In the two cases hitherto considered (legitimi and secundum tabulas) it was unlikely that the other party, who knew he was not heir, would persist in the litigation; thus bonorum possessio became more than interim possession, it had grown into an independent and impregnable interest. In this form it was employed by the praetor in favour of other persons to whom, though not heredes, it seemed equitable to give a deceased man's property, which must often have become vacans, the prey of any occupant (Gaius ii. 52-56), by default of successors whom alone the narrow system of the Twelve Tables regarded as having any title. If there were no legitimus, the possession was promised to the nearest cognates, and, failing them, to the survivor of a married couple (vir et uxor); and in these cases, there being ex hypothesi no heir to dispute the award, bonorum possessio lost its character as a merely provisional interest, and the cautio which had been required from the grantee was dispensed with. Moreover, by this development persons were benefited of whom the civil law had taken no notice, whence doubtless bonorum possessio came definitely to be regarded as an independent scheme of succession, standing in contrast with that of the Twelve Tables. The bonorum possessio of liberi, and that of contra tabulas, both of which were corrigendi iuris civilis gratia, seem to have been introduced no earlier than the fall of the Republic, though the latter may have existed from the first in favour of the praeteritus suus .or sua. Eventually, too, bonorum possessio secundum tabulas underwent important modifications. Originally, it was granted to an institutus in a will sealed by seven witnesses, whether the latter was valid iure civili or not; with this question the praetor did not concern himself, leaving it to be settled by the civil law claimant ab intestato, if there were one, bringing hereditatis petitio. After contratabular possession had been introduced, it was granted to the propounder of the will if no one claimed contra tabulas. Hadrian enacted by a rescript (Dig. 28. 3. 12. pr.) that if a will were ruptum agnatione postumi, and the postumus pre-deceased the testator, the bonorum possessor secundum tabulas should be protected against the person claiming ab intestato, unless a suus had been disinherited in the will. A rescript of M. Aurelius (Gaius ii. 119-121) further provided that bonorum possessio under a praetorian testament (septem signis signatum) should hold good even against the agnates: it availed against the institutus in a formally valid prior will only if the person instituted in the praetorian testament was also entitled ab intestato. In all other cases the intestate civil law heirs prevailed over the bonorum

possessio obtained under a praetorian will; in other words, the latter was sine re.

Savigny connects the praetorian system of succession, in origin, with the old usucapio pro herede (Gaius ii. 52-56) which the civil law regarded with approval (quod voluerunt veteres maturius hereditates adiri, ut essent qui sacra facerent, quorum illis temporibus summa observatio fuit, et ut creditores haberent, a quo suum consequerentur ' ib. 55) and of which the praetor laid hold as the startingpoint of his innovations; he gave the possession to certain persons who, it was admitted, had an equitable, though not a legal, right to the estate, and devised, in the interdict quorum bonorum, a remedy by which they could recover the deceased's property from other possessors, thus placing them in a position to become owners by usucapio; the practical assimilation of the bonorum possessor to the heres, and the introduction of the possessoria hereditatis petitio, being due to the identification of bona fide possession with bonitarian ownership. Others (e. g. Hugo) think bonorum possessio was based, in all essential points, on the ius gentium, and was in origin the system applied in the succession to aliens by the praetor peregrinus, from whose edict it was gradually transferred to the edictum urbanum. This, though a priori an attractive theory, seems untenable on account of the tenderness which the praetor almost ostentatiously showed for the civil law and the agnatic conception of kinship; a gentile system of inheritance would have been based solely on cognation. Niebuhr connects bonorum possessio with the possessio of ager publicus (p. 326 supr.), with the succession to which alone he thinks it was originally concerned; but this, as has been remarked, is irreconcileable with the very name bonorum possessio, and improbable on general grounds.

EXCURSUS V.

THE GENERAL NATURE OF OBLIGATIONS.

THE term obligatio properly indicates a legal relation between two definite persons, whereby the one (creditor, Dig. 50. 16. 11, and 12. pr.) is entitled to a certain act or forbearance on the part of the other (debitor). The contrast between it and the relation existing in the case of ownership, possession, or other legal rights, is well marked by Paulus in Dig. 44. 7. 3. pr. obligationum substantia non in eo consistit, ut aliquod corpus nostrum, aut servitutem nostram faciat, sed ut alium nobis obstringat ad dandum aliquid, vel faciendum, vel praestandum,' with which may be compared Bk. iv. 6. 1 inf. 'namque agit unus quisque aut cum eo, qui ei obligatus est . . . quo casu proditae sunt actiones in personam . . . aut cum eo agit qui nullo iure ei obligatus est, movet tamen alicui de aliqua re controversiam, quo casu proditae actiones in rem sunt.' No better explanation of this contrast can be found than Austin's exposition of the difference between rights in rem and rights in personam, the merit of which, however, is marred by his use of the term obligation to denote the duty corresponding to rights of the former as well as of the latter

class.

But though this is the proper and normal meaning of the term, obligatio is sometimes used in other senses, and more especially to express one or other limb of the relation in contradistinction to the other; thus, it signifies the right of the creditor only in the common phrase adquirere obligationem (Bk. iii. 28, Dig. 45. 1. 126. 2; 23. 3. 46: cf. Bk. ii. 2. 2 supr.), and the duty of the debitor only in Dig. 12. I. 36; 46. 1. 5. 21, ib. 3. 95. 3, as well as in the definition given in Bk. iii. 13. pr. supr. Sometimes it denotes specifically the act or event from which the relation arises, as in Cod. 11. 47. 22, Dig. 2. 14. I. 3, as well as in the expressions verborum obligatio, litterarum obligatio, etc. Again, though only a person can properly be 'obligatus,' objects which are pledged are occasionally spoken of by analogy as subject to an obligation, e.g. Bk. iii. 27. 2 supr., Dig. 20.

6. 11; 2. 14. 52. 2; 13. 7. 27, and lastly, in Cod. 4. 30. 7, the term bears the meaning of a bond or document attesting an obligation.

The immediate result of an obligatio is the partial subjection (in law) of one person's will to that of another; the partial limitation of the debitor's freedom of action in favour of the creditor. If I engage to buy 1000l. Consols, I am no longer at liberty to buy railway stock with the same money: I must take the Consols, or (which comes to the same thing) I must pay damages: 'debitor intellegitur is, a quo invito pecunia exigi potest' Dig. 50. 16. 108; the prominent conception is that expressed in the necessitate adstringimur' of the definition of obligation in the Institutes. As Savigny remarks, the relation of obligation to personal freedom resembles that of servitude to dominium: it is, as it were, so much deducted from the ideal whole. But, as he also points out, the restriction must be partial only; if a man's freedom is not merely curtailed in favour of another, but absolutely resigned, this is not obligation, but slavery.

The object or content of an obligation is an act or forbearance; the debtor is bound either to do or not to do. The nature of this act or forbearance requires some elucidation.

(1) The current Roman classification of the possible objects of obligation is that suggested by the passage of Paulus cited above, into dare, facere, and praestare: cf. Gaius iv. 2 'in personam actio est. . . cum intendimus dare, facere, praestare oportere.' Where one person is bound to convey ownership in a definite object (certum) to another, or to constitute in his favour, in a mode recognised by the civil law, a ius in re aliena, the obligation is 'dare.' By praestare seems to be meant making compensation for a wrong all other obligations, including the majority of those arising ex contractu, are 'facere.' It is obvious that this is not a scientific classification, and it originated, in point of fact, in the technicalities of pleading under the formulary system, apart from which it is not easy to understand: under Justinian it is a mere valueless survival of an older and obsolete procedure.

(2) The act or forbearance must have an appreciable money value in relation to the creditor, ea enim in obligatione consistere, quae pecunia lui praestarique possunt' Dig. 40. 7. 9. 2. This rule originated in the fact that under the formulary procedure the remedy in a personal action was always damages; there was no specific performance, and if, on the debitor's refusal to do that to which he was bound, the creditor's only means of procuring satisfaction was to obtain a pecuniary condemnation, an obligation which could not be

represented in a money value was clearly no obligation at all. There are writers, however, who deny the application of this principle under Justinian, on the ground that its original reason had disappeared along with the introduction of specific performance: others distinguish between obligations stricti iuris and bonae fidei (Bk. iv. 6. 28 inf.), holding that in the latter regard was paid to the feelings no less than to the purse of the creditor, while in the former the purse alone was considered.

(3) The object of the obligation must be possible of performance both in nature and by law (see Bk. iii. 19. 1 and notes), e. g. no duty would arise from a promise to convey a res extra commercium; but one can be validly bound to perform an act at present impossible in the event of its becoming possible (Dig. 45. 1. 98. pr); further, it must not be unlawful, Dig. 45. 1. 26, ib. 27. pr.

(4) The act or forbearance must be sufficiently definite, or at least capable of being rendered so; e. g. one cannot be bound to do just so much as and no more than one pleases, Dig. 45. I. 108. I.

The classification of obligations according to the mode in which they originate meets us in Bk. iii. 13. 2, and is spoken of in the notes to that passage; another division, of great prominence in Roman law, requires some explanation. An obligation is none the less an obligation merely because the creditor is unable to enforce it by action; there are other modes in which the duty may be discharged besides this, so that the relation fails only in one of its most ordinary incidents. Actionability is only one of such usual incidents, though perhaps the most characteristic of all, and an obligatio does not lose its legal character by reason of its absence only. Such non-actionable obligations are said to be 'natural,' in contrast with those which are 'civil,' i. e. enforceable by action; in Dig. 46. 3. 95. 4, the bond is called vinculum aequitatis, as being imposed by equity, though the precise relation of the nature' implied in a natural obligation, and the nature whose law is identified by the jurists with equity and the ius gentium, is somewhat obscure. That the jural recognition of such obligations originated in the ius gentium seems to be affirmed in Dig. 50. 17. 84. I 'is natura debet, quem iure gentium dare oportet, cuius fidem secuti sumus,' though by some writers it is ascribed to natural law in a philosophical rather than a legal sense.

Some obligations are natural ab initio; in other words, an act or event produces a natural obligation, which under other circumstances would have been civil: there is a reason why in the particular case