Nor is it any wonder that passion should produce the opinion of injury; since otherwise it must suffer a considerable diminution, which all the passions avoid as much as possible. The removal of injury may remove the anger, without proving that the anger arises only from the injury. The harm and the justice are two contrary objects, of which the one has a tendency to produce hatred, and the other love; and 'tis according to their different degrees, and our particular turn of thinking, that either of the objects prevails and excites its proper passion. SECTION IV. OF THE LOVE OF RELATIONS. Having given a reason why several actions that cause a real pleasure or uneasiness excite not any degree, or but a small one, of the passion of love or hatred towards the actors, 'twill be necessary to show wherein consists the pleasure or uneasiness of many objects which we find by experience to produce these passions. According to the preceding system, there is always required a double relation of impressions and ideas betwixt the cause and effect, in order to produce either love or hatred. But though this be universally true, 'tis remarkable that the passion of love may be excited by only one _relation_ of a different kind, viz. betwixt ourselves and the object; or, more properly speaking, that this relation is always attended with both the others. Whoever is united to us by any connexion is always sure of a share of our love, proportioned to the connexion, without inquiring into his other qualities. Thus, the relation of blood produces the strongest tie the mind is capable of in the love of parents to their children, and a lesser degree of the same affection as the relation lessens. Nor has consanguinity alone this effect, but any other relation without exception. We love our countrymen, our neighbours, those of the same trade, profession, and even name with ourselves. Every one of these relations is esteemed some tie, and gives a title to a share of our affection. There is another phenomenon which is parallel to this, viz. that _acquaintance_, without any kind of relation, gives rise to love and kindness. When we have contracted a habitude and intimacy with any person, though in frequenting his company we have not been able to discover any very valuable quality of which he is possessed; yet we cannot forbear preferring him to strangers of whose superior merit we are fully convinced. These two phenomena of the effects of relation and acquaintance will give mutual light to each other, and may be both explained from the same principle.