Among the objects which I have thus observed synchronically, or successively; that is, from which I have had synchronical or successive sensations; there are some which I have so observed frequently; others which I have so observed not frequently: in other words, of my sensations some have been frequently synchronical, others not frequently; some frequently successive, others not frequently. Thus, my sight of roast beef, and my taste of roast beef, have been frequently SYNCHRONICAL; my smell of a rose, and my sight and touch of a rose, have been frequently synchronical; my sight of a stone, and my sensations of its hardness, and weight, have been frequently synchronical. Others of my sensations have not been frequently synchronical: my sight of a lion, and the hearing of his roar; my sight of a knife, and its stabbing a man. My sight of the flash of lightning, and my hearing of the thunder, have been often SUCCESSIVE; the pain of cold, and the pleasure of heat, have been often successive; the sight of a trumpet, and the sound of a trumpet, have been often successive. On the other hand, my sight of hemlock, and my taste of hemlock, have not been often successive: and so on.
It so happens, that, of the objects from which we derive the greatest part of our sensations, most of those which are observed synchronically, are frequently observed synchronically; most of those which are observed successively, are frequently observed successively. In other words, most of our synchronical sensations, have been frequently synchronical; most of our successive sensations, have been frequently successive. Thus, most of our synchronical sensations are derived from the objects around us, the objects which we have the most frequent occasion to hear and see; the members of our family; the furniture of our houses; our food; the instruments of our occupations or amusements. In like manner, of those sensations which we have had in succession, we have had the greatest number repeatedly in succession; the sight of fire, and its warmth; the touch of snow, and its cold; the sight of food, and its taste.
Thus much with regard to the order of SENSATIONS; next with regard to the order of IDEAS.
As ideas are not derived from objects, we should not expect their order to be derived from the order of objects; but as they are derived from sensations, we might by analogy expect, that they would derive their order from that of the sensations; and this to a great extent is the case.
Our ideas spring up, or exist, in the order in which the sensations existed, of which they are the copies.
This is the general law of the “Association of Ideas”; by which term, let it be remembered, nothing is here meant to be expressed, but the order of occurrence.
In this law, the following things are to be carefully observed.
1. Of those sensations which occurred synchronically, the ideas also spring up synchronically. I have seen a violin, and heard the tones of the violin, synchronically. If I think of the tones of the violin, the visible appearance of the violin at the same time occurs to me. I have seen the sun, and the sky in which it is placed, synchronically. If I think of the one, I think of the other at the same time.
One of the cases of synchronical sensation, which deserves the most particular attention, is, that of the several sensations derived from one and the same object; a stone, for example, a flower, a table, a chair, a horse, a man.
From a stone I have had, synchronically, the sensation of colour, the sensation of hardness, the sensations of shape, and size, the sensation of weight. When the idea of one of these sensations occurs, the ideas of all of them occur.26 They exist in my mind synchronically; and their synchronical existence is called the idea of the stone; which, it is thus plain, is not a single idea, but a number of ideas in a particular state of combination.
26 This must be qualified by the fact that the same individual sensation may be found in many groupings, and therefore may not bring up any one aggregate or concrete object in particular. The colour, white, is seen in conjunction with many different shapes, magnitudes, and weight; consequently it does not suggest a specific shape or magnitude. In such a case, the recall may be very various according to circumstances; some individual may have a greater prominence than the rest, and be singled out on that ground; two or three may be brought to view; or a still greater number may be revived.
This is an important limitation of the working of the associating principle. An individual thing is not restored, as a matter of course, unless the link of connexion points to it alone; as is often effected by a plurality of bonds. Thus a musical air is not suggested until as many notes are heard as to distinguish it from every other known air.—B.
Thus, again, I have smelt a rose, and looked at, and handled a rose, synchronically; accordingly the name rose suggests to me all those ideas synchronically; and this combination of those simple ideas is called my idea of the rose.
My idea of an animal is still more complex. The word thrush, for example, not only suggests an idea of a particular colour and shape, and size, but of song, and flight, and nestling, and eggs, and callow young, and others.
My idea of a man is the most complex of all; including not only colour, and shape, and voice, but the whole class of events in which I have observed him either the agent or the patient.
2. As the ideas of the sensations which occurred synchronically, rise synchronically, so the ideas of the sensations which occurred successively, rise successively.
Of this important case of association, or of the successive order of our ideas, many remarkable instances might be adduced. Of these none seems better adapted to the learner than the repetition of any passage, or words; the Lord’s Prayer, for example, committed to memory. In learning the passage, we repeat it; that is, we pronounce the words, in successive order, from the beginning to the end. The order of the sensations is successive. When we proceed to repeat the passage, the ideas of the words also rise in succession, the preceding always suggesting the succeeding, and no other. Our suggests Father, Father suggests which, which suggests art; and so on, to the end. How remarkably this is the case, any one may convince himself, by trying to repeat backwards, even a passage with which he is as familiar as the Lord’s Prayer. The case is the same with numbers. A man can go on with the numbers in the progressive order, one, two, three, &c. scarcely thinking of his act; and though it is possible for him to repeat them backward, because he is accustomed to subtraction of numbers, he cannot do so without an effort.
Of witnesses in courts of justice it has been remarked, that eye-witnesses, and ear-witnesses, always tell their story in the chronological order; in other words, the ideas occur to them in the order in which the sensations occurred; on the other hand, that witnesses, who are inventing, rarely adhere to the chronological order.
3. A far greater number of our sensations are received in the successive, than in the synchronical order. Of our ideas, also, the number is infinitely greater that rise in the successive than the synchronical order.
4. In the successive order of ideas, that which precedes, is sometimes called the suggesting, that which succeeds, the suggested idea; not that any power is supposed to reside in the antecedent over the consequent; suggesting, and suggested, mean only antecedent and consequent, with the additional idea, that such order is not casual, but, to a certain degree, permanent.
5. Of the antecedent and consequent feelings, or the suggesting, and suggested; the antecedent may be either sensations or ideas; the consequent are always ideas. An idea may be excited either by a sensation or an idea. The sight of the dog of my friend is a sensation, and it excites the idea of my friend. The idea of Professor Dugald Stewart delivering a lecture, recals the idea of the delight with which I heard him; that, the idea of the studies in which it engaged me; that, the trains of thought which succeeded; and each epoch of my mental history, the succeeding one, till the present moment; in which I am endeavouring to present to others what appears to me valuable among the innumerable ideas of which this lengthened train has been composed.
6. As there are degrees in sensation, and degrees in ideas; for one sensation is more vivid than another sensation, one idea more vivid than another idea; so there are degrees in association. One association, we say, is stronger than another: First, when it is more permanent than another: Secondly, when it is performed with more certainty: Thirdly, when it is performed with more facility.
It is well known, that some associations are very transient, others very permanent. The case which we formerly mentioned, that of repeating words committed to memory, affords an apt illustration. In some cases, we can perform the repetition, when a few hours, or a few days have elapsed; but not after a longer period. In others, we can perform it after the lapse of many years. There are few children in whose minds some association has not been formed between darkness and ghosts. In some this association is soon dissolved; in some it continues for life.27
27 The difference between transient and permanent recollections turns entirely upon the strength of the association. There is not one specific mode of association suited to temporary recollection and another to permanent; the permanent contains the temporary, as the greater does the less. The reason why a feebler association will suffice for temporary purposes, is that a recent impression still retains something of the hold of a present reality. The chords struck during the actual presence have not ceased to vibrate. It is difficult to estimate with precision the influence of recency; we know it to be very considerable. A thing distinctly remembered for a few hours will be forgotten, or else held as a mere fragment, at the end of a month; while anything that persists for two or three months may be considered as independent of the power of recency, and may last for years.—B.
In some cases the association takes place with less, in some with greater certainty. Thus, in repeating words, I am not sure that I shall not commit mistakes, if they are imperfectly got; and I may at one trial repeat them right, at another wrong: I am sure of always repeating those correctly, which I have got perfectly. Thus, in my native language, the association between the name and the thing is certain; in a language with which I am imperfectly acquainted, not certain. In expressing myself in my own language, the idea of the thing suggests the idea of the name with certainty. In speaking a language with which I am imperfectly acquainted, the idea of the thing does not with certainty suggest the idea of the name; at one time it may, at another not.
That ideas are associated in some cases with more, in some with less facility, is strikingly illustrated by the same instance, of a language with which we are well, and a language with which we are imperfectly, acquainted. In speaking our own language, we are not conscious of any effort; the associations between the words and the ideas appear spontaneous. In endeavouring to speak a language with which we are imperfectly acquainted, we are sensible of a painful effort: the associations between the words and ideas being not ready, or immediate.
7. The causes of strength in association seem all to be resolvable into two; the vividness of the associated feelings; and the frequency of the association.
In general, we convey not a very precise meaning, when we speak of the vividness of sensations and ideas. We may be understood when we say that, generally speaking, the sensation is more vivid than the idea; or the primary, than the secondary feeling; though in dreams, and in delirium, ideas are mistaken for sensations. But when we say that one sensation is more vivid than another, there is much more uncertainty. We can distinguish those sensations which are pleasurable, and those which are painful, from such as are not so; and when we call the pleasurable and painful more vivid, than those which are not so, we speak intelligibly. We can also distinguish degrees of pleasure, and of pain; and when we call the sensation of the higher degree more vivid than the sensation of the lower degree, we may again be considered as expressing a meaning tolerably precise.
In calling one IDEA more vivid than another, if we confine the appellation to the ideas of such SENSATIONS as may with precision be called more or less vivid; the sensations of pleasure and pain, in their various degrees, compared with sensations which we do not call either pleasurable or painful; our language will still have a certain degree of precision. But what is the meaning which I annex to my words, when I say, that my idea of the taste of the pine-apple which I tasted yesterday is vivid; my idea of the taste of the foreign fruit which I never tasted but once in early life, is not vivid? If I mean that I can more certainly distinguish the more recent, than the more distant sensation, there is still some precision in my language; because it seems true of all my senses, that if I compare a distant sensation with a present, I am less sure of its being or not being a repetition of the same, than if I compare a recent sensation with a present one. Thus, if I yesterday had a smell of a very peculiar kind, and compare it with a present smell, I can judge more accurately of the agreement or disagreement of the two sensations, than if I compared the present with one much more remote. The same is the case with colours, with sounds, with feelings of touch, and of resistance. It is therefore sufficiently certain, that the idea of the more recent sensation affords the means of a more accurate comparison, generally, than the idea of the more remote sensation. And thus we have three cases of vividness, of which we can speak with some precision: the case of sensations, as compared with ideas; the case of pleasurable and painful sensations, and their ideas, as compared with those which are not pleasurable or painful; and the case of the more recent, compared with the more remote.28
28 If it be admitted that in the three cases here specified the word vividness, as applied to our impressions, has a definite meaning, it seems to follow that this meaning may be extended in the way of analogy, to other cases than these. There are, for example, sensations which differ from some other sensations like fainter feelings of the same kind, in much the same manner as the idea of a sensation differs from the sensation itself: and we may, by extension, call these sensations less vivid. Again, one idea may differ from another idea in the same sort of way in which the idea of a sensation had long ago differs from that of a similar sensation received recently: that is, it is a more faded copy—its colours and its outlines are more effaced: this idea may fairly be said to be less vivid than the other.
The author himself, a few pages farther on, speaks of some complex ideas as being more “obscure” than others, merely on account of their greater complexity. Obscurity, indeed, in this case, means a different quality from the absence of vividness, but a quality fully as indefinite.
Mr. Bain, whose view of the subject will be found further on, draws a fundamental distinction (already indicated in a former note) between the attributes which belong to a sensation regarded in an intellectual point of view, as a portion of our knowledge, and those which belong to the element of Feeling contained in it; Feeling being here taken in the narrower acceptation of the word, that in which Feeling is opposed to Intellect or Thought. To sensations in their intellectual aspect Mr. Bain considers the term vividness to be inapplicable: they can only be distinct or indistinct. He reserves the word vividness to express the degree of intensity of the sensation, considered in what may be called its emotional aspect, whether of pleasure, of pain, or of mere excitement.
Whether we accept this restriction or not, it is in any case certain, that the property of producing a strong and durable association without the aid of repetition, belongs principally to our pleasures and pains. The more intense the pain or pleasure, the more promptly and powerfully does it associate itself with its accompanying circumstances, even with those which are only accidentally present. In the cases mentioned in the text, a single occurrence of the painful sensation is sufficient to produce an association, which neither time can wear out nor counter-associations dissolve, between the idea of the pain and the ideas of the sensations which casually accompanied it in that one instance, however intrinsically indifferent these may be.—Ed.
That the association of two ideas, but for once, does, in some cases, give them a very strong connection, is within the sphere of every man’s experience. The most remarkable cases are probably those of pain and pleasure. Some persons who have experienced a very painful surgical operation, can never afterwards bear the sight of the operator, however strong the gratitude which they may actually feel towards him. The meaning is, that the sight of the operator, by a strong association, calls up so vividly the idea of the pain of the operation, that it is itself a pain. The spot on which a tender maiden parted with her lover, when he embarked on the voyage from which he never returned, cannot afterwards be seen by her without an agony of grief.
These cases, also, furnish an apt illustration of the superiority which the sensation possesses over the idea, as an associating cause. Though the sight of the surgeon, the sight of the place, would awaken the ideas which we have described, the mere thought of them might be attended with no peculiar effect. Those persons who have the association of frightful objects with darkness, and who are transported with terrors when placed in the dark, can still think of darkness without any emotion.
The same cases furnish an illustration of the effect of recency on the strength of association. The sight, of the affecting spot by the maiden, of the surgeon by the patient, would certainly produce a more intense emotion, after a short, than after a long interval. With most persons, time would weaken, and at last dissolve, the association.
So much with regard to vividness, as a cause of strong associations. Next, we have to consider frequency or repetition; which is the most remarkable and important cause of the strength of our associations.
Of any two sensations, frequently perceived together, the ideas are associated. Thus, at least, in the minds of Englishmen, the idea of a soldier, and the idea of a red coat are associated; the idea of a clergyman, and the idea of a black coat; the idea of a quaker, and of a broad-brimmed hat; the idea of a woman and the idea of petticoats. A peculiar taste suggests the idea of an apple; a peculiar smell the idea of a rose. If I have heard a particular air frequently sung by a particular person, the hearing of the air suggests the idea of the person.
The most remarkable exemplification of the effect of degrees of frequency, in producing degrees of strength in the associations, is to be found in the cases in which the association is purposely and studiously contracted; the cases in which we learn something; the use of words, for example.
Every child learns the language which is spoken by those around him. He also learns it by degrees. He learns first the names of the most familiar objects; and among familiar objects, the names of those which he most frequently has occasion to name; himself, his nurse, his food, his playthings.
A sound heard once in conjunction with another sensation; the word mamma, for example, with the sight of a woman, would produce no greater effect on the child, than the conjunction of any other sensation, which once exists and is gone for ever. But if the word mamma is frequently pronounced, in conjunction with the sight of a particular woman, the sound will by degrees become associated with the sight; and as the pronouncing of the name will call up the idea of the woman, so the sight of the woman will call up the idea of the name.
The process becomes very perceptible to us, when, at years of reflection, we proceed to learn a dead or foreign language. At the first lesson, we are told, or we see in the dictionary, the meaning of perhaps twenty words. But it is not joining the word and its meaning once, that will make the word suggest its meaning to us another time. We repeat the two in conjunction, till we think the meaning so well associated with the word, that whenever the word occurs to us, the meaning will occur along with it. We are often deceived in this anticipation; and finding that the meaning is not suggested by the word, we have to renew the process of repetition, and this, perhaps, again, and again. By force of repetition the meaning is associated, at last, with every word of the language, and so perfectly, that the one never occurs to us without the other.
Learning to play on a musical instrument is another remarkable illustration of the effect of repetition in strengthening associations, in rendering those sequences, which, at first, are slow, and difficult, afterwards, rapid, and easy. At first, the learner, after thinking of each successive note, as it stands in his book, has each time to look out with care for the key or the string which he is to touch, and the finger he is to touch it with, and is every moment committing mistakes. Repetition is well known to be the only means of overcoming these difficulties. As the repetition goes on, the sight of the note, or even the idea of the note, becomes associated with the place of the key or the string; and that of the key or the string with the proper finger. The association for a time is imperfect, but at last becomes so strong, that it is performed with the greatest rapidity, without an effort, and almost without consciousness.
In few cases is the strength of association, derived from repetition, more worthy of attention, than in performing arithmetic. All men, whose practice is not great, find the addition of a long column of numbers, tedious, and the accuracy of the operation, by no means certain. Till a man has had considerable practice, there are few acts of the mind more toilsome. The reason is, that the names of the numbers, which correspond to the different steps, do not readily occur; that is, are not strongly associated with the names which precede them. Thus, 7 added to 5, make 12; but the antecedent, 7 added to 5, is not strongly associated with the consequent 12, in the mind of the learner, and he has to wait and search till the name occurs. Thus, again, 12 and 7 make 19; 19 and 8 make 27, and so on to any amount; but if the practice of the performer has been small, the association in each instance is imperfect, and the process irksome and slow. Practice, however; that is, frequency of repetition; makes the association between each of these antecedents and its proper consequent so perfect, that no sooner is the one conceived than the other is conceived, and an expert arithmetician can tell the amount of a long column of figures, with a rapidity, which seems almost miraculous to the man whose faculty of numeration is of the ordinary standard.
8. Where two or more ideas have been often repeated together, and the association has become very strong, they sometimes spring up in such close combination as not to be distinguishable. Some cases of sensation are analogous. For example; when a wheel, on the seven parts of which the seven prismatic colours are respectively painted, is made to revolve rapidly, it appears not of seven colours, but of one uniform colour, white. By the rapidity of the succession, the several sensations cease to be distinguishable; they run, as it were, together, and a new sensation, compounded of all the seven, but apparently a simple one, is the result. Ideas, also, which have been so often conjoined, that whenever one exists in the mind, the others immediately exist along with it, seem to run into one another, to coalesce, as it were, and out of many to form one idea; which idea, however in reality complex, appears to be no less simple, than any one of those of which it is compounded.
The word gold, for example, or the word iron, appears to express as simple an idea, as the word colour, or the word sound. Yet it is immediately seen, that the idea of each of those metals is made up of the separate ideas of several sensations; colour, hardness, extension, weight. Those ideas, however, present themselves in such intimate union, that they are constantly spoken of as one, not many. We say, our idea of iron, our idea of gold; and it is only with an effort that reflecting men perform the decomposition.
The idea expressed by the term weight, appears so perfectly simple, that he is a good metaphysician, who can trace its composition. Yet it involves, of course, the idea of resistance, which we have shewn above to be compounded, and to involve the feeling attendant upon the contraction of muscles; and the feeling or feelings, denominated Will; it involves the idea, not of resistance simply, but of resistance in a particular direction; the idea of direction, therefore, is included in it, and in that are involved the ideas of extension, and of place and motion, some of the most complicated phenomena of the human mind.
The ideas of hardness and extension have been so uniformly regarded as simple, that the greatest metaphysicians have set them down as the copies of simple sensations of touch. Hartley and Darwin, were, I believe, the first who thought of assigning to them a different origin.
We call a thing hard, because it resists compression, or separation of parts; that is, because to compress it, or separate it into parts, what we call muscular force is required. The idea, then, of muscular action, and of all the feelings which go to it, are involved in the idea of hardness.
The idea of extension is derived from the muscular feelings in what we call the motion of parts of our own bodies; as for example, the hands. I move my hand along a line; I have certain sensations; on account of these sensations, I call the line long, or extended. The idea of lines in the direction of length, breadth, and thickness, constitutes the general idea of extension. In the idea of extension, there are included three of the most complex of our ideas; motion; time, which is included in motion; and space, which is included in direction. We are not yet prepared to explain the simple ideas which compose the very complex ideas, of motion, space, and time; it is enough at present to have shewn, that in the idea of extension, which appears so very simple, a great number of ideas are nevertheless included; and that this is a case of that combination of ideas in the higher degrees of association, in which the simple ideas are so intimately blended, as to have the appearance, not of a complex, but of a simple idea.
It is to this great law of association, that we trace the formation of our ideas of what we call external objects; that is, the ideas of a certain number of sensations, received together so frequently that they coalesce as it were, and are spoken of under the idea of unity. Hence, what we call the idea of a tree, the idea of a stone, the idea of a horse, the idea of a man.
In using the names, tree, horse, man, the names of what I call objects, I am referring, and can be referring, only to my own sensations; in fact, therefore, only naming a certain number of sensations, regarded as in a particular state of combination; that is, concomitance. Particular sensations of sight, of touch, of the muscles, are the sensations, to the ideas of which, colour, extension, roughness, hardness, smoothness, taste, smell, so coalescing as to appear one idea, I give the name, idea of a tree.
To this case of high association, this blending together of many ideas, in so close a combination that they appear not many ideas, but one idea, we owe, as I shall afterwards more fully explain, the power of classification, and all the advantages of language. It is obviously, therefore, of the greatest moment, that this important phenomenon should be well understood.
9. Some ideas are by frequency and strength of association so closely combined, that they cannot be separated. If one exists, the other exists along with it, in spite of whatever effort we make to disjoin them.
For example; it is not in our power to think of colour, without thinking of extension; or of solidity, without figure. We have seen colour constantly in combination with extension, spread, as it were, upon a surface. We have never seen it except in this connection. Colour and extension have been invariably conjoined. The idea of colour, therefore, uniformly comes into the mind, bringing that of extension along with it; and so close is the association, that it is not in our power to dissolve it. We cannot, if we will, think of colour, but in combination with extension. The one idea calls up the other, and retains it, so long as the other is retained.
This great law of our nature is illustrated in a manner equally striking, by the connection between the ideas of solidity and figure. We never have the sensations from which the idea of solidity is derived, but in conjunction with the sensations whence the idea of figure is derived. If we handle any thing solid, it is always either round, square, or of some other form. The ideas correspond with the sensations. If the idea of solidity rises, that of figure rises along with it. The idea of figure which rises, is, of course, more obscure than that of extension; because, figures being innumerable, the general idea is exceedingly complex, and hence, of necessity, obscure. But, such as it is, the idea of figure is always present when that of solidity is present; nor can we, by any effort, think of the one without thinking of the other at the same time.
Of all the cases of this important law of association, there is none more extraordinary than what some philosophers have called, the acquired perceptions of sight.
When I lift my eyes from the paper on which I am writing, I see the chairs, and tables, and walls of my room, each of its proper shape, and at its proper distance. I see, from my window, trees, and meadows, and horses, and oxen, and distant hills. I see each of its proper size, of its proper form, and at its proper distance; and these particulars appear as immediate informations of the eye, as the colours which I see by means of it.
Yet, philosophy has ascertained, that we derive nothing from the eye whatever, but sensations of colour; that the idea of extension, in which size, and form, and distance are included, is derived from sensations, not in the eye, but in the muscular part of our frame. How, then, is it, that we receive accurate information, by the eye, of size, and shape, and distance? By association merely.29
29 We derive through the eye (1) sensations of light in its various degrees, and of colours and their shades; (2) visible form and visible magnitude, together with their changes; and also visible movements. The second group of feelings depends on the movements of the eyes; and they are feelings of activity, or of muscular expenditure. We have, besides, a certain internal muscular sensibility to the alterations of the eye ball in adjusting for distance—B.
The colours upon a body are different, according to its figure, its distance, and its size. But the sensations of colour, and what we may here, for brevity, call the sensations of extension, of figure, of distance, have been so often united, felt in conjunction, that the sensation of the colour is never experienced without raising the ideas of the extension, the figure, the distance, in such intimate union with it, that they not only cannot be separated, but are actually supposed to be seen. The sight, as it is called, of figure, or distance, appearing, as it does, a simple sensation, is in reality a complex state of consciousness; a sequence, in which the antecedent, a sensation of colour, and the consequent, a number of ideas, are so closely combined by association, that they appear not one idea, but one sensation.
Some persons, by the folly of those about them, in early life, have formed associations between the sound of thunder, and danger to their lives. They are accordingly in a state of agitation during a thunder storm. The sound of the thunder calls up the idea of danger, and no effort they can make, no reasoning they can use with themselves, to show how small the chance that they will be harmed, empowers them to dissolve the spell, to break the association, and deliver themselves from the tormenting idea, while the sensation or the expectation of it remains.
Another very familiar illustration may be adduced. Some persons have what is called an antipathy to a spider, a toad, or a rat. These feelings generally originate in some early fright. The idea of danger has been on some occasion so intensely excited along with the touch or sight of the animal, and hence the association so strongly formed, that it cannot be dissolved. The sensation, in spite of them, excites the idea, and produces the uneasiness which the idea imports.
The following of one idea after another idea, or after a sensation, so certainly that we cannot prevent the combination, nor avoid having the consequent feeling as often as we have the antecedent, is a law of association, the operation of which we shall afterwards find to be extensive, and bearing a principal part in some of the most important phenomena of the human mind.
As there are some ideas so intimately blended by association, that it is not in our power to separate them; there seem to be others, which it is not in our power to combine. Dr. Brown, in exposing some errors of his predecessors, with respect to the acquired perceptions of sight, observes: “I cannot blend my notions of the two surfaces, a plane, and a convex, as one surface, both plane and convex, more than I can think of a whole which is less than a fraction of itself, or a square of which the sides are not equal.” The case, here, appears to be, that a strong association excludes whatever is opposite to it. I cannot associate the two ideas of assafœtida, and the taste of sugar. Why? Because the idea of assafœtida is so strongly associated with the idea of another taste, that the idea of that other taste rises in combination with the idea of assafœtida, and of course the idea of sugar does not rise. I have one idea associated with the word pain. Why can I not associate pleasure with the word pain? Because another indissoluble association springs up, and excludes it. This is, therefore, only a case of indissoluble association; but one of much importance, as we shall find when we come to the exposition of some of the more complicated of our mental phenomena.30
30 Some further elucidation seems needful of what is here said, in so summary a manner, respecting ideas which it is not in our power to combine: an inability which it is essential to the analysis of some of the more complex phenomena of mind that we should understand the meaning of. The explanation is indicated, but hardly more than indicated, in the text.
It seems to follow from the universal law of association, that any idea could be associated with any other idea, if the corresponding sensations, or even the ideas themselves, were presented in juxtaposition with sufficient frequency. If, therefore, there are ideas which cannot be associated with each other, it must be because there is something that prevents this juxtaposition. Two conditions hence appear to be required, to render ideas incapable of combination. First, the sensations must be incapable of being had together. If we cannot associate the taste of assafœtida with the taste of sugar, it is implied, that we cannot have the taste of assafœtida along with the taste of sugar. If we could, a sufficient experience would enable us to associate the ideas. Here, therefore, is one necessary condition of the impossibility of associating certain ideas with one another. But this condition, though necessary, is not sufficient. We are but too capable of associating ideas together though the corresponding external facts are really incompatible. In the case of many errors, prejudices, and superstitions, two ideas are so closely and obstinately associated, that the man cannot, at least for the time, help believing that the association represents a real coexistence or sequence between outward facts, though such coexistence or sequence may contradict a positive law of the physical world. There is therefore a further condition required to render two ideas unassociable, and this is, that one of them shall be already associated with some idea which excludes the other. Thus far the analysis is carried in the author’s text. But the question remains, what ideas exclude one another? On careful consideration I can only find one case of such exclusion: when one of the ideas either contains, or raises up by association, the idea of the absence of the other. I am aware of no case of absolute incompatibility of thought or of imagination, except between the presence of something and its absence; between an affirmative and the corresponding negative. If an idea irresistibly raises up the idea of the absence of a certain sensation, it cannot become associated with the idea of that sensation; for it is impossible to combine together in the same mental representation, the presence of a sensation and its absence.
We are not yet, however, at the end of the difficulty; for it may be objected, that the idea of the absence of anything is the idea of a negation, of a nullity; and the idea of nothing must itself be nothing—no idea at all. This objection has imposed upon more than one metaphysician; but the solution of the paradox is very simple. The idea of the presence of a sensation is the idea of the sensation itself along with certain accompanying circumstances: the idea of the absence of the sensation is the idea of the same accompanying circumstances without the sensation. For example: my idea of a body is the idea of a feeling of resistance, accompanying a certain muscular action of my own, say of my hand; my idea of no body, in other words, of empty space, is the idea of the same or a similar muscular action of my own, not attended by any feeling of resistance. Neither of these is an idea of a mere negation; both are positive mental representations: but inasmuch as one of them includes the negation of something positive which is an actual part of the other, they are mutually incompatible: and any idea which is so associated with one of them as to recall it instantly and irresistibly, is incapable of being associated with the other.
The instance cited by the author from Dr. Brown, is a good illustration of the law. We can associate the ideas of a plane and of a convex surface as two surfaces side by side; but we cannot fuse the two mental images into one, and represent to ourselves the very same series of points giving us the sensations we receive from a plane surface and those we receive from a convex surface both at once. That this cannot but be so, is a corollary from the elementary law of association. Not only has no instance ever occurred in our experience of a surface which gave us at the same moment both these sets of sensations; but whenever in our experience a surface originally plane, came to give us the sensations we receive from a convex surface (as for instance when we bend a flat sheet of paper), it, at the very same moment, ceased to be, or to appear, a plane. The commencement of the one set of sensations has always been simultaneous with the cessation of the other set, and this experience, not being affected by any change of circumstances, has the constancy and invariability of a law of nature. It forms a correspondingly strong association; and we become unable to have an idea of either set of sensations, those of planeness or those of convexity, without having the idea of the disappearance of the other set, if they existed previously. I believe it will be found that all the mental incompatibilities, the impossibilities of thought, of which so much is made by a certain class of metaphysicians, can be accounted for in a similar manner.—Ed.
10. It not unfrequently happens in our associated feelings, that the antecedent is of no importance farther than as it introduces the consequent. In these cases, the consequent absorbs all the attention, and the antecedent is instantly forgotten. Of this a very intelligible illustration is afforded by what happens in ordinary discourse. A friend arrives from a distant country, and brings me the first intelligence of the last illness, the last words, the last acts, and death of my son. The sound of the voice, the articulation of every word, makes its sensation in my ear; but it is to the ideas that my attention flies. It is my son that is before me, suffering, acting, speaking, dying. The words which have introduced the ideas, and kindled the affections, have been as little heeded, as the respiration which has been accelerated, while the ideas were received.
It is important in respect to this case of association to remark, that there are large classes of our sensations, such as many of those in the alimentary duct, and many in the nervous and vascular systems, which serve, as antecedents, to introduce ideas, as consequents; but as the consequents are far more interesting than themselves, and immediately absorb the attention, the antecedents are habitually overlooked; and though they exercise, by the trains which they introduce, a great influence on our happiness or misery, they themselves are generally wholly unknown.
That there are connections between our ideas and certain states of the internal organs, is proved by many familiar instances. Thus, anxiety, in most people, disorders the digestion. It is no wonder, then, that the internal feelings which accompany indigestion, should excite the ideas which prevail in a state of anxiety. Fear, in most people, accelerates, in a remarkable manner, the vermicular motion of the intestines. There is an association, therefore, between certain states of the intestines, and terrible ideas; and this is sufficiently confirmed by the horrible dreams to which men are subject from indigestion; and the hypochondria, more or less afflicting, which almost always accompanies certain morbid states of the digestive organs. The grateful food which excites pleasurable sensations in the mouth, continues them in the stomach; and, as pleasures excite ideas of their causes, and these of similar causes, and causes excite ideas of their effects, and so on, trains of pleasurable ideas take their origin from pleasurable sensations in the stomach. Uneasy sensations in the stomach, produce analogous effects. Disagreeable sensations are associated with disagreeable circumstances: a train is introduced, in which, one painful idea following another, combinations, to the last degree afflictive, are sometimes introduced, and the sufferer is altogether overwhelmed by dismal associations.31 32
31 There is more than association in the case here supposed. Fear, anxiety, and painful emotions generally, cause disorder in the digestive and other vital functions, as a part of their nature. Every mental state can be proved to have its counterpart physical state; joy, sorrow, fear, are each embodied in a distinct group of physical effects in the nervous system, the muscular movements, and the organic processes. The physical side of agreeable emotions, as a rule, is a heightened tone of the purely animal functions. The physical side of fear is a complicated series of effects, one of them being the depression of the organic processes, digestion among the rest. In this respect, however, it more or less resembles severe pain, sorrow, shame, remorse, and other states, characterised by the general phrase “depressing passions;” the depression being both mental and physical.
The reciprocal agency described in the text, whereby the painful sensations of indigestion induce fear, is not dependent on the association of ideas, but on the deep connections of the emotional states with one another, through their physical accompaniments. A painful feeling of indigestion has much in common with states of depression due to mental causes, as, for example, the shock of a misfortune, fear, sorrow, and the like. From this alliance it favours the ideas of depressing states. It does more; it directly reduces that vigorous tone of the system, which is the support of the courageous and sanguine disposition; and hence, surrenders the mind an easy prey to any chance incentive of alarm or anxiety.—B.
32 The law of association laid down in this section ranks among the principal of what may be termed the laws of Obliviscence. It is one of the widest in its action, and most important in its consequences of all the laws of the mind; and the merit of the author, in the large use he makes of it is very great, as, though it is the key that unlocks many of the more mysterious phenomena of the mind, it is among the least familiar of the mental laws, and is not only overlooked by the great majority of psychologists, but some, otherwise of merit, seem unable to see and understand the law after any quantity of explanation.
The first, however, of the examples by which the author illustrates this law, is not marked by his usual felicity. Its shortcomings are pointed out by Mr. Bain in the preceding note. The internal feelings (says the author) which accompany indigestion, introduce trains of ideas (as in the case of horrible dreams, and of hypochondria) which are acutely painful, and may embitter the whole existence, while the sensations themselves, being comparatively of little interest, are unheeded and forgotten. It is true that the sensations in the alimentary canal, directly produced by indigestion, though (as every one knows) in some cases intense, are in others so slight as not to fix the attention, and yet may be followed by melancholy trains of thought, the connection of which with the state of the digestion may be entirely unobserved: but by far the most probable supposition appears to be, that these painful trains are not excited by the sensations, but that they and the sensations are joint or successive effects of a common organic cause. It is difficult to comprehend how these obscure sensations can excite the distressing trains of ideas by the laws of association; for what opportunity have these sensations usually had of becoming associated, either synchronously or successively, with those ideas? The explanation, in the text, of this difficulty, seems surprisingly insufficient. Anxiety, in most people, disorders the digestion; and consequently, according to the author, the sensations of indigestion excite the ideas which prevail in a state of anxiety. If that were the true explanation, the only persons with whom indigestion would depress the spirits, would be those who had suffered previous depression of spirits, sufficient in duration and intensity to disorder the digestion, and to keep it disordered long enough to effect a close and inseparable cohesion between even very slight sensations of indigestion and painful ideas excited by other causes. Surely this is not the fact. The theory has a true application in the case of the confirmed hypochondriac. When the sensations have been repeatedly experienced along with the melancholy trains of thought, a direct association is likely to grow up between the two; and when this has been effected, the first touch of the sensations may bring back in full measure the miserable mental state which had coexisted with them, thus increasing not only the frequency of its recurrence, but, by the conjunction of two exciting causes, the intensity of the misery. But the origin of the state must be looked for elsewhere, and is probably to be sought in physiology.
The other example in the text seems still less relevant. Fear tends to accelerate the peristaltic motion, therefore there is a connection between certain states of the intestines and terrible ideas. To make this available for the author’s purpose, the consequence of the connection ought to be, that acceleration of the peristaltic motion excites ideas of terror. But does it? The state of indigestion characteristic of hypochondria is not looseness of the bowels, but is commonly attended with the exact opposite. The author’s usual acuteness of discernment seems to have been, in these cases, blunted by an unwillingness to admit the possibility that ideas as well as sensations may be directly affected by material conditions. But if, as he admits, ideas have a direct action on our bodily organs, a prima facie case is made out for the localization of our ideas, equally with our sensations, in some part of our bodily system; and there is at least no antecedent presumption against the supposition that the action may be reciprocal—that as ideas sometimes derange the organic functions, so derangements of organic functions may sometimes modify the trains of our ideas by their own physical action on the brain and nerves, and not through the associations connected with the sensations they excite.—Ed.
In illustration of the fact, that sensations and ideas, which are essential to some of the most important operations of our minds, serve only as antecedents to more important consequents, and are themselves so habitually overlooked, that their existence is unknown, we may recur to the remarkable case which we have just explained, of the ideas introduced by the sensations of sight. The minute gradations of colour, which accompany varieties of extension, figure, and distance, are insignificant. The figure, the size, the distance, themselves, on the other hand, are matters of the greatest importance. The first having introduced the last, their work is done. The consequents remain the sole objects of attention, the antecedents are forgotten; in the present instance, not completely; in other instances, so completely, that they cannot be recognised.33 34
33 Perhaps the most remarkable case of sensations overlooked on their own account, and considered only as a means of suggesting something else, is the visual, or retinal, magnitude of objects seen by the eye. This is probably the most delicate sensibility within the compass of the mind; and yet we habitually disregard it for all things near us, and use it solely for perceiving real magnitude as estimated by our locomotive and other members. The visual magnitude of a table, or other article in a room, is never thought of for itself; although incessantly fluctuating we never think of the fluctuations; we pass from these to the one constant perception, named the true or real magnitude. It is only for remote objects, as the sun and moon, the clouds, the distant hills, that the retinal magnitude abides with us in its own proper character. In looking down a vista, we may also be aroused to the feeling of retinal magnitude. For perspective drawing, it is necessary that we should arrest the strong tendency to pass from the visible, to the real, forms and dimensions of things.—B.
34 The reader, it may be hoped, is now familiar with the important psychological fact, so powerfully grasped and so discerningly employed by Hartley and the author of the Analysis,—that when, through the frequent repetition of a series of sensations, the corresponding train of ideas rushes through the mind with extreme rapidity, some of the links are apt to disappear from consciousness as completely as if they had never formed part of the series. It has been a subject of dispute among philosophers which of three things takes place in this case. Do the lost ideas pass through the mind without consciousness? Do they pass consciously through the mind and are they then instantly forgotten? Or do they never come into the mind at all, being, as it were, overleaped and pressed out by the rush of the subsequent ideas?
It would seem, at first sight, that the first and third suppositions involve impossibilities, and that the second, therefore, is the only one which we are at liberty to adopt. As regards the first, it may be said—How can we have a feeling without feeling it, in other words, without being conscious of it? With regard to the third, how, it may be asked, can any link of the chain have been altogether absent, through the pressure of the subsequent links? The subsequent ideas are only there because called up by it, and would not have arisen at all unless it had arisen first, however short a time it may have lasted. These arguments seem strong, but are not so strong as they seem.
In favour of the first supposition, that feelings may be unconsciously present, various facts and arguments are adduced by Sir William Hamilton in his Lectures; but I think I have shewn in another work, that the arguments are inconclusive, and the facts equally reconcilable with the second of the three hypotheses. That a feeling should not be felt appears to me a contradiction both in words and in nature. But, though a feeling cannot exist without being felt, the organic state which is the antecedent of it may exist, and the feeling itself not follow. This happens, either if the organic state is not of sufficient duration, or if an organic state stronger than itself, and conflicting with it, is affecting us at the same moment. I hope to be excused for quoting what I have said elsewhere on this subject (Examination of Sir William Hamilton’s Philosophy, ch. 15).
“In the case, for instance, of a soldier who receives a wound in battle, but in the excitement of the moment is not aware of the fact, it is difficult not to believe that if the wound had been accompanied by the usual sensation, so vivid a feeling would have forced itself to be attended to and remembered. The supposition which seems most probable is, that the nerves of the particular part were affected as they would have been by the same cause in any other circumstances, but that, the nervous centres being intensely occupied with other impressions, the affection of the local nerves did not reach them, and no sensation was excited. In like manner, if we admit (what physiology is rendering more and more probable) that our mental feelings, as well as our sensations, have for their physical antecedents particular states of the nerves; it may well be believed that the apparently suppressed links in a chain of association, those which Sir William Hamilton considers as latent, really are so; that they are not, even momentarily, felt; the chain of causation being continued only physically, by one organic state of the nerves succeeding another so rapidly that the state of mental consciousness appropriate to each is not produced. We have only to suppose, either that a nervous modification of too short duration does not produce any sensation or mental feeling at all, or that the rapid succession of different nervous modifications makes the feelings produced by them interfere with each other, and become confounded in one mass. The former of these suppositions is extremely probable, while of the truth of the latter we have positive proof. An example of it is the experiment which Sir W. Hamilton quoted from Mr. Mill, and which had been noticed before either of them by Hartley. It is known that the seven prismatic colours, combined in certain proportions, produce the white light of the solar ray. Now, if the seven colours are painted on spaces bearing the same proportion to one another as in the solar spectrum, and the coloured surface so produced is passed rapidly before the eyes, as by the turning of a wheel, the whole is seen as white. The physiological explanation of this phenomenon may be deduced from another common experiment. If a lighted torch, or a bar heated to luminousness, is waved rapidly before the eye, the appearance produced is that of a ribbon of light; which is universally understood to prove that the visual sensation persists for a certain short time after its cause has ceased. Now, if this happens with a single colour, it will happen with a series of colours: and if the wheel on which the prismatic colours have been painted, is turned with the same rapidity with which the torch was waved, each of the seven sensations of colour will last long enough to be contemporaneous with all the others, and they will naturally produce by their combination the same colour as if they had, from the beginning, been excited simultaneously. If anything similar to this obtains in our consciousness generally (and that it obtains in many cases of consciousness there can be no doubt) it will follow that whenever the organic modifications of our nervous fibres succeed one another at an interval shorter than the duration of the sensations or other feelings corresponding to them, those sensations or feelings will, so to speak, overlap one another, and becoming simultaneous instead of successive, will blend into a state of feeling, probably as unlike the elements out of which it is engendered, as the colour white is unlike the prismatic colours. And this may be the source of many of those states of internal or mental feeling which we cannot distinctly refer to a prototype in experience, our experience only supplying the elements from which, by this kind of mental chemistry, they are composed. The elementary feelings may then be said to be latently present, or to be present but not in consciousness. The truth, however, is that the feelings themselves are not present, consciously or latently, but that the nervous modifications which are their usual antecedents have been present, while the consequents have been frustrated, and another consequent has been produced instead.”
In this modified form, therefore, the first of the three hypotheses may possibly be true. Let us now consider the third, that of the entire elision of some of the ideas which form the associated train. This supposition seemed to be inadmissible, because the loss of any link would, it was supposed, cause the chain itself to break off at that point. To make the hypothesis possible, it is only, however, necessary to suppose, that, while the association is acquiring the promptitude and rapidity which it ultimately attains, each of the successive ideas abides for a brief interval in our consciousness after it has already called up the idea which is to succeed it. Each idea in the series, though introduced, not by synchronous, but by successive association, is thus, during a part of its continuance, synchronous with the idea which introduced it: and as the rapidity of the suggestions increases by still further repetition, an idea may become synchronous with another which was originally not even contiguous to it, but separated from it by an intervening link; or may come into immediate instead of mediate sequence with such an idea. When either of these states of things has continued for some time, a direct association of the synchronous or of the successive kind will be generated between two ideas which are not proximate links in the chain; A will acquire a direct power of exciting C, independently of the intervening idea B. If, then, B is much less interesting than C, and especially if B is of no importance at all in itself, but only by exciting C, and has therefore nothing to make the mind dwell on it after C has been reached, the association of A with C is likely to become stronger than that of A with B: C will be habitually excited directly by A; as the mind runs off to the further ideas suggested by C, B will cease to be excited at all; and the train of association, like a stream which breaking though its bank cuts off a bend in its course, will thenceforth flow in the direct line AC, omitting B. This supposition accounts more plausibly than either of the others for the truly wonderful rapidity of thought, since it does not make so large a demand as the other theories on our ability to believe that a prodigious number of different ideas can successively rush through the mind in an instant too short for measurement.
The result is, that all the three theories of this mental process seem to be quite possible; and it is not unlikely that each of them may be the real process in some cases, either in different persons, or in the same persons under different circumstances. I can only remit the question to future psychologists, who may be able to contrive crucial experiments for deciding among these various possibilities.—Ed.