herd for his sheep; a drover for his cattle; and a clerk for his papers, is the consequence of their habit of making nicer discriminations, and of their having more links of association. Each one is a new anchor, as it were, to prevent the mind from being borne away by the intervening currents of scenes and incidents.

These laws of the repeating faculty or modifying circumstances, which determine its relative strength in each particular case, having all degrees of intensity, and acting sometimes together and sometimes in conflict, are capable of being infinitely compounded, and thus give a boundless variety to the mind's repetitions of its previous impressions. The tendency of the mind to repetition, thus modified, is capable of explaining all the phenomena of conception, memory and imagination; and it shows why it is that all conjoined thoughts, whether co-existent or successive, are related either by contiguity of time or place, resemblance or contrast: in other words, that those principles of connexion are not ultimate facts, as has been supposed, but are all referrible to this repeating tendency, as I shall now attempt to show.

First, As to contiguity or proximity of place. If we admit the selfrepeating tendency of the mind, then objects perceived at the same place will be afterwards mutually suggestive. Thus, I have seen an individual-say the late Mr. Duponceau in that chair-the two objects being parts of the same visual impression. A sight of the chair alone, giving a mental impulse similar to that formerly experienced, the mind goes on and completes the picture, that is, the former train, by suggesting the idea of Mr. Duponceau. So if I hear the letters A, B, C, having previously heard them followed by D, E, &c., these last letters rise spontaneously in my mind, by reason of its tendency to repeat its former motions or changes. So if I have heard the words, January, February, the mind, by the same inherent tendency, adds March, &c.

Second, Proximity or contiguity of time. By the process of repetition sight suggests the ideas of sleep, artificial light, suspension of business. In like manner, if any remarkable event has occurred on the 4th of July, the idea of the day may suggest that event, or the idea of the event may suggest the day. So any scene that occurred when the cholera prevailed, for example, or at Christmas, may be renewed or repeated by the mind, on the suggestion of those periods of time when they severally took place. It is to this form of the repeating process that we owe the faculty, or rather the uses of language. For, whenever we have heard the name of an individual, or an object, that is, heard certain sounds conjoined with the sight or conception of such person or object, their presence immediately suggests the name, and the name suggests the person or object. Thus, the sight of the ordinary covering for the head suggests to us the word hat; to a Frenchman it suggests the word chapeau; to a Spaniard, the word sombrero;

This paper was read before the American Philosophical Society.

these different words suggests to these different persons the same object, for such must be the consequence of the mind's repeating its former series of motions or changes. It is in this way that cause and effect mutually suggest each other, they having the same connexion in time as exists between a name and its object, with this difference, that in the latter case the connexion is casual, while that between cause and effect is necessary and invariable.

Third, Resemblance. This principle of association is as familiar to all as the preceding. The sight of a portrait reminds us of the absent original. Nay, one person reminds us of another by a resemblance in a single feature, or gesture, or mode of speech. A piece of red sealingwax may cause us to think of blood, or the wild poppy, &c., and this is equally the result of the self-copying tendency of the mind, when objects resemble each other they put the mind in the same, that is, in a precisely similar state. It is only by our instinctive consciousness of this similarity between our present and past mental states, that we ever perceive resemblance. A former series, containing the resembling object, being thus begun, the mind completes it, and thus is suggested what was formerly associated with that object. In this way, the sight of sealing-wax, producing in my mind the samé (that is, precisely similar) action or change as the sight of blood, may repeat or renew a scene in which I witnessed the shedding of human blood, or mayhap the blood of an ox. So the aquiline nose of John may, by the like process of repetition, remind me of Thomas, with whose image a like aquiline nose was previously conjoined, and made a part of the series which constituted that image.

The difference between the cases of resemblance and proximity is rather apparent than real. In both cases the mind receives a precisely similar impression to one previously received, which gives it the impulse that causes it to repeat its former state. The only difference between them is, that in the case of proximity this similar impression is produced by the same object, seen at different times or places, while in resemblance the similar impression is produced by similar, but different objects.

Similarity has generally been considered as an elementary principle of connexion by psychologists; but Mr. Mill has endeavoured to reduce cases of resemblance to the class of proximity, because like things are often seen together at the same place, or at the same time, as trees in an avenue or wood, sheep in a flock, &c., but as this is not always true, the explanation is unsatisfactory. Thus, the red sealing-wax may remind us of blood, though the two were never before seen together; or a perfect stranger may remind us of a friend or acquaintance; and, putting the mind in the same state, either of the resembling objects may start the train with which the mind has been associated; precisely as in the case with proximity.

Fourth, Contrast. How this principle of association is a consequence

of the self-copying tendency of the mind, is less obvious, but it is equally certain. What do we mean by contrast? Certainly objects of the same class, but differing as much as objects so closely related can differ in a single particular. Thus, high and low; good and bad; vice and virtue; pleasure and pain; north and south; light and darkness; day and night; wet and dry; yes and no-which are the first examples of contrast that chance to present themselves to my mindshow the closest affinity between the contrasted objects or conceptions. They stand in the relation of negative and affirmative; and commonly each one may be expressed by a negation of the other. They have usually been present to the mind at the same time, or rather in immediate succession; for, in the ever recurring wants and occasions of life, if we wish for, or like the one, we fear or dislike the other. In our objection to darkness we desire light. In wanting dry weather, we dread rain, or wanting rain, fear a drought. In feeling cold, we wish for heat. In flying poverty, we wish for wealth. In seeking an affirmative answer, we are fearful of a negative, and so on. These contrasts, that is, opposite affinities, having been always, or at least generally, in the mind together, the one, as in other cases of proximity, naturally suggest the other. Our thoughts habitually oscillating from one contrasted object to the other, as in the case of cause and effect, whenever one of them is presented, the mind, by its self-copying tendency, naturally passes to the other.

But it is alleged that contrast may be a principle of suggestion when the contrasted objects never have been present to the mind together or even present at all. The sight of a giant, for instance, may suggest the idea of a dwarf, though the observer may never before have seen either a giant or a dwarf. Dr. Brown admits the fact, and, on the supposition that contrast is not an original principle of suggestion or association, he offers this explanation of it. Contrasted objects, he says, are striking deviations from the ordinary course of nature, and from this common feature one may suggest the other-thus in fact reducing this relation to that of resemblance. The solution would be plausible, if contrasts were always, like that of the giant and dwarf, deviations from the ordinary course of nature; but it so happens that most contrasts are of the most frequent and familiar recurrence; as day and night, wet and dry, high and low, great and small, &c. How then, it may be asked, can a giant suggest a dwarf to one who had never before seen either? This seeming difficulty is explained by the fact that the link of connexion by which the mind passes from thought to thought is sometimes between the objects themselves, and sometimes it is only between their signs, that is, the words by which they are indicated. Puns, rhymes, alliterations, are all examples of this class of associations. Now, although the spectator may never before have seen either a giant or a dwarf, he was familiar with the contrasted terms of high and low; little and great; and seeing a very tall

and large man, and then according to our general habit of embodying our thoughts, in the habitual signs of those thoughts, that is, on his thinking, in language, that the giant was tall or high, these words would, by reason of the former habitual connexion in his mind between high and low, naturally suggest the word low or little, &c., and thus the mind would pass from the idea of a very tall man, or a giant, to that of a very low or small man, a dwarf.

That our contrasts are often merely verbal, appears from the fact that some words have more than one contrast; and while one of these would be suggested to one man, another would be suggested to another. Thus, right is sometimes contrasted with wrong, and sometimes with left. To a lawyer, the word "right" would be more likely to suggest the word "wrong," than "left;" but to a soldier on drill, the same word would suggest "left" rather than "wrong." Thus, too, man is sometimes contrasted with brute; sometimes with woman; sometimes with boy; and sometimes with horse; and the word would be apt to suggest that particular contrast to each individual with which he had been most familiar. So bread might be contrasted with meat by a commissary; with wine by a minister of the sacrament; and with water by a jailer; for the mind of each would repeat its former train of thought in which bread had formed a part.

It thus appears, that whether our thoughts be connected by proximity of time or of place, by resemblance or contrast, they are always copies of the mind's former trains; and that in consequence of this, its inherent self-copying tendency, the adjoining thoughts of every mental train must come under one of these relations, since they comprehend every class of conjoined ideas or feelings. In the cases of proximity and contrast, the mind being made to begin its process of repetition by a recurrence of the same object as formerly; and in the case of resemblance, by a different object. In other words, the mind being able, by its inherent powers, only to repeat itself, when it passes from idea to idea, the succeeding idea must always be suggested by the preceding one, perceived on some former occasion, which preceding one might have been produced either by the same object, as in the cases of proximity and contrast, or by a different object, but capable, by resemblance, of producing the same state of the mind.

When the succeeding trains of thought follow in the same order of time and place as that in which they were originally perceived, we call the copies acts of the Memory. When the trains are made up of what has been perceived at different times and places, we call them acts of the Imagination. All our conceptions of the future, if they at all vary from the past, are of the latter character. If I think of my dinner yesterday, as it actually was, it is memory; if I think how much better it had been if of canvass-back ducks, it is imagination.

But how is it that the mind, with its tendency to repeat its former acts or movements, does not always copy them in the same order of

time and place? In other words, why does it sometimes imagine rather than remember?

The answer is to be found in those several circumstances or laws which give to the repeating faculty its relative strength for each particular occasion, as recency, frequency of repetition, being accompanied by emotion, &c. The mind obeys whichever of these modifying circumstances has the greatest influence, and that one may suggest something which occurred at another time or place, so as to make a train that had no exact prototype, in which case the train is fancy or imagination. Thus, the sight of that portrait may remind me of Mr. Jefferson; and having recently heard his opinions cited relative to the late war with Mexico, and felt a lively interest in the subject, my mind may be more strongly disposed to think of what would probably have been his views of the war: that is, it may be more strongly drawn to this new train than to copy any former one in which that statesman was an actor. So from the same predominance of feeling, whether of surprise, or sense of injustice, the absence of the statues of Brutus and Cassius, in the funeral procession of Junia, the wife of the one and the sister of the other, caused those individuals to be more strikingly before the minds of the spectators than the twenty other illustrious men whose images were present. Sed præfulgebant Cassius atque Brutus, eo ipso, quod effigies eorum non visebantur. Here imagination prevailed against the senses; that is, the train of thought produced by the associating faculty was more lively than that suggested by actual vision, just as if we were to see a complete alphabet, with the exception of a blank space for a single letter, and our minds should think, as they easily might, more of the omitted letter than of those in sight.

Since every thought may suggest many things to which it had previous relations by proximity or resemblance, the mind is led to one or the other of these remembrances by the influence of the modifying circumstances that have been mentioned. Its process in making the selection is very well explained by Dr. Brown, by the operation of what he calls "the secondary law of suggestion," and which are virtually comprehended in those circumstances that give to the repeating faculty its precise degree of activity and force. These same circumstances which give to the memory this or that direction, do also divert or turn it from memory to imagination.

As the mind cannot pass from idea to idea, that is, carry on a train of thought, except by copying its previous impressions, this same faculty of association furnishes all the materials of our profoundest speculations, and of our simplest acts of reasoning, no less than those of memory and imagination.

Thus, whenever this faculty has suggested a proposition, that is to say, has affirmed or denied somewhat of something, either the predi

* His portrait is in the Hall, with those of other Presidents of the Society.