To make this more evident, consider, that though the rules of justice are established merely by interest, their connexion with interest is somewhat singular, and is different from what may be observed on other occasions.  A single act of justice is frequently contrary to public interest; and were it to stand alone, without being followed by other acts, may, in itself, be very prejudicial to society.  When a man of merit, of a beneficent disposition, restores a great fortune to a miser, or a seditious bigot, he has acted justly and laudably, but the public is a real sufferer.  Nor is every single act of justice, considered apart, more conducive to private interest, than to public; and it is easily conceived how a man may impoverish himself by a signal instance of integrity, and have reason to wish, that with regard to that single act, the laws of justice were for a moment suspended in the universe.  But however single acts of justice may be contrary, either to public or private interest, it is certain, that the whole plan or scheme is highly conducive, or indeed absolutely requisite, both to the support of society, and the well-being of every individual.  It is impossible to separate the good from the ill.  Property must be stable, and must be fixed by general rules.  Though in one instance the public be a sufferer, this momentary ill is amply compensated by the steady prosecution of the rule, and by the peace and order, which it establishes in society.  And even every individual person must find himself a gainer, on ballancing the account; since, without justice. society must immediately dissolve, and every one must fall into that savage and solitary condition, which is infinitely worse than the worst situation that can possibly be supposed in society.  When therefore men have had experience enough to observe, that whatever may be the consequence of any single act of justice, performed by a single person, yet the whole system of actions, concurred in by the whole society, is infinitely advantageous to the whole, and to every part; it is not long before justice and property take place.  Every member of society is sen sible of this interest:  Every one expresses this sense to his fellows, along with the resolution he has taken of squaring his actions by it, on condition that others will do the same.  No more is requisite to induce any one of them to perform an act of justice, who has the first opportunity.  This becomes an example to others.  And thus justice establishes itself by a kind of convention or agreement; that is, by a sense of interest, supposed to be common to all, and where every single act is performed in expectation that others are to perform the like.  Without such a convention, no one would ever have dreamed, that there was such a virtue as justice, or have been induced to conform his actions to it.  Taking any single act, my justice may be pernicious in every respect; and it is only upon the supposition. that others are to imitate my example, that I can be induced to embrace that virtue; since nothing but this combination can render justice advantageous, or afford me any motives to conform my self to its rules.