Logical Method. On the other hand, the validity of thought may be seriously affected by its genesis. The materials with which the logician works are products which have been analyzed by the psychologist, and, consequently, although Logic is not properly based on Psychology, a false theory of the nature of our cognitive faculties may sap the very foundations of knowledge, and lead to a disbelief in the existence of all real truth. Logic may therefore at times have to appeal to a sound system of Psychology in justification of its fundamental assumptions.
Psychology and Ethics. -- Ethics as the science of morality is easily distinguished from Psychology. It investigates the right end of human action, the nature and foundations of moral distinctions, the grounds of moral obligation, and the sanctions of morality. It classifies virtues, vices, and duties, and promulgates the rules of right conduct. Whereas Psychology considers our mental activities in their causes, Ethics studies them in their results: and while Logic seeks to harmonize cognition with the order of the physical world -- the Real; Ethics would conform volition to the order of the moral world -- the Ideal.{6} In establishing, however, the existence of moral intuitions, and in exhibiting their character, appeal must be made to the philosophy of the mind. The nature of the mental activity called conscience, the genesis of moral sentiments, the formation of moral habits, and the freedom of the will, a truth on the proof of which moral responsibility in its universally accepted sense is absolutely dependent; all these questions -- matters of the highest importance to the moral philosopher -- belong to the sphere of Psychology.
Psychology and Physiology. -- The term Biology is sometimes used in a wide sense to embrace all the branches of knowledge which treat of the phenomena of life. More, properly, it comprehends two co-ordinate physical sciences,{7} Morphology, which investiLgates the structure of living organisms, and Physiology, which investigates their functions. The latter science stands in close relations to Psychology, both Phenomenal and Rational. The physiologist studies the various operations of our vegetative life, he examines into the action of digestion, respiration, growth, nutrition, and the other vital processes which take place within us. He observes the working of our several organs, and seeks to enunciate laws that will express the general uniformities exhibited in the aggregate of operations which go to constitute our physical life. These events are perceived by the external senses, and are ultimately reducible to movements in matter.
Physiology is thus distinguished from Empirical Psychology, both by the phenomena of which it treats, and by the faculty through which these phenomena are apprehended. It is marked off on the other hand from Rational Psychology, as the positive science of the physical manifestations of life from the philosophical science which seeks to investigate into the inner nature of the subject of vital phenomena, both physical and psychical. Again, the vegetative and psychical activities proceeding from the same root reciprocally influence each other. Our sensations, intellectual operations, emotions, and volitions, are profoundly affected by the physical condition of the organism at the time, and in turn they modify the character of the functions of physical life. Consequently, as we shall see in the next chapter, Physiology forms an important supplementary source of knowledge in building up our science of Empirical Psychology.
But Rational Psychology is still more concerned with the teaching of Physiology. Its scope is to investigate the inner nature of the subject or root of both psychical and vegetative functions, and the relations subsisting between that subject and the body. It is alike interested, therefore, in the sciences of conscious and of unconscious life, and its final conclusions must alike harmonize with the established truths of Physiology and of Empirical Psychology.
Readings -- On the dignity, utility, and scope of Psychology, cf. St. Thomas, Comm. de Anima, Lib. I. ll. 1, 2 Dr. Stöckl, Lehrbuch der Philosophie, §§ 1-3; Tilmann Pesch, S.J., Institutiones Psychologicae (Friburg, 1897), §§ 19-22, 28-30.
{1} In strict language the word mind designates the animating principle as the subject of consciousness, while soul refers to it as the root of all forms of vital activity. Spirit is of still narrower extension than mind, indicating properly a being capable of the higher, rational, or intellectual order of conscious life. Ego and self strictly signify the whole person constituted of soul and body.
{2} Etymologically, Philosophy (philosophia) is equivalent to the love of wisdom, but at a very early date it had come to signify the possession of the highest knowledge or wisdom itself. Wisdom or Philosophy, thus understood, was defined as the science of things in their last causes. The term, Metaphysics, was also employed as synonymous with Philosophy to denote the science which investigates the ultimate principles of things. Metaphysics has been divided into the subdivisions: Ontology or Metaphysics proper, also called General Metaphysics, which studies the nature and attributes of Being in general, and Special Metaphysics including Cosmology, Rational Theology, and Psychology, which investigate special forms of Being. By many modern writers, the terms Philosophy and Metaphysics are used in a very vague and indefinite sense, to signify the investigation of all fundamental problems hearing on the ultimate origin, constitution, or end of things, and the nature of knowledge.
{3} Yet such a truncated exposition of the subject is almost unanimously adopted by English psychologists. Confer. A. Bain, {4} "The philosophic implications embedded in the very heart of psychology are not got rid of when they are kept out of sight. Some opinion regarding the nature of the mind and its relations to reality will show itself on almost every page, and the fact that this opinion is introduced without the conscious intention of the writer may serve to confuse both the author and his reader." (J. Dewey, Psychology, p. iv.) Höffding's work is a striking illustration of this. {5} Metaphysics Vol. I. p. 125.
{6} We have noticed only the most striking points of contrast. Strictly speaking, Logic is concerned for all truth -- physical, metaphysical, and moral. For a complete account of the province of Logic and its relations to the other sciences, see G. H. Joyce, S.J., Principles of Logic, c. i.
{7} The term positive science is frequently used to designate those branches of knowledge which deal with the laws of phenomena, facts observable by immediate experience. Some writers would confine the term science exclusively to this signification. Such usage is, however, illegitimate. The object of science is to discover causation; conequently, the inquiry into primary causes, which are properly the real causes, has a fortiori a right to this title. For the sake of precision, however, the term philosophical science may be conveniently employed to denote those branches of knowledge which deal not merely with secondary, but with the higher or primary causes. Rational Psychology is in this sense a philosophical science, as compared with the phenomenalistic or so-called positive sciences of Physiology and Empirical Psychology