It is the thesis of this book that the members of the public, who are the spectators of action, cannot successfully intervene in a controversy on the merits of the case. They must judge externally, and they can act only by supporting one of the interests directly involved. It follows that the public interest in a controversy cannot turn upon the specific issue. On what, then, does it turn? In what phase of the controversy can the public successfully interest itself? Only when somebody objects does the public know there is a problem; when nobody any longer objects there is a solution. For the public, then, any rule is right which is agreeable to all concerned. It follows that the public interest in a problem is limited to this: that there shall be rules, which means that the rules which prevail shall be enforced, and that the unenforceable rules shall be changed according to a settled rule. The public’s opinion that John Smith should or should not do this or that is immaterial; the public does not know John Smith’s motives and needs, and is not concerned with them. But that John Smith shall do what he has promised to do is a matter of public concern, for unless the social contracts of men are made, enforced and revised according to a settled rule, social organization is impossible. Their conflicting purposes will engender unending problems unless they are regulated by some system of rights and duties. The interest of the public is not in the rules and contracts and customs themselves but in the maintenance of a régime of rule, contract and custom. The public is interested in law, not in the laws; in the method of law, not in the substance; in the sanctity of contract, not in a particular contract; in understanding based on custom, not in this custom or that. It is concerned in these things to the end that men in their active affairs shall find a _modus vivendi_; its interest is in the workable rule which will define and predict the behavior of men so that they can make their adjustments. The pressure which the public is able to apply through praise and blame, through votes, strikes, boycotts or support can yield results only if it reinforces the men who enforce an old rule or sponsor a new one that is needed.