The Principles of Psychology, Volume 1 (of 2)

"By consequence, or train of thoughts, I understand that succession of one thought to another which is called, to distinguish it from discourse in words, mental discourse. When a man thinketh on anything whatsoever, his next thought after is not altogether so casual as it seems to be. Not every thought to every thought succeeds indifferently. But as we have no imagination, whereof we have not formerly had sense, in whole or in parts; so we have no transition from one imagination to another, whereof we never had the like before in our senses. The reason whereof is this. All fancies are motions within us, relics of those made in the sense: and those motions that immediately succeeded one another in the sense continue also together after sense: insomuch as the former coming again to take place, and be predominant, the latter followeth, by coherence of the matter moved, in such manner, as water upon a plane table is drawn which way any one part of it is guided by the finger. But because in sense, to one and the same thing perceived, sometimes one thing, sometimes another succeedeth, it comes to pass in time that, in the imagining of anything, there is no certainty what we shall imagine next; only this is certain, it shall be something that succeeded the same before, at one time or another. This train of thoughts, or mental discourse, is of two sorts. The first is unguided, without design, and inconstant; wherein there is no passionate thought, to govern and direct those that follow, to itself, as the end and scope of some desire, or other passion....

The second is more constant; as being regulated by some desire and design. For the impression made by such things as we desire, or fear, is strong and permanent, or, if it cease for a time, of quick return: so strong is it, sometimes, as to hinder and break our sleep. From desire ariseth the thought of some means we have seen produce the like of that which we aim at; and from the thought of that, the thought of means to that mean; and so continually, till we come to some beginning within our own power. And because the end, by the greatness of the impression, comes often to mind, in case our thoughts begin to wander, they are quickly again reduced into the way: which observed by one of the seven wise men, made him give men this precept, which is now worn out, Respite finem; that is to say, in all your actions, look often upon what you would have, as the thing that directs all your thoughts in the way to attain it.

"The train of regulated thoughts is of two kinds; one, when of an effect imagined we seek the causes, or means that produce it: and this is common to man and beast. The other is, when imagining anything whatsoever, we seek all the possible effects that can by it be produced; that is to say, we imagine what we can do with it, when we have it. Of which I have not at any time seen any sign, but in man only; for this is a curiosity hardly incident to the nature of any living creature that has no other passion but sensual, such as are hunger, thirst, lust, and anger. In sum, the discourse of the mind, when it is governed by design, is nothing but seeking or the faculty of invention, which the Latins called sagacitas, and sollertia; a hunting out of the causes, of some effect, present or past; or of the effects, of some present or past cause."

The most important passage after this of Hobbes is Hume's:

"As all simple ideas may be separated by the imagination, and may be united again in what form it pleases, nothing would be more unaccountable than the operations of that faculty, were it not guided by some universal principles, which render it, in some measure, uniform with itself in all times and places. Were ideas entirely loose and unconnected, chance alone would join them; and 'tis impossible the same simple ideas should fall regularly into complex ones (as they commonly do) without some bond of union among them, some associating quality, by which one idea naturally introduces another. This uniting principle among ideas is not to be considered as an inseparable connection; for that has been already excluded from the imagination. Nor yet are we to conclude that without it the mind cannot join two ideas; for nothing is more free than that faculty: but we are only to regard it as a gentle force, which commonly prevails, and is the cause why, among other things, languages so nearly correspond to each other; nature in a manner pointing to every one those simple ideas which are most proper to be united in a complex one. The qualities from which this association arises, and by which the mind is after this manner conveyed from one idea to another, are three, viz., Resemblance, Contiguity in time or place, and Cause and Effect.

"I believe it will not be very necessary to prove that these qualities produce an association among ideas, and upon the appearance of one idea naturally introduce another. 'Tis plain that in the course of our thinking, and in the constant revolution of our ideas, our imagination runs easily from one idea to any other that resembles it, and that this quality alone is to the fancy a sufficient bond and association. 'Tis likewise evident, that as the senses, in changing their objects, are necessitated to change them regularly, and take them as they lie contiguous to each other, the imagination must by long custom acquire the same method of thinking, and run along the parts of space and time in conceiving its objects. As to the connection that is made by the relation of cause and effect, we shall have occasion afterwards to examine it to the bottom, and therefore shall not at present insist upon it. 'Tis sufficient to observe that there is no relation which produces a stronger connection in the fancy, and makes one idea more readily recall another, than the relation of cause and effect betwixt their objects.... These are therefore the principles of union or cohesion among our simple ideas, and in the imagination supply the place of that inseparable connection by which they are united in our memory. Here is a kind of Attraction, which in the mental world will be found to have as extraordinary effects as in the natural, and to show itself in as many and as various forms.

Its effects are everywhere conspicuous; but as to its causes, they are mostly unknown, and must be resolved into original qualities of human nature, which I pretend not to explain."[494]

"Nothing is requisite to make any man whatever he is, but a sentient principle with this single law.... Not only all our intellectual pleasures and pains but all the phenomena of memory, imagination, volition, reasoning and every other mental affection and operation, are but different modes or cases of the association of ideas."[497]

An eminent French psychologist, M. Ribot, repeats Hume's comparison of the law of association with that of gravitation, and goes on to say:

"It is remarkable that this discovery was made so late. Nothing is simpler, apparently, than to notice that this law of association is the truly fundamental, irreducible phenomenon of our mental life; that it is at the bottom of all our acts; that it permits of no exception; that neither dream, revery, mystic ecstasy, nor the most abstract reasoning can exist without it; that its suppression would be equivalent to that of thought itself. Nevertheless no ancient author understood it, for one cannot seriously maintain that a few scattered lines in Aristotle and the Stoics constitute a theory and clear view of the subject. It is to Hobbes, Hume, and Hartley that we must attribute the origin of these studies on the connection of our ideas. The discovery of the ultimate law of our psychologic acts has this, then, in common with many other discoveries: it came late and seems so simple that it may justly astonish us.

"Perhaps it is not superfluous to ask in what this manner of explanation is superior to the current theory of Faculties.[498] The most extended usage consists, as we know, in dividing intellectual phenomena into classes, in separating those which differ, in grouping together those of the same nature and in giving to these a common name and in attributing them to the same cause; it is thus that we have come to distinguish those diverse aspects of intelligence which are called judgment, reasoning, abstraction, perception, etc. This method is precisely the one followed in Physics, where the words caloric, electricity, gravity, designate the unknown causes of certain groups of phenomena. If one thus never forgets that the diverse faculties are only the unknown causes of known phenomena, that they are simply a convenient means of classifying the facts and speaking of them, if one does not fall into the common fault of making out of them substantial entities, creations which now agree, now disagree, so forming in the intelligence a little republic; then, we can see nothing reprehensible in this distribution into faculties, conformable as it is to the rules of a sound method and of a good natural classification. In what then is Mr. Bain's procedure superior to the method of the faculties? It is that the latter is simply a classification while his is an explanation.

Between the psychology which traces intellectual facts back to certain faculties, and that which reduces them to the single law of association, there is, according to our way of thinking, the same difference that we find in Physics between those who attribute its phenomena to five or six causes, and those who derive gravity caloric, light, etc., from motion. The system of the faculties explains nothing because each one of them is only a flatus vocis which is of value merely through the phenomena which it contains, and signifies nothing more than these phenomena. The new theory, on the contrary, shows that the different processes of intelligence are only diverse cases of a single law; that imagination, deduction, induction, perception, etc., are but so many determinate ways in which ideas may combine with each other; and that the differences of faculties are only differences of association. It explains all intellectual facts, certainly not after the manner of Metaphysics which demands the ultimate and absolute reason of things; but after the manner of Physics which seeks only their secondary and immediate cause."[499]

The inexperienced reader may be glad of a brief indication of the manner in which all the different mental operations may be conceived to consist of images of sensation associated together.

Memory is the association of a present image with others known to belong to the past. Expectation the same, with future substituted for past. Fancy, the association of images without temporal order.

Belief in anything not present to sense is the very lively, strong, and steadfast association of the image of that thing with some present sensation, so that as long as the sensation persists the image cannot be excluded from the mind.

Judgment is 'transferring the idea of truth by association from one proposition to another that resembles it.'[500]

Fear is a transfer of the bodily hurt associated by experience with the thing feared, to the thought of the thing, with the precise features of the hurt left out. Thus we fear a dog without distinctly imagining his bite.

Nothing is easier than for a philosopher of this school to explain from experience such a notion as that of infinitude.

"He sees in it an ordinary manifestation of one of the laws of the association of ideas,—the law that the idea of a thing irresistibly suggests the idea of any other thing which has been often experienced in close conjunction with it, and not otherwise. As we have never had experience of any point of space without other points beyond it, nor of any point of time without others following it, the law of indissoluble association makes it impossible for us to think of any point of space or time, however distant, without having the idea irresistibly realized, in imagination, of other points still more remote. And thus the supposed original and inherent property of these two ideas is completely explained and accounted for by the law of association; and we are enabled to see that if Space or Time were really susceptible of termination, we should be just as unable as we now are to conceive the idea."[501]

"I believe it will be found that we are accustomed to see like things together. When we see a tree, we generally see more trees than one; a sheep, more sheep than one; a man, more men than one. From this observation, I think, we may refer resemblance to the law of frequency [i.e., contiguity], of which it seems to form only a particular case."

"We may have similarity in form with diversity of use, and similarity of use with diversity of form. A rope suggests other ropes and cords, if we look to the appearance; but looking to the use, it may suggest an iron cable, a wooden prop, an iron girding, a leather band, or bevelled gear. In spite of diversity of appearance, the suggestion turns on what answers a common end. If we are very much attracted by sensible appearances, there will be the more difficulty in recalling things that agree only in the use; if, on the other hand, we are profoundly sensitive to the one point of practical efficiency as a tool, the peculiarities not essential to this will be little noticed, and we shall be ever ready to revive past objects corresponding in use to some one present, although diverse in all other circumstances. We become oblivious to the difference between a horse, a steam-engine, and a waterfall, when our minds are engrossed with the one circumstance of moving power. The diversity in these had no doubt for a long time the effect of keeping back their first identification; and to obtuse intellects, this identification might have been for ever impossible. A strong concentration of mind upon the single peculiarity of mechanical force, and a degree of indifference to the general aspect of the things themselves, must conspire with the intellectual energy of resuscitation by similars, in order to summon together in the view three structures so different.

We can see, by an instance like this, how new adaptations of existing machinery might arise in the mind of a mechanical inventor. When it first occurred to a reflecting mind that moving water had a property identical with human or brute force, namely, the property of setting other masses in motion, overcoming inertia and resistance,—when the sight of the stream suggested through this point of likeness the power of the animal,—a new addition was made to the class of prime movers, and when circumstances permitted, this power could become a substitute for the others. It may seem to the modern understanding, familiar with water-wheels and drifting rafts, that the similarity here was an extremely obvious one. But if we put ourselves back into an early state of mind, when running water affected the mind by its brilliancy, its roar, and irregular devastation, we may easily suppose that to identify this with animal muscular energy was by no means an obvious effect. Doubtless when a mind arose, insensible by natural constitution to the superficial aspects of things, and having withal a great stretch of identifying intellect, such a comparison would then be possible. We may pursue the same example one stage further, and come to the discovery of steam power, or the identification of expanding vapor with the previously known sources of mechanical force. To the common eye, for ages, vapor presented itself as clouds in the sky; or as a hissing noise at the spout of a kettle, with the formation of a foggy curling cloud at a few inches' distance.

The forcing up of the lid of a kettle may also have been occasionally observed. But how long was it ere any one was struck with the parallelism of this appearance with a blast of wind, a rush of water, or an exertion of animal muscle? The discordance was too great to be broken through by such a faint and limited amount of likeness. In one mind, however, the identification did take place, and was followed out into its consequences. The likeness had occurred to other minds previously, but not with the same results. Such minds must have been in some way or other distinguished above the millions of mankind; and we are now endeavoring to give the explanation of their superiority. The intellectual character of Watt contained all the elements preparatory to a great stroke of similarity in such a case;—a high susceptibility, both by nature and by education, to the mechanical properties of bodies; ample previous knowledge or familiarity; and indifference to the superficial and sensational effects of things. It is not only possible, however, but exceedingly probable, that many men possessed all these accomplishments; they are of a kind not transcending common abilities. They would in some degree attach to a mechanical education almost as a matter of course. That the discovery was not sooner made supposes that something farther, and not of common occurrence, was necessary; and this additional endowment appears to be the identifying power of Similarity in general; the tendency to detect likeness in the midst of disparity and disguise.

This supposition accounts for the fact, and is consistent with the known intellectual character of the inventor of the steam-engine."[504]

In French, M. Rabier in his chapter on Association,[510] handles the subject more vigorously and acutely than any one. His treatment of it, though short, seems to me for general soundness to rank second only to Hodgson's.