THE NATURE OF AGENCY. 513 Professor Langdell, in a striking passage in his treatise on equity pleading, calls attention to a limitation upon the power of common law courts, as distinguished from courts of equity. He says : — "They cannot deal with a controversy to which there are more than two parties or two sets of parties. The contract of suretyship will serve as an illustration of this. To such a contract, in its simplest form, there are three parties, viz., the creditor, the principal debtor, and the surety; and no two of them are united either in interest or obligation. No more than two of them, therefore, can be parties to any action at law. If there are several sureties the case is much worse ; for though they may all be sued at law by the creditor, if their obligation be joint, yet, in any con- troversy with the debtor in which they are all interested, the law can afford no remedy ; for only one of them can be a party to an action by or against the debtor. In other words, a court of law can only entertain a controversy between the debtor and one surety. So, if a controversy arises between the several sureties, a court of law is equally powerless, as it can only entertain a controversy between two of them." ^ This limitation upon the power of common law courts has unfortunately delayed a proper recognition of the complex char- acter of many relations which have come before them for determi- nation. By reason of the presence of only two parties, such relations have been treated as bilateral, and as capable of deter- mination without the presence of other parties, when they have been in fact trilateral, or even multilateral. It is very frequently the case that such a method of treatment is practically possible and, for the sake of convenience, justifiable ; but by neglecting the parties not before them the courts have been at times misled as to the true character of the relation with which they were dealing. The famous New York case of Lawrence v. Fox,^ and the contro- versies which have raged over it, excellently illustrate the difficul- agency which he has in mind is one in which three persons are involved as parties, while it is otherwise in his mind with the relations of master and servant. He was misled, however, into a false classification on the basis of the difference between a contract and a tort. It will be readily seen that the source of his error was his failure to understand the relation between the principal and the third party, for all the illus- trations of agency which he gives involve three persons. Thus he says: "The law governing the one belongs, therefore, to that branch of the law of obligation having to do with contracts, or torts springing from contracts, as deceit. The law governing the other belongs to that branch of the law of obligation having to do with torts generally." Ibid. His exception of the tort of deceit shows how close he was to the distinction between bilateral and trilateral relations. 1 Langdell, Equity Pleading (2 ed.), § 41. 2 20 N. Y. 268 (1869).
