CHAPTER TENTH.

CASUAL ASSOCIATIONS.

§. 205. Association sometimes misleads our judgments.

It is necessary in this part of the history of the mind, to refer again particularly to the great law of Association. There are some cases, where the power of association so misleads us,that we cannot easily form a correct judgment of the true nature of things. Every object of thought, in order to be fully understood, ought to be so much in our power, that we may examine it separately from all other objects. Whenever, therefore, it happens from any circumstances, that the power of association so combines one object of thought with another, that the object cannot readily be looked at and examined by itself, it so far has the effect to perplex and hinder correct judg

ment.

It will be found, when we look into our minds, that there exist a few associations or combinations of thought of this kind, which are obstinate and almost invincible. To explain the origin, and to correct the erroneous tendencies of all such connections of thought, although the number of such as we have now in view cannot be large, would occupy us too long. The examination of a few somewhat striking instances will not only throw light on the philosophy of the mind in general, but will be of some practical benefit. -Other instances of CASUAL ASSOCIA

TION, which have a less degree of strength, and exert a less considerable influence in disturbing the just exercise. of the intellect, will require some examination hereafter. The whole subject of Prejudices, which has a conspicuous place in every practical system of Mental Philosophy, is necessarily taken up in a great degree with such cases. §. 206. Casual association in respect to the place of sen

sensation.

One of the casual associations of that extreme kind, which we have now especial reference to, concerns the place, or rather the supposed place of sensation.-All sensation, it will not be forgotten, is in the mind. Whatever is inanimate or material can of course have no feeling. Nevertheless if a wound be inflicted on the hand or foot, we seem to experience the sensation of pain in that particular place. When we merely bring the hand in contact with a warm or cold body, we even then assign a local habitation to the subsequent feeling, and it clearly seems to be, not in the mind, but in the hand.

This reference of the sensation to the outward organ and place, instead of thinking of it as existing in the soul, is the result of an early and strong association. As the wound in the hand for instance is the cause of the painful feeling, the consequence is, that the sensation, and the place whence it arose constantly go together in our thoughts. The result of this connection, which has been repeated and continued from our youth up, is that we find it extremely difficult in later life to separate them, even with the greatest effort. So difficult is it, that a soldier, whose arm or leg has been amputated, still speaks of feeling pain in those limbs, though they are now perhaps buried in the earth or the depths of the sea.

Although we are liable in these cases to be led into a mistake, if we do not guard against it with care, it is perhaps an obvious remark, that the foundation of this liability to errour is laid in our constitution for beneficent ends. It is not ordinarily so important in a practical point of view, that we should attend to the internal feeling, as

to the external part which is affected. An injury in the external senses, the muscles, or the limbs, if it be not attended to, soon affects other parts of the body and even life itself. Hence Providence has put us in the way to form this strong and almost unconquerable mental habit, in order to secure protection, where it seems to be most urgently and frequently needed.

§. 207. Connection of our ideas of extension and time.

If we examine carefully our notions of Time, we shall find here also a CASUAL ASSOCIATION of long continuance and of great strength. It is believed to be the fact, that Time, as it exists in the apprehensions of most persons, is regarded as something extended. It is not necessary to delay here,to undertake a definition of time, to show what it is in the abstract, or to give a history of the notion which we form of it. Taking it for granted, that every one knows what is meant when we use that term, we merely assert here, that for some cause or other it is exceedingly difficult to think of it, except in the light of a modification of EXTENSION. The correctness of this remark may not perhaps appear perfectly obvious at first ; but the expressions, which we apply to intervals of duration, are an evidence of its truth.

We say before such a time or after such a time, the same as before or after any material object; we speak of a long or a short time with no more hesitation than of a long or short distance, of a long or short bridge, or railway, or any other object of extension. We utter ourselves precisely in the same way we should do, if we were certain of having detected some real analogy between the two, between length and shortness in material substances, and what are called length and shortness in time. But it is not too much to say, that there is no such analogy, no such similitude; nor is it worth while to anticipate, that we shall ever be able to detect such analogy or similitude, until we can in practice apply the measures of feet, ells, roods, &c. to hours, and days, and weeks. How then can it be accounted for, that we apply terms, nearly in the

same way, as if this were the case, and as if such measurements could be made?

The strong association of these ideas has most probably arisen in this manner, viz. from our constantly measuring one of these quantities by the other. It is the common method to measure time by motion, and motion is measured by extension. In an hour the hand of a clock moves over a certain space; in two hours over double the space, and so on.--No doubt it is convenient to apply the terms "long" and "short," "before" and "after," and others similar, to time. We could not well dispense with them. But it ought to be remembered, if we would have right notions of things, that the application of those expressions has arisen from the mode in which we measure time, and that time and extension are essentially distinct in their nature.

§. 209. Of high and low notes in music.

We speak of high and low in reference to notes. in music, the same as of the high or low position of material bodies. There is supposed to be some analogy between the relation, which the notes in the scale of music bear to each other, and the relation of superiority and inferiority in the position of bodies of matter. But it is impossible to prove the existence of such analogy, however generally it may have been supposed; and the supposition itself of its existence has no doubt arisen from a casual association of ideas, which has acquired strength by lapse of time and by repetition.

A proof of this association of ideas being purely accidental is that an association, the very reverse of this, was once prevalent. It is remarked in the preface to Gregory's edition to Euclid's works, that the more ancient Greek writers considered the grave sounds as high, and the acute ones as low. The present mode of speaking on the subject is of more recent origin; but at what time and in what way it was introduced cannot be asserted with confidence. In the preface just referred to, it is, however, observed, that the ancient Greek custom of looking upon

the grave sounds as high and the acute as low, precisely the reverse of what is now common, continued down until the time of Boethius. It has been conjectured with some ingenuity, that this connection or association of thought among the Greeks and Romans, for it was equally prevalent among both, might have been owing to the construction of their musical instruments. The string, which sounded the grave or what we call the low tone, it has been supposed, was placed highest, and that, which gave the shrill or acute, had the lowest place. If this conjecture could be ascertained to be well founded, it would strikingly show, from what very slight causes strong and permanent associations often arise. It is hardly necessary to observe, that it is important to examine the origin and progress of such associations, in order that we may correct those erroneous and illusive notions, which will be found to be built upon them.

§. 209. Connection of the ideas of extension and colour.

There is no necessary connection between colour, as the term is commonly employed by philosophers, and extension. The word cOLOUR properly denotes a sensation in the mind; the word EXTENSION, the quality of an external material object. There is, therefore, no more natural connection, and no more analogy between the two, than there is between pain and solidity. And yet it so happens that we never have the sensation or idea of colour without at the same time associating extension with it; we find them, however different they may be in their nature, inseparable in our thoughts. This strong association is formed in consequence of our always perceiving extension at the very time, in which the sensation of colour is excited in the mind. The perception of the one, and the sensation of the other have been so long simultaneous, that we have been gradually drawn into the belief, that, on the one hand, all colour has extension, and on the other, all extension has colour. But what we call colour being merely a state of the mind, it is not possible, that it should with propriety be predicated of any external mate