It is here we must seek for a solution of the difficulty above-mentioned, why any object ever excites pure love or hatred, and does not always produce respect or contempt, by a mixture of humility or pride. No quality in another gives rise to humility by comparison, unless it would have produced pride by being placed in ourselves; and vice versa no object excites pride by comparison, unless it would have produced humility by the direct survey. This is evident, objects always produce by comparison a sensation directly contrary to their original one. Suppose, therefore, an object to be presented, which is peculiarly fitted to produce love, but imperfectly to excite pride; this object, belonging to another, gives rise directly to a great degree of love, but to a small one of humility by comparison; and consequently that latter passion is scarce felt in the compound, nor is able to convert the love into respect. This is the case with good nature, good humour, facility, generosity, beauty, and many other qualities.

These have a peculiar aptitude to produce love in others; but not so great a tendency to excite pride in ourselves: For which reason the view of them, as belonging to another person, produces pure love, with but a small mixture of humility and respect. It is easy to extend the same reasoning to the opposite passions.

Before we leave this subject, it may not be amiss to account for a pretty curious phænomenon, viz, why we commonly keep at a distance such as we contemn, and allow not our inferiors to approach too near even in place and situation. It has already been observed, that almost every kind of idea is attended with some emotion, even the ideas of number and extension, much more those of such objects as are esteemed of consequence in life, and fix our attention. It is not with entire indifference we can survey either a rich man or a poor one, but must feel some faint touches at least, of respect in the former case, and of contempt in the latter. These two passions are contrary to each other; but in order to make this contrariety be felt, the objects must be someway related; otherwise the affections are totally separate and distinct, and never encounter. The relation takes place wherever the persons become contiguous; which is a general reason why we are uneasy at seeing such disproportioned objects, as a rich man and a poor one, a nobleman and a porter, in that situation.

This uneasiness, which is common to every spectator, must be more sensible to the superior; and that because the near approach of the inferior is regarded as a piece of ill-breeding, and shews that he is not sensible of the disproportion, and is no way affected by it. A sense of superiority in another breeds in all men an inclination to keep themselves at a distance from him, and determines them to redouble the marks of respect and reverence, when they are obliged to approach him; and where they do not observe that conduct, it is a proof they are not sensible of his superiority. From hence too it proceeds, that any great difference in the degrees of any quality is called a distance by a common metaphor, which, however trivial it may appear, is founded on natural principles of the imagination. A great difference inclines us to produce a distance. The ideas of distance and difference are, therefore, connected together.

Connected ideas are readily taken for each other; and this is in general the source of the metaphor, as we shall have occasion to observe afterwards.

Of all the compound passions, which proceed from a mixture of love and hatred with other affections, no one better deserves our attention, than that love, which arises betwixt the sexes, as well on account of its force and violence, as those curious principles of philosophy, for which it affords us an uncontestable argument. It is plain, that this affection, in its most natural state, is derived from the conjunction of three different impressions or passions, viz. The pleasing sensation arising from beauty; the bodily appetite for generation; and a generous kindness or good-will. The origin of kindness from beauty may be explained from the foregoing reasoning. The question is how the bodily appetite is excited by it.

The appetite of generation, when confined to a certain degree, is evidently of the pleasant kind, and has a strong connexion with, all the agreeable emotions. Joy, mirth, vanity, and kindness are all incentives to this desire; as well as music, dancing, wine, and good cheer. On the other hand, sorrow, melancholy, poverty, humility are destructive of it. From this quality it is easily conceived why it should be connected with the sense of beauty.

But there is another principle that contributes to the same effect. I have observed that the parallel direction of the desires is a real relation, and no less than a resemblance in their sensation, produces a connexion among them. That we may fully comprehend the extent of this relation, we must consider, that any principal desire may be attended with subordinate ones, which are connected with it, and to which if other desires are parallel, they are by that means related to the principal one. Thus hunger may oft be considered as the primary inclination of the soul, and the desire of approaching the meat as the secondary one; since it is absolutely necessary to the satisfying that appetite. If an object, therefore, by any separate qualities, inclines us to approach the meat, it naturally encreases our appetite; as on the contrary, whatever inclines us to set our victuals at a distance, is contradictory to hunger, and diminishes our inclination to them.

Now it is plain that beauty has the first effect, and deformity the second: Which is the reason why the former gives us a keener appetite for our victuals, and the latter is sufficient to disgust us at the most savoury dish that cookery has invented. All this is easily applicable to the appetite for generation.

From these two relations, viz, resemblance and a parallel desire, there arises such a connexion betwixt the sense of beauty, the bodily appetite, and benevolence, that they become in a manner inseparable: And we find from experience that it is indifferent which of them advances first; since any of them is almost sure to be attended with the related affections. One, who is inflamed with lust, feels at least a momentary kindness towards the object of it, and at the same time fancies her more beautiful than ordinary; as there are many, who begin with kindness and esteem for the wit and merit of the person, and advance from that to the other passions. But the most common species of love is that which first arises from beauty, and afterwards diffuses itself into kindness and into the bodily appetite. Kindness or esteem, and the appetite to generation, are too remote to unite easily together. The one is, perhaps, the most refined passion of the soul; the other the most gross and vulgar.

The love of beauty is placed in a just medium betwixt them, and partakes of both their natures: From whence it proceeds, that it is so singularly fitted to produce both.

This account of love is not peculiar to my system, but is unavoidable on any hypothesis. The three affections, which compose this passion, are evidently distinct, and has each of them its distinct object. It is certain, therefore, that it is only by their relation they produce each other. But the relation of passions is not alone sufficient. It is likewise necessary, there should be a relation of ideas.

The beauty of one person never inspires us with love for another. This then is a sensible proof of the double relation of impressions and ideas. From one instance so evident as this we may form a judgment of the rest.

This may also serve in another view to illustrate what I have insisted on concerning the origin of pride and humility, love and hatred. I have observed, that though self be the object of the first set of passions, and some other person of the second, yet these objects cannot alone be the causes of the passions; as having each of them a relation to two contrary affections, which must from the very first moment destroy each other. Here then is the situation of the mind, as I have already described it. It has certain organs naturally fitted to produce a passion; that passion, when produced, naturally turns the view to a certain object. But this not being sufficient to produce the passion, there is required some other emotion, which by a double relation of impressions and ideas may set these principles in action, and bestow on them their first impulse.

This situation is still more remarkable with regard to the appetite of generation. Sex is not only the object, but also the cause of the appetite. We not only turn our view to it, when actuated by that appetite; but the reflecting on it suffices to excite the appetite. But as this cause loses its force by too great frequency, it is necessary it should be quickened by some new impulse; and that impulse we find to arise from the beauty of the person; that is, from a double relation of impressions and ideas. Since this double relation is necessary where an affection has both a distinct cause, and object, how much more so, where it has only a distinct object, without any determinate cause?

But to pass from the passions of love and hatred, and from their mixtures and compositions, as they appear in man, to the same affections, as they display themselves in brutes; we may observe, not only that love and hatred are common to the whole sensitive creation, but likewise that their causes, as above-explained, are of so simple a nature, that they may easily be supposed to operate on mere animals. There is no force of reflection or penetration required. Every thing is conducted by springs and principles, which are not peculiar to man, or any one species of animals. The conclusion from this is obvious in favour of the foregoing system.

Love in animals, has not for its only object animals of the same species, but extends itself farther, and comprehends almost every sensible and thinking being. A dog naturally loves a man above his own species, and very commonly meets with a return of affection.

As animals are but little susceptible either of the pleasures or pains of the imagination, they can judge of objects only by the sensible good or evil, which they produce, and from that must regulate their affections towards them. Accordingly we find, that by benefits or injuries we produce their love or hatred; and that by feeding and cherishing any animal, we quickly acquire his affections; as by beating and abusing him we never fail to draw on us his enmity and ill-will.

Love in beasts is not caused so much by relation, as in our species; and that because their thoughts are not so active as to trace relations, except in very obvious instances. Yet it is easy to remark, that on some occasions it has a considerable influence upon them. Thus acquaintance, which has the same effect as relation, always produces love in animals either to men or to each other. For the same reason any likeness among them is the source of affection. An ox confined to a park with horses, will naturally join their company, if I may so speak, but always leaves it to enjoy that of his own species, where he has the choice of both.

The affection of parents to their young proceeds from a peculiar instinct in animals, as well as in our species.