A third class of laws.
Let us proceed to consider the laws of our nature relative to the association of ideas, and the formation of habits.
These relative to the association of ideas and habits.
There are two things very remarkable in our nature; “The association of ideas, or the difficulty with which ideas that have been often presented to the mind together are afterwards disjoined;” and, “The formation of habits by repeated acts; or a facility in doing, and a propension to reiterate the same action contracted by frequent doing it.”
Both these take their rise from one principle.
These two effects are very similar or like: they both include in their nature a certain kind of cohesion with the mind, formed by reiterated conjunction or co-existence between objects really separate and distinct from one another; i.e. that do not necessarily co-exist, or are not naturally parts of one<82> whole. And as they are like to one another, so they must go together; or neither of them can take place in a mind without the other. If habits are contracted by repeated acts, ideas will be joined or mixed by repeated concurrence: and reciprocally, if ideas contract a sort of coherence by being often joined, habits must be formed by frequent repetition of acts. This is plain. For,
They must both go together.
I. Unless the mind were so framed, that ideas frequently presented together to it, should afterwards naturally continue to recal one another, to blend or return together, habits could not be contracted. Thus, for instance, the habit of taking snuff, could not take place, did not the returns of certain perceptions recal the idea and desire of snuff. And the case must be the same with regard to all other habits; for all habits, of whatever kind, operate the same way. The reason is, because all actions of the mind are excited by and employed about ideas; and an action cannot be reiterated, unless its object and motive be revived. A propension to any action is nothing else but the frequent return of a certain desire, which necessarily supposes the equally frequent returns of the ideas which excite it, and are the subject of it: and facility in acting, in like manner, supposes the easy and quick return of the ideas that induce to the action, and are its subject. The formation of habits therefore supposes the association of ideas to take place. But,
II. If association of ideas take place, habits must necessarily be formed by repeated acts. For, if we attend to the matter strictly, we shall immediately find, that the whole course of what is called action, or a series of action, (the wills to act or make efforts to act alone excepted) is nothing but a train of passive perceptions or ideas. But ideas, as often as they return, must excite certain affections, and the<83> affections which lead to action, must, as often as they are revived, dispose and excite to act; or, in other words, produce will to act. And if will to act be successful, the train of perceptions called action, must succeed; and, by frequently succeeding in this manner, cohesion or association must be formed of this kind, that is, associations that terminate in action must be contracted.
Those effects called the association of ideas and formation of habits, do therefore resolve themselves into the same general law or principle in our nature, which may be called thea law of custom.
But whatever the cause be, one or more, these effects are certain.
Both proceed from a most useful principle.
A principle that may justly be called the law of perfection.
But, whether they are reduced to one or different principles, nothing can be more certain; than that ideas are associated by being frequently conjoined, in such a manner, that it is not easy to prevent their mixing so together as to make one perception, or, at least, their coherence and joint return to the mind; and that habits are formed by repeated acts. Now, nothing can be of greater use in our frames, than the principle or principles from which these effects arise. For, what can be more evident, than that were we not so constituted, we could not attain to perfection in any science, art, or virtue? It<84> would not be in our power to join and unite ideas at our pleasure, to recal past ones, or to lay up a stock of knowledge in our minds to which we could have recourse upon any occasion, and bring forth, as it were, ready money for present use. Nor would it be in our power by all our reiterated acts to become more ready, alert, and expeditious in performing any operation than at our first attempt; but, in every thing, and on every emergence, after ever so much past labour, all our work would constantly be to begin again. In one word, habits are perfected faculties: or faculties perfected by exercise are habits. So that the law of habits is really the law of improvement to perfection; and is therefore a most excellent, a most useful law.
All this is very obvious. But so extremely, so universally useful is this part of our frame, that its well worth while to examine it more fully, and take a larger view of its effects. We shall therefore first consider some of the principal phenomena belonging to the association of ideas.
I. And, in order to proceed distinctly, let us be sure that we carry along with us a clear idea of the thing itself.
Associated ideas defined, and distinguished from complex ideas, &c.
Sensible ideas or qualities, which by their co-existence make the same object, (as, for instance, it is a particular shape, size, colour, taste, and other combined qualities in the same subject that make a peach) are not said to be associated, because they naturally and really co-exist, or naturally and really make the same object.a
Nor is the complex idea which we have of a peach, after having tasted several, that is immediately excited in us by the sight of it, before we touch or taste it, called an associated idea; tho’ the greater part of it consists of ideas not perceived, but imagined;<85> because the qualities imagined do really belong to the peach. We are much indebted to the wonderful quickness of our fancy, in adding several qualities on such occasions to those really perceived, to compleat our ideas. But such supplies, by the imagination to any of our sensible ideas, as intimately as they unite and blend with them, are not called ideas of association, because whatever is thus added by the imagination to the perceptions of sense, is a copy of a sensible quality really appertaining to the object perceived.
But, if a peach having been often presented to us on agreeable occasions, should become ever afterwards exceedingly more desireable than before, by recalling to our mind these agreeable circumstances; then is the whole idea of a peach that thus excites our desire and greatly pleases us, compounded of the real qualities of a peach, and of these other delightful ideas not belonging to it, but suggested to, or excited in our imagination by it. Or contrariwise, if a peach which was formerly very agreeable, having been frequently presented to us on melancholly occasions, shall ever afterwards recal to our minds these disagreeable circumstances, and so become hateful to us; then the idea of a peach is compounded of uneasy ideas that overballance all its good and formerly desireable qualities, or that so entirely possess the mind, that there is no room for these qualities to enter into it.
Almost all our ideas have something in them of the associated kind.
In both these and all such cases our ideas are made up of real and associated ingredients, or compounded of parts, some of which do really belong to the object, and others do not, but are added by the mind itself: they are made up of ingredients that have no natural or necessary coherence, but that cohere or are mixed by customary association.
III. The instances that have been given, in order to determine the meaning of association, are indeed<86> but trifling and of little moment. But the thing itself in its full extent is of the greatest consequence. For if we consider our ideas with due attention, and take the trouble to analyse them, we shall find that very few, if any of the ideas, that excite our warmest and keenest affections, are quite free from associated parts. The greater number of our perceptions, however agreeable or disagreeable, are of