There is another consideration (and that probably the principal one) to be taken into the account in explaining the origin and growth of our selfish habits, which is perfectly consistent with the foregoing theory, and evidently arises out of it. There is naturally, then, no essential difference between the motives by which I am impelled to the pursuit of my own good or that of others: but though there is not a difference in kind, there is one in degree. We know better what our own future feelings will be than what those of others will be in a like case. We can apply the materials afforded us by experience with less difficulty and more in a mass in making out the picture of our future pleasures and pains, without frittering them away or destroying their original sharpnesses: in a word, we can imagine them more plainly, and must therefore be more interested in them. This facility in passing from the recollection of my former impressions to the anticipation of my future ones makes the transition almost imperceptible, and gives to the latter an apparent reality and presentness to the imagination, to a degree in which the feelings of others can scarcely ever be brought home to us. It is chiefly from this greater readiness and certainty with which we can look forward into our own minds than out of us into those of other men, that that strong and uneasy attachment to self, which often comes at last to overpower every generous feeling, takes its rise; not, as I think I have shown, from any natural and impenetrable hardness of the human heart, or necessary absorption of all its thoughts and purposes in a blind exclusive feeling of self-interest. It confirms this account, that we constantly are found to feel for others in proportion as we know from long acquaintance with the turn of their minds, and events of their lives, ‘the hair-breadth scapes’ of their travelling history, or ‘some disastrous stroke which their youth suffered,’ what the real nature of their feelings is; and that we have in general the strongest attachmentto our immediate relatives and friends, who from this intercommunity of thoughts and feelings may more truly be said to be a part of ourselves than from even the ties of blood. Moreover, a man must be employed more usually in providing for his own wants and his own feelings than those of others. In like manner he is employed in providing for the immediate welfare of his family and connexions much more than in providing for the welfare of those who are not bound by any positive ties. And we accordingly find that the attention, time, and pains bestowed on these several objects give him a proportionable degree of anxiety about, and attachment to his own interest, and that of those connected with him; but it would be absurd to conclude that his affections are therefore circumscribed by a natural necessity within certain impassable limits, either in the one case or the other. It should not be forgotten here that this absurd opinion has been very commonly referred to the effects of natural affection as it has been called, as well as of self-interest; parental and filial affection being supposed to be originally implanted in the mind by the ties of nature, and to move round the centre of self-interest in an orbit of their own, within the circle of our families and friends. This general connexion between the habitual pursuit of any object and our interest in it, will account for the well-known observation, that the affection of parents to children is the strongest of all others, frequently overpowering self-love itself. This fact does not seem easily reconcilable to the doctrine that the social affections are all of them ultimately to be deduced from association, or the reputed connexion of immediate selfish gratification with the idea of some other person. If this were strictly the case we must feel the strongest attachment to those from whom we had received, instead of those to whom we had done, the greatest number of kindnesses, or where the greatest quantity of actual enjoyment had been associated with an indifferent idea. Junius has remarked that friendship is not conciliated by the power of conferring benefits, but by the equality with which they are received and may be returned.
I have hitherto purposely avoided saying any thing on the subject of our physical appetites and the manner in which they may be thought to affect the principle of the foregoing reasonings. They evidently seem at first sight, to contradict the general conclusion which I have endeavoured to establish, as they all of them tend either exclusively or principally to the gratification of the individual, and at the same time refer to some future or imaginary object, as the source of this gratification. The impulse which they give to the will is mechanical, and yet this impulse, blind as it is, constantly tends to and coalesces with the pursuit of some rational end. That is, hereis an end aimed at, the desire and regular pursuit of a known good, and all this produced by motives evidently mechanical, and which never impel the mind but in a selfish direction: it makes no difference in the question whether the active impulse proceed directly from the desire of positive enjoyment, or a wish to get rid of some positive uneasiness. I should say then that, setting aside what is of a purely physical nature in the case, the influence of appetite over our volitions may be accounted for consistently enough with the foregoing hypothesis, from the natural effects of a particularly irritable state of bodily feeling, rendering the idea of that which will heighten and gratify its susceptibility of pleasurable feeling, or remove some painful feeling, proportionably vivid, and the object of a more vehement desire than can be excited by the same idea, when the body is supposed to be in a state of indifference, or only ordinary sensibility to that particular kind of gratification. Thus the imaginary desire is sharpened by constantly receiving supplies of pungency, from the irritation of bodily feeling, and its direction is at the same time determined according to the bias of this new impulse; first, indirectly by having the attention fixed on our own immediate sensation; secondly, because that particular gratification, the desire of which is increased by the pressure of physical appetite, must be referred primarily and by way of distinction to the same being, by whom the want of it is felt, that is, to myself. As the actual uneasiness which appetite implies can only be excited by the irritable state of my own body, so neither can the desire of the correspondent gratification subsist in that intense degree, which properly constitutes appetite, except when it tends to relieve that very same uneasiness by which it was excited, as in the case of hunger. There is in the first place the strong mechanical action of the nervous and muscular systems co-operating with the rational desire of my own belief, and forcing it its own way. Secondly, this state of uneasiness grows more and more violent, the longer the relief which it requires is withheld from it: hunger takes no denial, it hearkens to no compromise, is soothed by no flattery, tired out by no delay. It grows more importunate every moment, its demands become larger the less they are attended to. The first impulse which the general love of personal ease receives from bodily pain will give it the advantage over my disposition to sympathise with others in the same situation with myself, and this difference will be increasing every moment, till the pain is removed. Thus, if I at first, either through compassion or by an effort of the will, am regardless of my own wants, and wholly bent upon satisfying the more pressing wants of my companions, yet this effort will at length become too great, and I shall be incapable of attending to any thing but the violence of myown sensations, or the means of alleviating them. It would be easy to show from many things that mere appetite (generally, at least, in reasonable beings) is but the fragment of a self-moving machine, but a sort of half organ, a subordinate instrument even in the accomplishment of its own purposes; that it does little or nothing without the aid of another faculty to inform and direct it. Before the impulses of appetite can be converted into the regular pursuit of a given object, they must first be communicated to the understanding, and modify the will through that. Consequently, as the desire of the ultimate gratification of the appetite is not the same with the appetite itself, that is mere physical uneasiness, but an indirect result of its communication to the thinking or imaginative principle, the influence of appetite over the will must depend on the extraordinary degree of force and vividness which it gives to the idea of a particular object; and we accordingly find that the same cause which irritates the desire of selfish gratification, increases our sensibility to the same desires and gratification in others, where they are consistent with our own, and where the violence of the physical impulse does not overpower every other consideration.