8 Subject-matter, Method and Problem of Psychology gives us facts and laws of physics; our second gives us facts and laws of psychology.
Now take three other topics that are discussed in the physical text-books: heat, sound and light. Heat proper, the physicists tell us, is the energy of molecular motion; that is to say, heat is a form of energy due to a movement of the particles of a body among themselves. Radiant heat belongs, with light, to what is called radiant energy, — energy that is propagated by wave-movements of the luminiferous ether with which space is filled. Sound is a form of energy due to the vibratory movements of bodies, and is propagated by wave-movements of some elastic medium, solid, liquid or gaseous. In brief, heat is a dance of molecules; light is a wave-motion of the ether; sound is a wave-motion of the air. The world of physics, in which these types of experience are considered as inde- pendent of the experiencing person, is neither warm nor cold, neither dark nor light, neither silent nor noisy. It is only when the experiences are considered as dependent upon some person that we have warmth and cold, blacks and whites and colours and greys, tones and hisses and thuds. And these things are subject-matter of psy- chology.
We find, then, a great difference in the aspect of experi- ence, according as it is viewed from the one or the other of our different standpoints. It is the same experience all through; physics and psychology deal with the same stuff, the same material; the sciences are separated simply — and sufficiently — by their point of view. From the stand- point of physics, we get such sciences as physics (in the narrower sense), chemistry, geology, astronomy, meteo- rology. From the standpoint of psychology we get, in the § 3- The Common-sense View of Mind 9 same way, a special group of sciences: their names and provinces are given in § 7.
It must be clearly understood that we are not here attempting to give a strict definition of the subject-matter of psychology. We assume that everybody knows, at first hand, what human experience is, and we then seek to mark off the two aspects of this experience which are dealt with respectively by physics and psychology. Any further definition of the subject-matter of psychology is impossible. Unless one knows, by experience itself, what experience is, one can no more give a meaning to the term ' mind ' than a stone can give a meaning to the term ' matter.'
§ 3. The Common-sense View of Mind. — If, before you read the two preceding sections, you had been asked to define psychology, you would probably have said, without hesitation, that it is the science of mind. But you would have meant by mind something that, at all events in appearance, is very different from the meaning that these two sections have given it. Let us see how nearly we can reconcile the common-sense idea of mind with the view that it is the sum -total of human experience considered as dependent upon the experiencing person.
The common-sense idea of the world is roughly this. The world is made up of, or contains, two radically differ- ent things: matter and mind. Matter is found in the physical objects around us; it always fills space; it is gov- erned by mechanical laws, laws of cause and effect. Mind is found in ourselves and, very likely, in some of the other animals; it is immaterial, not spatial; it is not bound by mechanical laws, but is free to act as it will; if it submits to laws at all (as, for instance, to the laws of thought in our processes of reasoning), these are laws peculiar to it, and are not the same as the laws of nature. Nevertheless, 10 Subject-matter, Method and Problem of Psychology different as mind and matter are, they are joined together, in a very intimate way, both in ourselves and in such of the animals as possess minds; for our physical bodies are material. And when they are thus joined together, they act upon each other, mind affecting matter and matter affecting mind. We cry because we are grieved; we can- not think clearly because we have eaten too heavy a dinner. Compare these statements, now, with the statements of §§ i and 2. Common sense declares that mind and matter are radically different. We have said that, in order to get the subject-matter of physics and of psychology, one must regard human experience from standpoints as diverse as can be found. So far there is a general agreement. Com- mon sense declares that the laws of matter are different from the laws of mind. We have seen that, for instance, space, time and mass behave very differently, according as they are taken to be independent of, or dependent upon, the experiencing person. Again there is agreement. Com- mon sense declares that we, and perhaps the animals, are made up both of matter and of mind. Here also, if we go beneath the difference of terms, there is agreement. The living body, as it is treated in the science of physiology, is treated from the physical point of view; it belongs to the independent aspect of experience. The same living body -that is to say, an organism, an organised individual — is, however, precisely the 'experiencing person' referred to in our definition of mind. It is when heat-waves strike the skin, and sound-waves strike the ear, and light-waves strike the eye, that we have experience in its dependent aspect, as warmth and tone and colour. On these three points, therefore, we have no serious quarrel with common sense. On the other hand, common sense makes certain other statements that we cannot accept. These statements all point to a view of mind which is not often expressed out- right, in so many words, but which is very generally held: the view, namely, that mind is a living being, with all the qualities and powers that are possessed by material living beings; an immaterial animal, so to say, that dwells within the material animal; an inward man, manifesting itself in the behaviour of the outward man. A mind so conceived cannot fill space, because it is not material; but it has all the other properties of a living creature. It is free to act as it pleases, just as you are free to come or to go, to do this or to do that. It can influence the body, and be influenced by the body, just as you may influence or be influenced by your friend. This view of mind probably appears natural enough, although, as soon as you begin to ask questions, you will find that it is by no means clear. Natural or not, however, it is a view which we must here reject, for the following reasons.
(i) A statement that rests upon common sense is not likely to be argued; it is taken for granted, as something that needs no discussion. Yet, in theoretical matters, common sense is an unsafe guide. For the common sense of our own generation simply sums up so much of the advanced thought of former generations as the great body of mankind has found acceptable and intelligible. A brilliant speculation of one age may become the com- mon sense of the next: but this does not make it any the less speculation, while in the course of becoming common sense its logical structure has, inevitably, been more or less damaged. Common sense, in theoretical matters, is past philosophy; and the philosophy is the more vulgar ised, the farther it has travelled from its source.
12 Subject-matter, Method and Problem of Psychology There is no dispute as to the philosophical source from which, in the present instance, our common-sense ideas are derived. The view of mind and matter which we are now criticising was set forth, in all essential points, by the French philosopher, Rene Descartes (i 596-1650). Nr> doubt, the common-sense version has certain crude ele ments which are indefinitely older than Descartes; no doubt, also, it has been tinged by later thought, notably by the doctrine of organic evolution. In the main, how- ever, what is common sense to-day was high Cartesian philosophy two centuries and a half ago.1 Plainly, then, we cannot take common sense for granted. As we should not nowadays pin our philosophical faith to Descartes, so we cannot leave Cartesian doctrines un- questioned when they appear in the garb of common sense. We shall rather expect to find that Descartes, and with him our own common sense, are partly right and partly wrong.
(2) That some of the doctrines of common sense agree, in general, with the position of §§ 1 and 2 has already been shown. The remainder must be rejected, because the evidence is against them. We are told that mind is not spatial: yet, as Fig. 1 shows, mental experience takes on the spatial form as readily as physical experience. We are told that mind is free to act as it pleases: yet, as we shall see in this book, the more carefully mind is stud- ied, the more plainly are the laws of mental experience revealed. We are told that mind influences body, and ' You will find that this statement is borne out by the histories of philoso- phy. Turn, for instant e, to A. K. Rogers, / Student's History of Philosophy, 1901, pp. 269 289, espei ially 284-287. The passage is not easy reading- hut you will understand it well enough to see that what is said in the text is historically correct.
body mind. How an immaterial thing can influence and be influenced by a material thing we are not told, — for the very good reason that nobody knows: though, if this were the only view that did justice to the facts, we should nevertheless be bound to accept it. Since, as the follow- ing section shows, all the observed facts can be rationally explained from the standpoint of §§ 1 and 2, this stand- point must be preferred.
§ 4. Psychophysical Parallelism. — Common sense says that we cry because we are sorry, laugh because we are amused, run because we are frightened; that we feel gloomy and morose because we do not digest our food, go insane from softening of the brain, lose consciousness because we have inhaled ether. Mind influences body, and body influences mind. Our own position has been that mind and body, the subject-matter of psychology and the subject-matter of physiology, are simply two aspects of the same world of experience. They cannot influence each other, because they are not separate and independent things. For the same reason, however, wherever the two aspects appear, any change that occurs in the one will be accompanied by a corresponding change in the other. Your view of a town from the east cannot influence your view of the same town from the west; but as your view from the east differs in sunlight and moonlight, so corre- spondingly will your view from the west differ. This doctrine of the relation of mind to body is known as the doctrine of psychophysical parallelism: the common- sense doctrine is that of interaction.
From the point of view of psychophysical parallelism, then, it is not strictly true to say that we cry because we 14 Subject-matter, Method and Problem of Psychology are sorry. If we look at the whole experience under its independent aspect, we find that certain physical events certain stimuli, affect the body; they set up in the body, and especially in the nervous system, certain physical changes; these changes cause the secretion of tears. This is an exhaustive account of the experience, considered as independent of the experiencing person. If we look at the experience under its dependent aspect, we find that our consciousness has been invaded by grief or remorse or some kindred emotion. The two sets of events, physical and mental, are parallel, but they do not interfere with each other. And the same thing holds of all the other cases cited at the beginning of this section.
By accepting this doctrine of parallelism we gain a two- fold advantage. On the positive side, we are able to do justice to all the observed facts; we never come into con- tradiction with facts. On the negative side, we avoid per- plexing questions, questions that lead nowhere because they are put from a wrong standpoint. The common- sense view of mind appears natural; but as soon as you ask questions, you find it obscure. Where, for in- stance, on that view, does the body end and the mind begin? Do the senses belong to mind or to body? Is the mind always active and the body always passive? Do body and mind ever act independently of each other? Ques- tions such as these arise at once; but it is a hard matter to answer them. Parallelism has no logical pitfalls of this kind.
At the same time, we need not be pedantic, and change our manner of speech to accord with the strict letter of parallelism. The astronomer does not scruple to talk, with all the rest of us, about sunrise and sunset. It is not strictly § 5- Mental Process y Consciousness and Mind 15 true to say that we cry because we are sorry; our crying is the effect of certain nervous (that is, physical) changes, whose parallel on the mental side is the emotion of grief. But this parallel is constant and invariable. We should not cry, under the circumstances, unless we were sorry, because our sorrow is the mental aspect of those nervous changes that make us cry: we have only to shift our point of view, and what appeared as nervous change appears as emotion. So that, for all practical purposes, it is true to say that we cry because we are sorry, and run because we are frightened, and so forth. What we have to guard against is not the phrasing of these statements, but their popular interpretation. To suppose that the sorrow and the fear are literally the cause of tears and bodily move- ments would be on a par with supposing that the idea of watering the lawn can, literally and directly, turn the tap and set the sprinkler in motion.
§ 5. Mental Process, Consciousness and Mind. — The most striking fact about the world of human experience is the fact of change. Nothing stands still; everything goes on. The sun will someday lose its heat; the eternal hills are, little by little, breaking up and wearing away. Whatever we observe, and from whatever standpoint we observe it, we find process, occurrence; nowhere is there permanence or stability. Mankind, it is true, has sought to arrest this flux, and to give stability to the world of experience, by assuming two permanent substances, matter and mind: the occurrences of the physical world are then supposed to be manifestations of matter, and the occurrences of the mental world to be manifestations of mind. Such an hypothesis may be of value at a certain stage of human 1 6 Subject-matter, Method and Problem of Psychology thought; but every hypothesis that does not accord with the facts must, sooner or later, be given up. Physicists are therefore giving up the hypothesis of an unchanging, substantial matter, and psychologists are giving up the hypothesis of an unchanging, substantial mind. Stable objects and substantial things belong, not to the world of science, physical or psychological, but only to the world of common sense.
We have defined mind as the sum-total of human experi- ence considered as dependent upon the experiencing person. We have said, further, that the phrase ' experiencing per- son ' means the living body, the organised individual; and we have hinted that, for psychological purposes, the living body may be reduced to the nervous system and its attach- ments. Mind thus becomes the sum-total of human experi- ence considered as dependent upon a nervous system. And since human experience is always process, occurrence, and the dependent aspect of human experience is its mental aspect, we may say, more shortly, that mind is the sum- total of mental processes. All these words are significant. ' Sum-total ' implies that we are concerned with the whole world of experience, not with a limited portion of it; ' men- tal ' implies that we are concerned with experience under its dependent aspect, as conditioned by a nervous system; and' processes ' implies that our subject-matter is a stream, a perpetual flux, and not a collection of unchanging objects.
It is not easy, even with the best will possible, to shift from the common-sense to the scientific view of mind; the change can- not be made all in a moment. We are to regard mind as a stream of processes? But mind is personal, my mind; and my person- ality continues throughout my life. The experiencing person is only the bodily organism? But, again, experience is personal, the § 5« Menial Process, Consciousness and Mind \"j experience of a permanent self. Mind is spatial, just as matter is? But mind is invisible, intangible; it is not here or there, square or round.
These objections cannot be finally met until we have gone some distance into psychology, and can see how the scientific view of mind works out. Even now, however, they will weaken as you look at them. Face that question of personality. Is your life, as a matter of fact, always personal? Do you not, time and again, forget yourself, lose yourself, disregard yourself, neglect yourself, contradict yourself, in a very literal sense? Surely, the mental life is only intermittently personal. And is your personality, when it is realised, unchanging? Are you the same self in childhood and manhood, in your working and in your playing moods, when you are on your best behaviour and when you are freed from restraint? Surely, the self-experience is not only intermittent, but also com- posed, at different times, of very different factors. As to the other question: mind is, of course, invisible, because sight is mind; and mind is intangible, because touch is mind. Sight-experience and touch-experience are dependent upon the experiencing person. But common sense itself bears witness, against its own belief, to the fact that mind is spatial: we speak, and speak correctly, of an idea in our head, a pain in our foot. And if the idea is the idea of a circle seen in the mind's eye, it is round; and if it is the visual idea of a square, it is square.
Consciousness, as reference to any dictionary will show, is a term that has many meanings. Here it is, perhaps, enough to distinguish two principal uses of the word.
In its first sense, consciousness means the mind's awareness of its own processes. Just as, from the common- sense point of view, mind is that inner self which thinks, remembers, chooses, reasons, directs the movements of the body, so is consciousness the inner knowledge of this thought and government. You are conscious of the correctness of your answer to an examination question, of c 1 8 Subject-matter, Method and Problem of Psychology the awkwardness of your movements, of the purity of your motives. Consciousness is thus something more than mind; it is " the perception of what passes in a man's own mind "; 1 it is " the immediate knowledge which the mind has of its sensations and thoughts."2 In its second sense, consciousness is identified with mind, and ' conscious ' with ' mental.' So long as mental processes are going on, consciousness is present; as soon as mental processes are in abeyance, unconsciousness sets in. " To say I am conscious of a feeling, is merely to say that I feel it. To have a feeling is to be conscious; and to be conscious is to have a feeling. To be conscious of the prick of the pin, is merely to have the sensation. And though I have these various modes of naming my sensa- tion, by saying, I feel the prick of a pin, I feel the pain of a prick, I have the sensation of a prick, I have the feeling of a prick, I am conscious of the feeling; the thing named in all these various ways is one and the same." 3 The first of these definitions we must reject. It is not only unnecessary, but it is also misleading, to speak of consciousness as the mind's awareness of itself. The usage is unnecessary, because, as we shall see later, this awareness is a matter of observation of the same general kind as observation of the external world; it is mislead- ing, because it suggests that mind is a personal being, instead of a stream of processes. We shall therefore 1 John Locke, An Essay Concerning Human Understanding, [1690] Bk.
- Dugald Stewart, Outlines of Moral Philosophy, [1793] Pt. I., Section i., 8 James Mill, Analysis of the Phenomena of the Human Mind, [1829] Vol. I., Ch. v. Mill uses the word 'feeling' to denote what we have called 'mental process.'
§ 6. The Method of Psychology 19 take mind and consciousness to mean the same thing. But as we have the two different words, and it is convenient to make some distinction between them, we shall speak of mind when we mean the sum-total of mental processes occurring in the life -time of an individual, and we shall speak of consciousness when we mean the sum-total of mental processes occurring now, at any given ' present ' time. Consciousness will thus be a section, a division, of the mind-stream. This distinction is, indeed, already made in common speech: when we say that a man has ' lost consciousness,' we mean that the lapse is temporary, that the mental life will shortly be resumed; when we say that a man has ' lost his mind,' we mean — not, it is true, that mind has altogether disappeared, but certainly that the derangement is permanent and chronic.
While, therefore, the subject-matter of psychology is mind, the direct object of psychological study is always a consciousness. In strictness, we can never observe the same consciousness twice over; the stream of mind flows on, never to return. Practically, we can observe a par- ticular consciousness as often as we wish, since mental processes group themselves in the same way, show the same pattern of arrangement, whenever the organism is placed under the same circumstances. Yesterday's high tide will never recur, and yesterday's consciousnesses will never recur; but we have a science of psychology, as we have a science of oceanography.
§ 6. The Method of Psychology. — Scientific method may be summed up in the single word ' observation '; the only way to work in science is to observe those phenomena which form the subject-matter of science. And observa- 20 Subject-matter, Method and Problem of Psychology tion implies two things: attention to the phenomena, and record of the phenomena; that is, clear and vivid experi- ence, and an account of the experience in words or formulas.
In order to secure clear experience and accurate report, science has recourse to experiment. An experiment is an observation that can be repeated, isolated and varied. The more frequently you can repeat an observation, the more likely are you to see clearly what is there and to describe accurately what you have seen. The more strictly you can isolate an observation, the easier does your task of observation become, and the less danger is there of your being led astray by irrelevant circumstances, or of placing emphasis on the wrong point. The more widely you can vary an observation, the more clearly will the uniformity of experience stand out, and the better is your chance of discovering laws. All experimental appliances, all labora- tories and instruments, are provided and devised with this one end in view: that the student shall be able to repeat, isolate and vary his observations. — The method of psychology, then, is observation. To distinguish it from the observation of physical science, which is inspection, a looking-at, psychological observation has been termed introspection, a looking-within. But this difference of name must not blind us to the essential like- ness of the methods. Let us take some typical instances.
We may begin with two very simple cases, (i) Suppose that you are shown two paper discs: the one of an uniform violet, the other composed half of red and half of blue. If this second disc is rapidly rotated, the red and blue will mix, as we say, and you will see a certain blue-red, that is, a kind of violet. Your problem is, so to adjust the pro- § 6. The Method of Psychology 21 portions of red and blue in the second disc that the result- ing violet exactly matches the violet of the first disc. You may repeat this set of observations as often as you like; you may isolate the observations by working in a room that is free from other, possibly disturbing colours; you may vary the observations by working to equality of the violets first from a two-colour disc that is distinctly too blue, and secondly from a disc that is distinctly too red. (2) Suppose, again, that the chord c-e-g is struck, and that you are asked to say how many tones it contains. You may repeat this observation; you may isolate it, by working in a quiet room; you may vary it, by having the chord struck at different parts of the scale, in different octaves.
It is clear that, in these instances, there is practically no difference between introspection and inspection. You are using the same method that you would use for counting the swings of a pendulum, or taking readings from a gal- vanometer scale, in the physical laboratory. There is a difference in subject-matter: the colours and the tones are dependent, not independent experiences: but the method is essentially the same.
Now let us take some cases in which the material of in- trospection is more complex. (1) Suppose that a word is called out to you, and that you are asked to observe the effect which this stimulus produces upon consciousness: how the word affects you, what ideas it calls up, and so forth. The observation may be repeated; it may be isolated, — you may be seated in a dark and silent room, free from disturbances; and it may be varied, — different words may be called out, the word may be flashed upon a screen instead of spoken, etc. Here, however, there seems 22 Subject-matter, Method and Problem of Psychology to be a difference between introspection and inspection. The observer who is watching the course of a chemical reaction, or the movements of some microscopical creature, can jot down from moment to moment the different phases of the observed phenomenon. But if you try to report the changes in consciousness, while these changes are in progress, you interfere with consciousness; your transla- tion of the mental experience into words introduces new factors into that experience itself. (2) Suppose, again, that you are observing a feeling or an emotion: a feeling of disappointment or annoyance, an emotion of anger or chagrin. Experimental control is still possible; situations may be arranged, in the psychological laboratory, such that these feelings may be repeated, isolated and varied. But your observation of them interferes, even more seriously than before, with the course of consciousness. Cool consideration of an emotion is fatal to its very exist- ence; your anger disappears, your disappointment evapo- rates, as you examine it.
To overcome this difficulty of the introspective method, students of psychology are usually recommended to delay their observation until the process to be described has run its course, and then to call it back and describe it from memory. Introspection thus becomes retrospection; in- trospective examination becomes /w/ mortem examination. The rule is, no doubt, a good one for the beginner; and there are cases in which even the experienced psychologist will be wise to follow it. But it is by no means universal. For we must remember (a) that the observations in ques- tion may be repeated. There is, then, no reason why the observer to whom the word is called out, or in whom the emotion is set up, should not report at once upon the first § 6. The Method of Psychology 23 stage of his experience: upon the immediate effect of the word, upon the beginnings of the emotive process.1 It is true that this report interrupts the observation. But, after the first stage has been accurately described, further observations may be taken, and the second, third and following stages similarly described; so that presently a complete report upon the whole experience is obtained. There is, in theory, some danger that the stages become artificially separated; consciousness is a flow, a process, and if we divide it up we run the risk of missing certain intermediate links. In practice, how- ever, this danger has proved to be very small; and we may always have recourse to retrospection, and compare our partial results with our memory of the unbroken expe- rience. Moreover, (b) the practised observer gets into an introspective habit, has the introspective attitude ingrained in his system; so that it is possible for him, not only to take mental notes while the observation is in progress, without interfering with consciousness, but even to jot down written notes, as the histologist does while his eye is still held to the ocular of the microscope.