A handbook of psychology

Preface To The Second Edition

In the preface to the first edition it was explained that " this handbook is designed primarily to introduce students to the science of psychology ; and to this design every other purpose, which the book may serve, has been made subordinate. Psychology embraces a considerable body of systems tised facts which are beyond dispute ; but there are also some problems, still unsettled, which affect even the fundamental principles of the science. No fair exposition of the science is possible without indicating the expositor's standpoint in reference to these problems ; but it is not advisable to perplex the beginner with a prefatory discussion of controverted questions ; and to the more advanced student, who may honour the book with a perusal, its general standpoint ought to be evident without preliminary explanations."

The original object of the book has been always kept in view in the present edition. Numerous alterations have been suggested on revision ; but these, though adding on the whole a few pages to the volume, are not individually of such importance as to require specific mention.

I may observe that, had I received Professor Ladd's Elements of Physiological Psychology in time, I should have referred to it at p. 12, as the best equivalent in English for the great German work of Wundt.

J. CLARK MURRAY.

Montreal, 16th April, 1888.

BOOK II.-S1ECIAL PSYCHOLOGY. Introduction, Part L— Cognitions

Chapter I.— Perception,

§ I. Perceptions of Taste,

§ 2. Perceptions of' Smell,

§ 3. Perceptions of Touch,

§ 4. Perceptions of Hearing,

§ 5. Perceptions of Sight,

§ 6. Muscular Perceptions,

Chapter II.— Generalisation § 1. Abstraction, § 2. Generalisation Proper, § 3. Denomination, -

Chapter III.— Reasoning, § 1. Conception, § 2. Judgment, § 3. Reasoning Proper, Contents. ix

Chapter IV. —Idealisation, § I. The Speculative Ideal; § 2. The ^Esthetic Ideal, § 3. The Ethical Ideal, § 4. The Religious Ideal,

Chapter V. — Illusory Cognitions, § 1, Illusions in General, • § 2. Dreaming, § 3. Hypnotic States,

Chapter VI.— General Nature of Knowledge, § 1. Self -consciousness, § 2. Time, .... § 3. Space, - § 4. Substance, - § 5. Cause, -

Part II.— Feelings, •

§ I. The nature of pleasure and pain, § 2. The expression of the feelings, § 3. Classification of the feelings, -

Chapter V. — Conclusion' . . - 43 1 PSYCHOLOGY

INTRODUCTION.

§ I. — Definition of Psychology,

PSYCHOLOGY* is the name now generally applied to the science which investigates the phenomena of the mind. Mind f is also denoted by the words soul and spirit^ while in mouein limes it has become common to use, as equivalent to these, certain expressions connected with the first personal pronoun, thrown into the form of substantives — the I, the me, the ego, the self. Another modern fashion in psychological language is to describe the mind by the term subject. The external world, when contrasted with mind or soul or spirit, is spoken of as matter or body ; it is opposed to the terms

* This name, though derived from ancient Greek, is of comparatively modern origin. It was used for the first time apparently during the sixteenth century, perhaps among the Ramists ; at least, Freigius is the earliest author, in whose writings it has been discovered. See Hamilton's Lectures on Metaphysics, Vol. i., pp. 135-6.

r On the history of the word mind a learned philological article by Mr. Earle will be found in Mind for July, 1881.

A expressive of the first person as the ncnego or notself % while the counterpart of subject is object In recent times mental phenomena are frequently distinguished from physical by the term psychical, — a term of some advantage from its being cognate with the name of the science.

The phenomena of the self or mind are distinguished from those of matter by a very marked characteristic. Any material thing whether organic or inorganic, whether at rest or in motion or undergoing any internal change, is wholly unaware of its own condition. It is not so with me. 1 may be ignorant oi innumerable actions and processes going on in my own body and in other bodies; but of what I myself do or suffer I must be cognisant, else it could not be said to be done or suffered by me. If I feel a pleasure or a pain, I must know that I feel it; and to deny my knowledge of the feeling would be to deny its existence. In like manner, when I see or hear, remember or imagine, believe or disbelieve, love or hate, I must know that I do so. Now, this knowledge of what is passing within me is called consciousness ; and it forms the distinctive attribute of the mind or self.

To avoid misapprehensions, it may be observed that we often speak of doing an action unconsciously. This seems to contradict the assertion that consciousness characterises all the actions we perform. But the truth is, that, when we use this expression, we mean that such an action is in reality done, not by oiirselves, but by those notselves, — those material things which we call our muscles, nerves, and brains. When a muscle twitches, or a nerve or brain-fibre thrills, without the movement being willed or intended by me, it is not I that produce the movement. It will be shown, in fact, that nervous and muscular actions often simulate strikingly the appearance of being originated and controlled intelligently by me, when, in reality, they are immediately due to habits of body formed long before by myself, or perhaps by my ancestors, or by the general constitution of nature. But an action, of which we are wholly unconscious, is one with which we have truly nothing to do, and that is the reason why we often exculpate ourselves by pleading that we acted unconsciously, inasmuch as the action could not then really have proceeded from us.

It follows from this, that, in speaking of the mind, we must avoid supposing it to be the brain or the heart or any other portion of the material thing we call our body. We sometimes, indeed, by a figure of speech, use brain and heart to mean mind or soul ; and the figure is allowable, so far as the inexact requirements of ordinary language are concerned. But, in scientific accuracy, " I " am not a brain, or heart, or system of nerves, or any part or the whole of a body.

It appears, then, that the distinctive characteristic 'of mind is, to be conscious of its phenomena ; and, consequently, these phenomena are often described as phenomena of consciousness. Like the phenomena of external nature, those of our internal consciousness will commonly be found to be composite, and therefore to require analysis. In order to such an analysis, it is necessary to know the elementary materials which enter into the composition of the phenomena analysed ; and accordingly the description of these materials will form the subject of the First Book of this work, which, as applying to all the phenomena of mind in general, may be appropriately styled General Psychology. The Second Book, to be distinguished as Special Psychology, will investigate the various combinations which form the special phases of our mental life.

Before proceeding to these subjects, some further introductory remarks may be found of service in reference to the method which should be adopted in the study of our science.

§ a. — Method of Psychology.

The method of Psychology is determined by the nature of the phenomena which it investigates. The nature of these phenomena, as we have seen, is that they are always accompanied by consciousness on the part of their subject. It is consequently by means of this accompanying consciousness, directed by proper precautions, that we must investigate the mind. The proper precautions, indeed, must not be neglected in Studying the phenomena of mind any more than in observing the phenomena of the material world ; for it cannot be su pposed that the ordinary consciousness of men will give them a scientific knowledge of what is passing in their minds more readily than their ordinary perceptions reveal the physical facts disclosed to the scientific observer. The precautions which the psychologist must adopt in order to direct and correct his observations, are not essentially different from those which must be taken by other scientific observers; they are rendered only more necessary inasmuch as nearly all the difficulties in the way of accurate observation are greatly enhanced by the peculiar character, especially by the extreme evanescence and complexity, of mental phenomena.

One of the most valuable safeguards against mistakes in observation is found by varying the circumstances in which phenomena are observed. Now this safeguard is readily supplied to the psychological observer by refusing to satisfy himself with the mere introspection of his individual mind, and endeavouring to watch the mental operations of others, as far as these are expressed in their language and external conduct. The study of psychology, by reflection on one's own conscious life, is sometimes spoken of as the Introspective or Subjective Method, by observations on the minds of others, as the Objective Method. Though some schools reject or unduly depreciate the former, it is evident that both methods must be combined ; for objective observations can be interpreted only by reference to the facts of our own consciousness.* In such observations it is important to seek the assistance of those studies which have for their object to inquire into the phenomena of human life that reflect the mental condition of men under every variety of external circumstances. The facts which reflect the mental life of man may do so either as being its product, or in so far as it is theirs. These it may be convenient to consider apart.

I. Of the phenomena which result from the action of the human mind, most have been already reduced to orderly study in separate sciences.

1. The main instrument which man employs for the expression of his conscious states is language, and there-

* Objective observations may sometimes usefully be extended to the mental life of the lower animals, which may occasionally throw light on the lower activities, at least, of the human mind ; but the interpretation of the actions of animals, as implying facts similar to those of our consciousness, cannot be accompanied with too great caution. For the student who wishes to follow out this line of inquiry, probably the most serviceable aids are the two works by Dr. G. J. Romanes on Animal Intelligenct and Mental Evolution i Animal*.

fore the Science of Language will be found of continual service to the psychologist ; for whether in the wide researches of comparative philology, or in the etymology of isolated words, the speech of men often reveals the history of ideas and feelings and mental habitudes, which could not otherwise be traced with so sure a step.

2. The origin of language is hidden in the trackless distance of a prehistoric past ; so also is the origin of society and of the system of life which society entails. But the actual condition of society, both in our own day and throughout historical periods, is within our reach ; and there are few more fascinating branches of study than that which investigates the picturesque varieties of moral standard, of social custom, of political institutions, by which human life is diversified under different climates and at different stages of civilisation. The accumulation of evidence on these subjects, especially in recent times, throws occasionally a welcome light, if not on the origin, at least on the development of many feelings and ideas and convictions, which play an important part in the human consciousness. The collection and preservation of accurate statistics with regard to the existing phenomena and the current changes of society, are becoming a serious work among all civilized nations ; and the facts thus obtained may often be consulted for evidence of the operation of great mental laws.

3. The studies, which have just been indicated, belong to what older writers, with some propriety, were wont to describe as the Natural History of Man. But the civil or political history of man, — what we understand by history simply, including, of course, biography, which is but the history of individuals — is not without its value to the psychologist, as revealing the mental influences by which human life receives its determinate character in any particular country at any particular time, as well as its development from age to age. In fact, the Philosophy of History must seek to bring the periods in the evolution of a nation, or in the vaster evolution of the human race, into harmony with the universal laws of the human mind.

4. But the phenomena, which most directly reflect the mental life of man, are the product of his mind in science and art. Science is evidently the systematic effort of human intelligence to unfold the intelligible order that exists throughout every realm of the universe ; and the evolution of scientific ideas must be an exponent of the laws which govern the evolution of man's general intelligence. In science the cool intellect alone is called into play ; in art the intellectual life is warmed with feeling. The fine arts, therefore, represent a double aspect of man's mental nature, — his power of knowing and his power of feeling. Accordingly the critical study of the fine arts, — of sculpture and painting, of music and literature, — will be found extremely serviceable in assisting to unravel some of the most complicated operations of the mind.

II. But the mind is not only a producer, it is also a product. It is true that the function of the mind is, by becoming conscious of the forces of nature, to free man from subjection to their unqualified sway. Still whatever freedom from the mere force of nature the mind may reach, there is another aspect in which it remains a natural product ; and in this aspect it receives an explanation in the agency of those natural forces by which it is modified.

1. Here the vast cosmic forces of the solar system may be practically left out of account, as their influence on the human mind is of an extremely remote and indirect character. The changes of summer and winter, of day and night, of morning and evening, as well as the varying phases of the moon, do exercise an appreciable influence over the thoughts and feelings of men. But the influence of these agencies in human life is not the irresistible domination of a natural force, such as they exert over vegetation, or over the life of migratory or hibernating animals; it is an influence which, in normal health, is completely under the control of intelligent volition, and grows tyrannical only when by disease life becomes helplessly subject to external nature.* It is true that the grandeur and mystery of the great cosmic movements have, in earlier times, exercised such a fascination over the human mind as to gain the credit of a direct influence on human life, the systematic interpretation of which formed the exploded science of astrology. But the general advance of human thought to the modern scientific point of view, is strikingly indicated when we contrast an antique astrological calculation on the effect of a man's "star" with the causal connection which recent observations have endeavoured to establish between the sun's spots and the social disasters which follow a famine.

2. Only less remote than the influences just described are those which have their origin in terrestrial nature, — the influences of a geographical, climatic, and meteorological character. Climate and geographical features have an undoubted power to mould the thoughts and feelings of men; but their effects in the history of the human mind have often been exaggerated by forgetting ar underestimating the energy of intelligence in asserting

• The belief at least in the tyranny of the moon over the diseased mind is preserved in the Latin lunaticus, the Greek <re\r)viaic6s, our English moonstruck, as well as the older expressions, tnoonish and moonling.

Introduction. g

itself over the force of its environment. Soil and climate and weather determine absolutely the life of animal and plant j but man succumbs to their influence only in proportion as disease reduces him to the condition of a mere animal organism, and thereby renders impossible the independent play of intelligence.

3. But in what is appropriately called human nature we come upon a region of the natural forces, which necessarily have a very direct influence in modifying the mental life of man. Among the powers of human nature some may be distinguished as universal from others which are particular,

i. By the former are meant of course those powers which are common to the whole of mankind. Now, some of these are extrinsic to the individual.

(a) The modifying influences here characterised as extrinsic to the individual are the race to which he belongs, and those general tendencies of his time which are sometimes spoken of as the Zeitgeist or spirit of the age. Amid the innumerable varieties by which human beings are distinguished, there are certain prevailing types, along which these varieties are ranged ; and such predominant types of variation may be traced in the mental as well as in the bodily characteristics. A type of this kind may often be referred to the common origin of the individuals in whom it predominates, and it then constitutes what we understand by a difference of race. It would be out of place, at this introductory stage, to discuss the explanation of race differences which may seem to be demanded by the present state of the science of man. It is sufficient to recognise the fact of the power which such differences are calculated to exert in shaping the character of a man's mind. But the influence of race is apt to be traversed by the influence of those mental tendencies that are characteristic of the period in which a man's life is passed. And it must not be forgotten that both influences are qualified by the principle already noticed, that the mind, being essentially intelligent of the forces of nature, may rise above their unconditional sway, and direct their operation.

(o) But this qualification is of less value when we come to those influences of human nature which are intrinsic to the individual. These are two : one being of a permanent character — sex ; another, of a mutable character — age. Even these agencies, however, are not absolutely irresistible in their effects. The freedom of the mind from the tyrannous sway of sex is seen in the manly courage which emergencies have sometimes called forth in women, and in the womanly tenderness often displayed by stern men. Such freedom may occasionally reach an extreme of excess ; a person may become " unsexed," though this cannot happen without a violation of human nature. Effeminacy in man, or masculine boldness in woman, are both unnatural monstrosities. In like manner the natural tendencies of age are also sometimes counteracted ; youth occasionally displays a scber thoughtfulness more characteristic of advanced life, while a happy juvenility of spirit is not infrequently carried down into a hale old age.

ii. But, besides the universal influences of race and sex and age, the human mind is subject to other influences that are particular, as they form the distinctive peculiarities of individuals.

(a) Sometimes these peculiarities are acquired in the course of the individual's life, and then they constitute his habits or character. Habit has been well named a second nature, for it acts in the same way as any tendency in the original nature of man. As habit is acquired, so it can also be overcome, or supplanted by an opposite tendency. In fact, all hope of intellectual and moral improvement rests on the power of reforming habits.

(b) But there is a less variable sphere of human nature — that of the tendencies which are born in the individual. These form what we express by the French naturel in the largest sense of the term, comprehending all that is commonly understood by genius in the intellectual sphere, and in the emotional by temperament or disposition.

The contact of man with the general system of forces in his own, as well as in external nature, depends on the fact that, in one aspect, he is an animal organism. The part of this organism, by which his conscious relations with nature are governed, is the system of nerves distributed throughout his body and centred in his brain. Accordingly, among the auxiliary studies, to which the psychologist resorts, the highest value must be attached to human anatomy and physiology, in so far as these explain the structure and functions of the different parts of the nervous system. It must not, indeed, be supposed, as has been too hastily assumed by some, that the physiology of the nervous system can enable us to dispense with that direct observation of consciousness, which is the special province of psychology. For even if the system of nerves in the human body were known much more perfectly than at present, no observation of it could ever reveal anything but material structures and processes ; no such observation could ever reveal the thoughts and feelings and volitions which make up our conscious life, or the laws by which these are governed. Still, it would be very unfortunate for the psychologist, were he unduly to depreciate the assistance which he may receive from the physiologist. It may now be accepted as a fact, that with every phenomenon of consciousness a corresponding phenomenon is set up in the nervous system ; and it will often be found that a knowledge of the nervous action is the most trustworthy guide to a psychological explanation of the phenomenon in consciousness, or the most efficient safeguard against mistakes about its nature. The student of psychology will, therefore, be materially assisted by seeking at least such acquaintance with physiology as may be obtained from Professor Huxley's Lessons in Elementary Physiology, or from works which treat especially of the physiology of the nervous system in its bearing on psychology, like Dr. Carpenter's Principles of Mental Physiology or the more elaborate Grundziige der Physiologischen Psychologie of Wundt. For the treatment of psychological questions in their connection with the evolutionism of the present day, the student should consult Spencer's Principles of Psychology \ which will be found of great value in other aspects as well.

Most of the other studies, which have been referred to in this section as tributary to psychology, are comprehended under anthropology in the widest conception of its range. The student, who is not familiar with the researches of this science, will find an interesting account of their drift, and an admirable preparation for more detailed study, in the Introduction to Anthropology, by Dr. E. B. Tylor.

BOOK I

GENERAL PSYCHOLOGY,

AN analysis of the phenomena of consciousness discovers the fact, that they are composed of certain simple factors, which may be regarded as the elements of our mental life, and that the combination of these elements is due to certain simple processes. Accordingly this Book divides itself naturally into two Parts, devoted respectively to the elements and the processes of mental life*

Tlu Elements of Mind. \?

PART I.

THE ELEMENTS OF MIND.

ELEMENTS are phenomena which are incapable of being decomposed ; and therefore the elements of mental life are those simple facts, beyond which science, in its last analysis of consciousness, has been unable to go. Such elementary , facts form merely what may be called the raw materials of mind ; they are wrought into actual mental states only as they are combined by the processes which will be afterwards explained. These raw materials of mind are connected by natural law with the great system of natural phenomena ; and the drift of the present investigation must be to trace that connection. In doing so we shall describe first the general nature of the mental elements, and then their specific forms.

CHAPTER L

THE GENERAL NATURE OF SENSATION.

THE natural elements, of which conscious life is formed, are the phenomena called sensti lions* A sensation is any consciousness arising from an action in the bodily organism. The organism, considered as endowed with the capacity of exciting consciousness, is said to be sensitive or sensible. The general capacity is spoken of as sensibility, and the particular forms of the sensibility are called senses. As sensation depends on the action of the bodily organism, it may be well, before examining the nature of sensation itself, to consider the structure of the organism, and the agencies by which its sensibility is excited.

§ i. — The Sensible Organism.

All bodies act and react on each other. Even the mineral is subject, not only to the mechanical impulse of bodies impinging on it, but occasionally also to chemical

* On the various meanings of the term sensation see Hamilton's edition of Reid's Works, p. 877, note. A history of theories in regard to sensation will be found in the same work, Note D, § 1.

alteration from bodies in affinity with it, and to thermal and electrical changes as well. The vegetable, and even the most rudimentary form of animal, exhibit the influence of foreign bodies by taking from them the constituents necessary for existence or growth, and restoring them after a period to the environment. But the higher animal organisms, and that of man especially, possess the power of responding in an innumerable variety of ways to surrounding agencies, and this responsive power is due mainly to the elaborate differentiation of the bodily organs in general, and more particularly of the nervous system.

It is sometimes said that the brain is the organ of mind. It would be more correct to say that the mind finds an organ, that is, an instrument, in the entire animal organism \ and this seems to be the explanation of the ancient doctrine, which, instead of restricting the soul to one part of the body, finds it " all in the whole, and all in every part." For the whole organism is, in every part, adapted to furnish materials for the building up of man's mental structure ; but it owes this adaptation to the elaborate system of nerves, with which every part is more or less completely supplied. The nervous system of man is two-fold : it consists of two systems, which are distinguished as the cerebrospinal and the sympathetic. The latter, by its distribution among the viscera, seems to be connected with the functions of organic life, rather than with those of the mind, though some hold it to be the special organ of the emotional nature.

The cerebro-spinal system, which certainly shows a vastly more intimate and complicated connection with mind, is divisible into two parts, — a central and a peripheral. The central portion is found in the brain and spinal cord. It is distinguishable to the eye by it?

greyish colour, and appears under the microscope to be formed by masses of minute vesicles or cells. The other portion, which connects the centres with the extremities, as well as the different centres with each other, is white in colour. It consists of strands of fibres, distributing themselves in ever minuter ramifications to every part of the organism. Among these fibres two groups may be distinguished as possessing distinct functions. One group, which issue from each side of the front of the spine, carry impulses from the centre outwards, and thereby stimulate muscular movement ; the other group, which issue from the back of the spine, transmit impulses inwards, and excite sensation. The nerves of sensation are, therefore, called afferent or centripetal ; those of motion, effcre?it or centrifugal. The body is thus seen to be the organ of the soul, not merely as the passive recipient of sensations excited by the action of external bodies, but as a source of energy by which it reacts on these and produces modifications in them.

The afferent nerves, which are thus distributed over the body, are perpetually carrying to the spinal cord and brain the impressions which have been excited in the various organs ; and these organs become thus the channels of different sensations. It is a moot point among physiologists, whether the specific differences of sensation are due to different nerves being endowed with different specific properties, or whether all nerves are identical in property, and become differentiated to different functions merely in consequence of the different uses to which they are put. This question, however, is of no essential moment to the psychologist ; for him it is sufficient, that specifically different sensations are awakened by the various alterations to which the different organs of the body are subject. But of course it is implied that a bodily organ can form the channel of sensation, only in so far as it is supplied with sentient nerve* fibres, and these arc- in uninterrupted connection with the brain. All the organs of the body are thus more or less sensitive ; but in respect of their sensibility a marked distinction may be drawn between two classes. For one set of organs are evidently by their very structure adapted mainly to the special function of producing sensation, and these are accordingly said to be the organs of the special senses ; while the other organs of the body give rise to sensation only incidentally, in performing the various functions of animal life, to which they are respectively adapted. But this is a distinction which can be conveniently explained only under the third section of this chapter, in the description of the various sensations we receive through the different organs.

§ 2. — Agencies which excite Sensibility.

The bodily organism, especially in consequence of its developed nervous system, is, as we have seen, responsive to the action of the various forces of nature ; and these forces may accordingly be spoken of in general as the agencies which excite sensation. Now, the action of these forces is conceived as some form of motion, whether it be the motion of masses of matter, or motion among the particles of which masses are composed. Consequently, the immediate stimulus of sensation may, in every case, be represented as some kind of movement. The movement may originate in the organism itself; for all the higher organisms are preserved and developed only by innumerable processes, which are apt to produce alterations of nervous tissue that may excite sensibility. In other cases, and these are more numerous, the movement originates in extraorganic bodies ; but it must always be translated into a nervous process before it can produce sensation.