LIB. III, TIT. XIII.

DE OBLIGATIONIBUS.
     Nunc transeamus ad obligationes.  obligatio est iuris vinculum, quo necessitate adstringimur alicuius solvendae rei, secundum nostrae civitatis iura.
     §1. Omnium autem obligationum summa divisio in duo genera deducitur:  namque aut civiles sunt aut praetoriae.  civiles sunt, quae aut legibus constitutae aut certe iure civili comprobatae sunt.  praetoriae sunt, quas praetor ex sua iurisdictione constituit, quae etiam honorariae vocantur.
     §2. Sequens divisio in quattuor species deducitur:  aut enim ex contractu sunt aut quasi ex contractu aut ex maleficio aut quasi ex maleficio.  prius est, ut de his quae ex contractu sunt dispiciamus.  harum aeque quattuor species sunt:  aut enim re contrahuntur aut verbis aut litteris aut consensu.  de quibus singulis dispiciamus.

LIB. III, TIT. XIV.
QUIBUS MODIS RE CONTRAHITUR OBLIGATIO  .
     Re contrahitur obligatio veluti mutui datione.  mutui autem obligatio in his rebus consistit quae pondere, numero mensurave constant, veluti vino, oleo, frumento, pecunia numerata, aere, argento, auro, quas res aut numerando aut metiendo aut adpendendo in hoc damus ut accipientium fiant, et quandoque nobis non eaedem res, sed aliae eiusdem naturae et qualitatis reddantur.  unde etiam mutuum appellatum sit, quia ita a me tibi datur, ut ex meo tuum fiat. ex eo contractu nascitur actio quae vocatur condictio. 

§1. Is quoque, qui non debitum accepit ab eo qui per errorem solvit re obligatur:  daturque agenti contra eum propter repetitionem condicticia actio; nam proinde ei condici potest SI  PARET  EUM  DARE  OPORTERE  ac si mutuum accepisset.  unde pupillus, si ei sine tutoris auctoritate non debitum per errorem datum est, non tenetur indebiti condictione, non magis quam mutui datione.  sed haec species obligationis non videtur ex contractu consistere, cum is qui solvendi animo dat magis distrahere voluit negotium quam contrahere.
  §2.   Item is cui res aliqua utenda datur, id est commodatur, re obligatur et tenetur commodati actione.  sed is ab eo qui mutuum accepit longe distat:  namque non ita res datur ut eius fiat, et ob id de ea re ipsa restituenda tenetur.  et is quidem qui mutuum accepit, si quolibet fortuito casu quod accepit amiserit, veluti incendio, ruina, naufragio aut latronum hostiumve incursu, nihilo minus obligatus permanet.  at is qui utendum accepit sane quidem exactam diligentiam custodiendae rei praestare iubetur, nec sufficit ei tantam diligentiam adhibuisse quantam suis rebus adhibere solitus est, si modo alius diligentior poterit eam rem custodire:  sed propter maiorem vim maioresve casus non tenetur, si modo non huius culpa is casus intervenerit: alioquin si id quod tibi commodatum est peregre ferre tecum malueris, et vel incursu hostium praedonumve vel naufragio amiseris, dubium non est quin de restituenda ea re tenearis. commodata autem res tunc proprie intellegitur, si nulla mercede accepta vel constituta res tibi utenda data est.  alioquin mercede interveniente locatus tibi usus rei videtur:  gratuitum enim debet esse commodatum.
     § 3. Praeterea et is apud quem res aliqua deponitur re obligatur, et actione depositi, qua et ipse de ea re quam accepit restituenda tenetur.  sed is ex eo solo tenetur, si quid dolo commiserit, culpae autem nomine, id est desidiae atque neglegentiae, non tenetur:  itaque securus est qui parum diligenter custoditam rem furto amisit, quia, qui neglegenti amico rem custodiendam tradidit, suae facilitati id imputare debet.
     § 4. Creditor quoque qui pignus accepit re obligatur, qui et ipse de ea ipsa re quam accepit restituenda tenetur actione pigneraticia.  sed quia pignus utriusque gratia datur, et debitoris, quo magis ei pecunia crederetur, et creditoris, quo magis ei in tuto sit creditum, placuit sufficere, quod ad eam rem custodiendam exactam diligentiam adhiberet:  quam si praestiterit et aliquo fortuito casu rem amiserit, securum esse nec impediri creditum petere.

Title XIII. Of Obligations

Let us now pass to obligations. An obligation is a tie of law binding us to the fulfilment of something in accordance with the laws of this empire.
§ I. The principal division of all obligations is into two kinds, for they are either civil or praetorian. Civil obligations are those directly established by statute, or at least approved by the civil law. Praetorian obligations are those which the praetor or has created by his own authority; they are also called honorary.
§ 2. A further division separates them into four kinds, for they arise either from contract, or what is analogous to a contract, or from tort, or what is analogous to a tort. It will be necessary, first, to treat of those which arise from con-tract, of which again there are four kinds; for they are formed by the thing, or by words, or by writing, or by consent. We must consider each of these separately.

Title XIV. Of the modes in which an obligation is contracted by means of the thing itself.

An obligation is contracted by means of the thing itself, as in the case of a loan in kind. This contract of loan in kind applies to things which are estimated by weight, number, or measure, as, for example, wine, oil, corn, coined money, copper, silver, gold, which things we give either by counting, or measuring, or weighing them, in order that they may become the property of those receiving them, and the identical things lent are not returned to us, but others of the same nature and quality; and, hence, this is called a "mutuum", because the thing is so given by me to you that from being mine it is yours. From this contract arises action termed a "condictio".

§1. He, also, who receives a thing which is not owed to him from a person who pays it by mistake, is bound by the thing, and the "condictitia" action is available to the plaintiff against him for the recovery of the thing, for he can be sued by the personal action, "if it appear that he ought to give", just as if he had received a loan in kind. Hence, a pupil to whom, without the authorisation of his tutor, something has been paid by mistake which was not due, is not liable to a personal action, for that which is not due, any more than he would be by the giving of a loan in kind. But this kind of obligation does not seem to arise out of contract, since he who gives with the intention of paying, is rather desirous of dissolving than of forming an obligation.

§ 2. Again, he to whom something is given in order to be used, that is, lent, is bound by means of the thing itself, and is subject to the action for a specific loan. But his position is widely different from him who receives a loan in kind; for the thing is not given him in order that it may become his property, and therefore he is bound to restore the identical thing itself. And he who receives a loan in kind, if by any mischance, as, for example, by fire, by the fall of a building, by shipwreck, by the attack of thieves or enemies, he should lose what he receives, nevertheless remains bound. But he who receives a thing for use, is indeed required to employ the utmost diligence in the preservation of it, and it will not be sufficient for him to have given the same amount of care which he has been accustomed to give in respect of his own property, if a more careful person might have preserved it in safety; but he is not liable for loss occasioned by superior force, or unavoidable accident, provided only that this mischance was not due to his own fault; otherwise, if you choose to take with you on a journey the thing simply lent you to use, and you lose it by the attack of enemies or robbers, or by shipwreck, there is no doubt but that you are liable fur its restitution. A thing is properly said to be lent in specie when the thing is given you to be used, no recompense being received or agreed upon; otherwise, if there is any recompense, the use of the thing is held to be hired out to you, for a loan in specie must be gratuitous.

§ 3. Further, he with whom something is deposited is bound by means of the thing itself, and liable to the action of deposit, for he also is liable for the restitution of the identical thing which he received. He is, however, only liable on the ground of having committed fraud, and is not liable under the head of failure of duty, that is, for carelessness or negligence. He is therefore safe, front whom a thing deposited with him, which he has not kept sufficiently carefully, has been stolen, for he who delivers a thing into the custody of a careless friend, should impute its loss to his own imprudence.

§ 4. The creditor, also, who receives a pledge is bound by means of the thing itself, and is liable by the action of pledge for the restoration of the identical thing which he receives. But since a pledge is given in the interest of both parties, of the debtor that he may the more readily borrow money, and of the creditor that the debt due to him may be better secured, it has been held to be sufficient if he employ the utmost diligence about the custody of the thing, and if he has done this, and he lose the thing by some accident, he is safe-, and is not prevented claiming the sum advanced.

(Mears, T. Lambert, trans. The Institutes of Gaius and Justinian. London: Stevens, 1882.)