In principle, then, introspection is very like inspection. The objects of observation are different; they are objects of dependent, not of independent experience; they are likely to be transient, elusive, slippery. Sometimes they refuse to be observed while they are in passage; they must be preserved in memory, as a delicate tissue is pre- 1 We discuss in § 69, where we are dealing with the elementary processes in emotion, the special difficulty mentioned above: that, if you concentrate your attention, say, upon your anger, the anger disappears. This difficulty makes it necessary to lay down special rules for the observation of emotion. But it does not make it necessary — and that is the point here ->- to observe emotion retrospectively.
24 Subject-matter, Method and Problem of Psychology served in hardening fluid, before they can be examined. And the standpoint of the observer is different; it is the standpoint of human life and of human interest, not of detachment and aloofness. But, in general, the method of psychology is much the same as the method of physics.
It must not be forgotten that, while the method of the physical and the psychological sciences is substantially the same, the subject-matter of these sciences is as different as it can well be. Ultimately, as we have seen, the subject-matter of all the sciences is the world of human experience; but we have also seen that the aspect of experience treated by physics is radically different from the aspect treated by psychology. The likeness of method may tempt us to slip from the one aspect to the other, as when a text- book of physics contains a chapter on vision and the sense of colour, or a text-book of physiology contains paragraphs on delu- sions of judgment; but this confusion of subject-matter must inevitably lead to confusion of thought. Since all the sciences are concerned with the one world of human experience, it is natural that scientific method, to whatever aspect of experience it is applied, should be in principle the same. On the other hand, when we have decided to examine some particular aspect of ex- perience, it is necessary that we hold fast to that aspect, and do not shift our point of view as the enquiry proceeds. Hence it is a great advantage that we have the two terms, introspection and inspection, to denote observation taken from the different standpoints of psychology and of physics. The use of the word intro- spection is a constant reminder that we are working in psychology, that we are observing the dependent aspect of the world of expe- rience.
Observation, as we said above, implies two things: attention to the phenomena, and record of the phenomena. The attention must be held at the highest possible degree of concentration; the record must be photographically accurate. Observation is, there- fore, both difficult and fatiguing; and introspection is, on the whole, more difficult and more fatiguing than inspection. To § y. The Scope of Psychology 25 secure reliable results, we must be strictly impartial and unpreju- diced, facing the facts as they come, ready to accept them as they are, not trying to fit them to any preconceived theory; and we must work only when our general disposition is favourable, when we are fresh and in good health, at ease in our surroundings, free from outside worry and anxiety. If these rules are not followed, no amount of experimenting will help us. The observer in the psychological laboratory is placed under the best possible external conditions; the room in which he works is fitted up and arranged in such a way that the observation may be repeated, that the process to be observed may stand out clearly upon the back- ground of consciousness, and that the factors in the process may be separately varied. But all this care is of no avail, unless the observer himself comes to the work in an even frame of mind, gives it his full attention, and is able adequately to translate his experience into words.
§ 7. The Scope of Psychology. — If mind is the sum- total of human experience considered as dependent upon the experiencing person, it follows that each one of us can have direct acquaintance only with a single mind, namely, with his own. We are concerned in psychology with the whole world of human experience; but we are concerned with it solely under its dependent aspect, as conditioned by a nervous system; and a nervous system is a particular thing, possessed by a particular individual. In strictness, therefore, it is only his own mind, the expe- rience dependent upon his own nervous system, that each of us knows at first-hand; it is only to this limited and in- dividual subject-matter that the method of experimental introspection can be directly applied. How, then, is a scientific psychology possible? How can psychology be anything more than a body of personal beliefs and indi- vidual opinions?
26 Subject-matter, Method and Problem of Psychology The difficulty is more apparent than real. We have every reason to believe, not only in general that our neigh- bours have minds like our own, that is, are able like our- selves to view experience in its dependent aspect, but also in detail that human minds resemble one another precisely as human bodies do. Within a given race there is much apparent diversity of outward form: differences in height and figure, in colour of hair and eyes, in shape of nose and mouth. We notice these differences, because we are obliged in everyday life to distinguish the persons with whom we come in contact. But the resemblances are more fundamental than the differences. If we have recourse to exact measurements, we find that there is in every case a certain standard or type to which the indi- vidual more or less closely conforms and about which all the individuals are more or less closely grouped. And even without measurement we have evidence to the same effect: strangers see family likenesses which the mem- bers of the family cannot themselves detect, and the units in a crowd of aliens, Chinese or Negroes, look bewilder- ingly alike.
Now all of our main social institutions rest upon the as- sumption that the individuals of whom society is com- posed possess minds, and possess minds that are of the same sort. Language, religion, law and custom, — they one and all rest upon this assumption, and they one and all bear testimony that the assumption is well grounded. Would a man invent language in order to talk to himself? Language implies that there are more minds than one. And would the use of a common speech be possible if minds were not essentially alike? Men differ in their command of language, as they differ in complexion, or in § y. The Scope of Psychology 27 liability to disease; but the general use of language testifies to a fundamental likeness of mental constitution in us all.
Hence the psychologist is fully justified in believing that other men have minds of the same kind as his own, and in basing psychology upon the introspective reports furnished by a number of different observers. These reports show, in point of fact, just what we should expect them to show: a fundamental agreement, and a great variety of detail, — the mental differences grouping them- selves, as we have seen that physical differences group themselves, about a central type or standard.
If, however, we attribute minds to other human beings, // we have no right to deny them to the higher animalsi' These animals are provided with a nervous system of the same pattern as ours, and their conduct or behaviour, under circumstances that would arouse certain feelings in us, often seems to express, quite definitely, similar feelings in them. Surely we must grant that the highest verte- brates, mammals and birds, have minds. But the lower vertebrates, fishes and reptiles and amphibia, possess a nervous system of the same order, although of simpler construction. And many of the invertebrates, insects and spiders and crustaceans, show a fairly high degree of nervous development. Indeed, it is difficult to limit mind to the animals that possess even a rudimentary ner- vous system; for the creatures that rank still lower in the scale of life manage to do, without a nervous system, practically everything that their superiors do by its assist- ance. The range of mind thus appears to be as wide as the range of animal life.
The plants, on the other hand, appear to be mindless. Many of them are endowed with what we may term sense-organs, that is, 28 Subject-matter^ Method and Problem of Psychology organs differentiated to receive certain forms of stimulus, pressure, impact, light, etc. These organs are analogous in structure to the sense-organs of the lower animal organisms: thus, plant ' eyes ' have been found, which closely resemble rudimentary animal eyes, and which — -if they belonged to animals — might mediate the perception of light: so that the development of the plant-world has evidently been governed by the same general laws of adapta- tion to environment that have been at work in the animal king- dom. But we have no evidence of a plant-consciousness.
Just as the scope of psychology extends beyond man to the animals, so does it extend from the individual man to groups of men, to societies. The subject-matter of psy- chology is human experience considered as dependent upon the individual. But since the individuals of the same race and epoch are organised in much the same way, and since they live together in a society where their conduct affects and is affected by the conduct of others, their view of experience under its dependent aspect natu- rally becomes, in certain main features, a common or general view; and this common view is embodied in those social institutions to which we have referred above, — in language, religion, law and custom. There is no such thing as a collective mind, or a national mind, or a social mind, if we mean by mind some immaterial being; but there is a collective mind, if we mean by it the sum-total of human experience considered as dependent upon a social group of similar individuals. The study of the collective mind gives us a psychology of language, a psychology of myth, a psychology of custom, etc.; it also gives us a differential psychology of the Latin mind, of the Anglo-Saxon mind, of the Oriental mind, etc.
And this is not all: the scope of psychology extends, § 7- The Scope of Psychology 29 still further, from the normal to the abnormal mind. Life, as we know, need not be either complete or completely- healthy life. The living organism may show defect, the lack of a limb or of a sense-organ; and it may show dis- order and disease, a temporary or a permanent lapse from health. So it is with mind. The consciousnesses of those who are born deaf or blind are defective; they lack certain sensations and images that are normally present. In dreaming and the hypnotic state, during intoxication, after prolonged sleeplessness or severe strain of any kind, we have illustrations of temporary mental derangement. And the various forms of insanity — mania, melancholia, demen- tia — are forms of permanent mental disorder.
Derangement of the social mind may be studied in the various panics, fads, epidemics of speculation, of false belief, etc., which occur from time to time even in the most highly civilised societies. The mob consciousness stands to a healthy social consciousness very much as dreaming to the waking life. Permanent disorder of the social mind means the downfall of society.
All these various fields of psychology may be cultivated for their own sake, on account of their intrinsic interest and value; they must, indeed, be so cultivated, if psychology is to progress. At the same time, their facts and laws often throw light upon the problems of normal human psychology. Suppose, for instance, that a man, blind from his birth, is rendered able to see by a surgical operation. He must learn to use his eyes, as a child learns to walk. And the gradual perfecting of his vision, the mistakes and confusions to which he is liable, all the details of his visual education, form a storehouse of facts upon which the psychologist can draw when he seeks to illustrate the development of the perception of space in the normal mind, — the manner in which we come to judge of the distance of objects from ourselves 30 Subject-matter, Method and Problem of Psychology and from one another, of their direction, and of their size and shape. Instructive, also, are those forms of mental unsoundness which consist in the derangement of a single group of processes. The various types of morbid fear — agoraphobia, the fear of being alone in open spaces; neophobia, the fear of everything that is new; phobophobia, the nervous dread of being afraid — are only exaggerated forms of experiences that most of us have had. The sanest man will feel lost when he passes, suddenly, from a quiet country life to the bustle of a large town; we are all a little timid when we enter a strange community; we have all been afraid that on such-and-such an occasion we shall show our nervousness. Similarly, the self-importance of paranoia is merely an exaggeration of the pleased self-consciousness, the self-complacency, that we often observe in others and, if we are honest, must often detect in ourselves. In all these instances, the strong lines of the caricature may help us to a more correct picture of the normal consciousness.
§ 8. The Use of Analogy in Psychology. — We have agreed that the psychologist is not confined to a knowledge of his own mind. Although this is the only mind to which he can directly apply the method of experimental intro- spection, he can apply the method indirectly to any num- ber of minds. Psychology is based upon the introspections of a large number of trained observers.
But we have gone much farther than this. We have spoken of an animal psychology, a social psychology, and a psychology of the abnormal mind. What, then, is the method to be employed in these branches of psychology? We cannot ask the animal or the society or the madman to introspect!
Yet, in a sense, this is just what we do. Observation, it will be remembered, implies two things: attention to the phenomena, and record of the phenomena. We § 8. The Use of Analogy in Psychology 31 ourselves record mental phenomena, for psychological purposes, in language. This form of record has great advantages: it is flexible, since we have a large vocabu- lary at our disposal; it is constant, since written or printed reports may be preserved for a long time; and it is easily intelligible, since we are accustomed to the use of words in everyday life. At the same time, language is not the only possible means of expression. Physically regarded, it is a complex bodily movement: spoken lan- guage is a movement of the larynx, written language a movement of the hand: and it belongs to the class of movements that we term gestures. We can express our ideas by a grimace or a shrug of the shoulders, as well as by spoken words or a written paragraph.
Now the psychologist argues, by analogy, that what holds of himself holds also, in principle, of the animal, of society, and of the insane. He argues that the move- ments of animals are, to a large extent, gestures; that they express or record the animal's mental processes. He therefore tries, so far as possible, to put himself in the place of the animal, to find the conditions under which his own movements would be of the same general kind; and then, from the character of his human consciousness, he attempts — always bearing in mind the limit of de- velopment of the animal's nervous system — to recon- struct the animal consciousness. He calls experiment to his assistance, and places the animal in circumstances which permit of the repetition, isolation and variation of certain types of movement or behaviour. The animal is thus made, so to say, to observe, to introspect; it attends to certain stimuli, and registers its experience by gesture. Of course, this is not scientific observation: science, as 32 Subject-matter, Metliod and Problem of Psychology we said in § I, implies a definite attitude to the world of experience, and consists in a description of the world as viewed from a definite standpoint. None the less, it is observation, and as such furnishes raw material for science. The psychologist works the raw material into shape; he observes the gesture, and transcribes the ani- mal consciousness in the light of his own introspection.
Roundabout as this method appears, it has nevertheless led, in the hands of skilled investigators, to perfectly definite results. And it is by way of detailed investigation, and by that way only, that the general questions of animal psychology can be finally answered. One of these questions is that of the ' criterion of mind.' How are we to decide whether the animal before us does or does not possess mind? How are we to decide whether it has attended to the stimulus, so that its movement is a gesture movement, or whether it has received the stimulus mindlessly and mechanically, so that the movement is a reflex? An answer now commonly given to this question is that we may assume the presence of mind wherever the animal rapidly adjusts itself to new conditions, quickly learns to get its bearings in a novel environment. The answer is, of course, based upon the analogy of human experience. It is, however, unwise to commit oneself to a criterion of this nature. What is needed is an exhaustive study of all the various modes in which animals do, as a matter of fact, adjust themselves to new conditions. Then the criterion of mind will appear, so to speak, of its own accord.
Another general question is that of the interpretation of the animal consciousness. Shall we assume that this consciousness is always as simple as possible? Or shall we give the animal the benefit of our doubt, take its different forms of behaviour at their face value, and ascribe to it processes of memory, of idea- tion, of reasoning, that differ from our own only in degree? On this question opinion is sharply divided. Both positions may be supported by the analogy of the human consciousness, since this may be, under very similar circumstances, either extremely com- § 8. The Use of Analogy in Psychology 33 plex or surprisingly simple. And so we find one authority laying it down that " in no case may we interpret an action as the out- come of the exercise of a higher psychical faculty, if it can be interpreted as the outcome of the exercise of one which stands lower in the psychological scale";1 while another authority de- clares that "we are too ready to adopt simple — unduly simple — explanations of the animals by which we are surrounded." 2 It is, again, unwise to commit oneself to either view. The animal must be subjected to experimental test, under conditions of gradually increasing complexity, and we must find out by actual trial how far it is able to cope with these conditions. Then our principles of interpretation will, also, emerge of their own ac- cord.— We do, then, make the animals attend to stimuli and report their experiences to us; we do, after a fashion, make them in- trospect. This would be impossible if introspection implied a reflective attitude towards mind, or a special kind of mental awareness of mental processes. But, as we have seen, intro- spection is simply observation of dependent experience: it is therefore precisely the sort of observation that an animal can make, if it has a mind at all. Our own task is to do what the animals cannot do: to systematise and interpret the observations in terms of human consciousness.
What holds of the study of the animal mind holds also of social psychology. The introspections made in com- mon by the members of a social group are recorded for us in the forms of speech, in custom and law, in myth and religion. Society has introspected, and has recorded its introspections in these various institutions. It is, ob- viously, impossible for the psychologist to experiment upon the social mind in any direct way. It is therefore fortunate that nature has made experiments for him. By 1 C. L. Morgan, An Introduction to Comparative Psychology, 1894, 53..
2 W. Mills, The Nature and Development of Animal Intelligence, 1898, 12, D 34 Subject-matter, MetJiod and Problem of Psychology comparing the languages, customs, etc., of different types of human society at all the different levels of human evo- lution, he is able to repeat, isolate and vary his observa- tions; history furnishes him with a laboratory of social psychology.
It is clear that the study of social psychology requires the use of analogy. It is we, the moderns, who study the myths and customs of primitive man, and we have to psychologise these myths and customs from our own modern standpoint. Hence it is natural to find, in works upon the subject, the same sort of disagreement on general principles that we have noted in the case of animal psychology. And the remedy is the same. We must not hastily adopt a particular view of human evolution, but must patiently examine all the available records; must seek to add to the records by researches among the lower races of mankind; and must then accept the general principles that an exhaustive survey of the facts suggests to us.
Since social psychology is thus a genetic study, a study of human development, it has become customary to speak of its method as a genetic method. In strictness, however, there is no such thing as a genetic method. There is a genetic point of view, as there is a static point of view. We may be interested in the sequence of mental processes, in tracing the course of mind from simple to complex; or we may be interested in the coexistence of mental processes, in unravelling the tangle of a special sort of consciousness. But the difference of interest does not mean a difference of method.
For the psychology of dreaming and of intoxication we have the advantage of direct introspective records. We may also have recourse to experiment. A sleeping person, for example, may be subjected to various kinds of stimu- lation, and may be aroused, after the stimuli have been applied, to give an account of the dream which they oc- casioned.
§ 8. The Use of Analogy in Psychology 35 The psychological study of hypnosis is less direct, since the hypnotic subject usually forgets, on arousal, what has taken place during the hypnotic state. We must therefore observe his behaviour during hypnosis, taking care to make our tests as simple and straightforward as possible, and must then seek to reconstruct the hypnotic conscious- ness on the analogy of the normal waking consciousness. It is, of course, possible to secure introspective reports from hypnotic subjects; but it is still a matter of dispute whether these reports are true records of observations, or do not rather reflect the ideas and opinions of those who are conducting the experiment. The hypnotic subject is extremely suggestible; that is to say, he is exceedingly liable to pick up a hint from the experimenter, and to report as he thinks the experimenter desires or expects him to report.
For the study of the insane mind, we have, in the first place, the utterances and behaviour of insane persons. We have also the opportunity to experiment; the inmates of hospitals may be subjected to systematic tests, the results of which will give us an insight into their mental processes. So far, this branch of psychology is in a back- ward condition, since we have been more concerned to shelter and, if possible, to cure the insane than to de- scribe the insane consciousness. Certain forms of in- sanity are, however, of great psychological interest, and we may look confidently to a realisation of this interest in the near future. — After all, therefore, it is not so absurd as at first thought it seems, to say that we require the animal and society and the madman to introspect. All three may attend; all three may report their experiences. The attention is 36 Subject-matter, MetJiod and Problem of Psyclwlogy likely to be partial, fitful, roving, and the report is likely to be transient, equivocal, imperfect; and so we are com- pelled, in all three cases, to fall back upon the analogy of our own consciousness. In other words, it is entirely possible to work out, by psychological method, a psy- chology of the animal, of the social, and of the unsound mind, but it is also very difficult: the psychologist is ex- posed, at every moment, to the danger of misinterpreta- tion. However, here as elsewhere in science, the pursuit of knowledge furnishes its own corrective. Sooner or later the unfit hypothesis breaks down in face of newly discovered facts.
§ 9. The Problem of Psychology. — Science seeks always to answer three questions in regard to its subject-matter, the questions of what, how, and why. What precisely, stripped of all complications and reduced to its lowest terms, is this subject-matter? How, then, does it come to appear as it does; how are its elements combined and arranged? And, finally, why does it appear now in just this particular combination or arrangement? All three questions must be answered, if we are to have a science that shall satisfy the definition of § 1.
It is often said that the answers to the questions ' what ' and ' how ' give us a description, the answer to the question ' why ' an explanation, of the facts with which science deals. This distinc- tion is useful, if we do not make it too rigid. It would be a grave mistake to suppose, for instance, that we may first of all work out an exhaustive description of the world, and then proceed delib- erately to explain what we have already described. On the con- trary, knowledge grows by a constant give and take between description and explanation; we describe in terms of some theory, that is, in terms of some tentative explanation, and then we rectify § 9- The Problem of Psychology 37 our theory in the light of the observed facts; and so on, over and over again. The distinction is thus logical only; it does not point to two successive stages in the history of the special sciences.
To answer the question ' what ' is the task of analysis. Physical science, for example, tries by analysis to reduce the world of independent experience to its lowest terms, and so arrives at the various chemical elements. To answer the question ' how ' is the task of synthesis. Physical science traces the behaviour of the elements in their various combinations, and presently succeeds in formulating the laws of nature. When these two ques- tions have been answered, we have a description of physi- cal phenomena. But science enquires, further, why a given set of phenomena occurs in just this given way, and not otherwise; and it answers the question ' why ' by laying bare the cause of which the observed phenomena are the effect. There was dew on the ground last night because the surface of the earth was colder than the layer of air above it; dew forms on glass and not on metal because the radiating power of the one is great and of the other is small. When the cause of a physical phe- nomenon has thus been assigned, the phenomenon is said to be explained.
So far, now, as description is concerned, the problem of psychology closely resembles the problem of physics. The psychologist seeks, first of all, to analyse mental experience into its simplest components. He takes a par- ticular consciousness and works over it again and again, phase by phase and process by process, until his analysis can go no further. He is left with certain mental pro- cesses which resist analysis, which are absolutely simple in 38 Subject-matter, Method and Prod/em of Psychology