the one is entitled to claim an act or forbearance from the other. The one, or creditor, has a right in personam, the other, or debtor, owes to him a relative duty; both right and duty are conceived as obligationes, or as correlative parts of a single obligatio; but it is the right, or creditor side, alone which is a res incorporalis, and owing to which this department of law falls under the head of 'res' at all.

This is not so clear and above doubt as never to have been questioned. The position of obligations between the law of Inheritance and the law of Actions has led Hugo and others to regard them as a portion of the latter rather than of the ius quod ad res pertinet; a theory to some extent countenanced by the fact that in the Digest (de obligationibus et actionibus, 44. 7) and Code (4. 10) actions and obligations are treated together, and by the technical meaning of 'actio' as action in personam, in contrast with 'petitio' or action in rem, Dig. 44. 7. 28; 50. 16. 178. 2. It has even been attempted to support this view by a statement of Theophilus in his commentary on Tit. 13. pr. of this book, where he says, 'Now that we have spoken of persons and of things, we ought logically to treat of actions; but this arrangement, i.e. the treating of obligations first, is not inexcusable, for in discussing obligations one is implicitly discussing actions also, of which they are the mothers.' But it is clear from his remarks on Bk. iv. 6. pr., that Theophilus is preferring a fourfold division of the law, making obligationes a fourth and independent department intermediate between res and actiones; and this cannot convince us that Justinian in his Institutes intended to depart from the arrangement of Gaius: for although, had we the Institutes alone, a reasonable suspicion might be justified by the fact that obligations are partly treated in the third book, which no one doubts begins with res, and partly in the fourth, which no one doubts ends with actiones, yet this is removed by our knowledge that Gaius concludes the subject of obligations in his third book, and devotes the whole of the fourth to actions. Indeed, the enumeration of obligations among res incorporales in Bk. ii. 2. 2, is sufficient proof in itself of the wrongness of Hugo's theory.

The acts or events which give rise to this kind of legal relation called obligatio are of course different from one another in character, but they may be grouped with tolerable correctness in two principal and two subordinate classes. One of the former, which is prominent in all developed systems of law, is agreement; the other is delict, which may here be defined with sufficient accuracy as wrong other than breach of contract. But there are obligations which take their

rise in circumstances in which the person held liable has neither entered into an agreement with the other party to the relation, nor committed a delict against him, in the technical Roman sense of the word. In these circumstances, however, it is always possible to find more or less of analogy with one or other of the main sources of obligations: so that the four classes of acts or events referred to are in Title 13. 2 determined as contract, quasi-contract, delict, and quasi-delict.

Not all agreements are contracts; in other words, it does not follow that because a person has given a promise he can be compelled to keep it by action at law. Primitive law, it would seem, at first enforces promises only when they are accompanied by some striking and. solemn formality: formal contracts are actionable before those which are formless. There were three kinds of form known to the Roman system in which a promise might be clothed so as to be enforceable at law, two of which, nexum and expensilatio or litterae, were obsolete long before Justinian, though there is some notice of the second, and a lame attempt to represent it as still existing, in Title 21. The third was stipulatio, the expression of the agreement in a solemn question and answer, which, however, by a gradual process of change had in Justinian's own age been so stripped of its original characteristics, that it is only by an abuse of language that it can be described as a formal contract at all. But quite early in the history of the Roman Law this requirement of form, coupled with the inability of aliens to employ it, was found so to hamper the freedom of commercial intercourse, and to interfere so largely with the transactions of everyday life, that certain contracts of the ius gentium were added to the small circle already recognised: two kinds of loan, deposit, and pledge were held to be actionable merely in virtue of delivery by one party to the other, whence the obligation was said to be imposed 're,' while sale, hire, partnership, and agency could now be contracted by the mere consent of the parties without the necessity of any formality, and consequently were called 'consensual' contracts. All of these subjects are treated at considerable length in this part of the Institutes. The contracts which are called Real-mutuum, or loan for consumption, commodatum, or loan for use, deposit, and pledge-because the 'causa' through which they become actionable is 'res' or delivery, are discussed in Title 14. Stipulation receives a consideration commensurate with the importance of the part it played in so large a proportion of the daily dealings between man and man. In Title 15

a historical account is given of the changes which took place in the form of the contract between the earliest and the latest phases of the

Roman Law; alternatives are soon tolerated for the old sacramental terms, which none could use but Roman citizens, and thus peregrini are enabled to avail themselves of this universally applicable contract form; the question and answer are allowed to be expressed in other languages than Latin, and the strict and literal correspondence between them is no longer regarded as indispensable; finally, that they should be oral, and so require the presence of the parties, is found to be an inconvenient and unnecessary condition, and the original solemnities of stipulation have dwindled into a written memorandum of a promise fictitiously represented as having been made in answer to a preceding question. Some minor matters, such as the qualification of such promises by time and conditions, and the use of penalties under many circumstances, are touched upon in the same Title. Joint and several liability, or as the modern civilians term it, Correality or Solidarity, is briefly noticed in Title 16, because whenever it arose ex contractu it usually took the form of stipulation. In Title 17 we have a statement of the effect of promises made by stipulation to a slave: a subject treated in relation to obligations generally, and to persons in patria as well as dominica potestas, in Title 28. Title 18 relates to a classification of stipulations according as they are based upon genuine consent, or are forced upon a party by a judge or magistrate, and so reminds the reader of the traditional division of contracts in English law into 'contracts of record' and contracts in the ordinary sense of the term. This is followed in Title 19 by an ill-arranged exposition of circumstances which affect the validity of contracts in general, and of stipulations in particular, such as illegality, impossibility, infancy, and weakness of intellect; and here too we have a precise statement of the jural maxim that an obligation is a tie between ascertained parties, incapable of conferring rights or imposing liabilities on others who are not parties to it themselves, and Justinian's own repeal of some previously existing rules invalidating stipulations, but out of harmony with the modern principle that 'consent is the essence of contract.' Title 20 relates to fideiussio, a form of suretyship effected by stipulation; other modes in which this important relation could be established are described in the notes to this Title and Title 26. Title 21, professedly on literal contract, tells us little more than that literal contract in the true sense (expensilatio) had long been obsolete, though it also touches a subject upon which more is said in Excursus VIII inf. -the defence of no consideration. The five succeeding Titles contain a very full treatment of the important class of contracts called consensual. In the first, their characteristic features, as contrasted

with those of stipulation and Real contract, are tersely noticed. Sale is considered in Title 23; the principles relating to the moment at which the contract is held to be concluded, the necessity of the price being fixed and in money, and the 'periculum rei,' are clearly set forth, together with one or two changes made in the law by Justinian himself, and an incidental notice of a subject touched upon elsewhere in this part of the book, the doctrine of negligence in contractual relations. Locatio conductio, or hire, is discussed upon much the same lines in Title 24, and in Title 25 are described the chief forms of partnership, the relations of partners inter se, and the modes in which this contract is determined. Title 26 is upon the subject of agency, the species of which are classified according to the variations in the persons benefited by the agent's commission; the modes in which that commission terminates, and the reciprocal duties of agent and principal, are also noticed. The question which is of so much practical importance in modern law as to the capacity of the agent to bind and entitle his principal is passed over in silence, but is treated at some length in Excursus IX inf. Quasi-contractual obligations are illustrated in Title 27 by negotiorum gestio, indebiti solutio, joint ownership and inheritance, and the relations of guardian and ward, heir and legatee; and Title 29 deals with the discharge of obligations, and more particularly of those which arise ex contractu; the chief modes described are performance, accord and satisfaction, release, and substituted agreement. Assignment, of which some treatment might have been looked for, is discussed in the Excursus (V) on the general nature of obligations.

The description here given of the Roman contract system-if we may use that expression to indicate the aggregate of actionable agreements is somewhat misleading. It must not be supposed that in the time of Justinian, or even of Gaius, no agreement was ground to support an action which was neither expressed in the form of stipulation, nor belonged to one or other of the classes of Real and Consensual contracts. There had been a considerable advance in two directions since the time when usage had restricted the term 'contract' to denote the four classes of agreement enumerated in Title 13. Between the establishment of the Empire and the age of the last great classical jurists the principle of the Real contracts had received a great development by the recognition of the rule, that where one party to any bilateral agreement whatsoever had performed what he had undertaken, he had always a remedy by action to enforce performance by the other. This great group of so-called 'innominate '

contracts is treated in a note on Title 14. 4. New contracts, though not so called, which in effect were consensual, were called into existence at different times by the Edict and imperial action; hypotheca (pp. 318-320 supr.), constitutum (note on iii. 20. 8), and receptum nautarum, etc. (note on iv. 5. 3) are examples of the former; emphyteusis (pp. 313-315 supr.) and donatio (ii. 7) of the latter. And lastly, though this matter is disputed (Excursus V), it may be true that from the theory of 'natural' obligation every agreement whatsoever came to receive all the legal attributes possessed by even the oldest of the Roman contracts, except that of exposing the promisor to an action for the enforcement of his promise.