1Ulpianus, On the Edict, Book XXIX. An action is very properly granted against a master for the entire amount, on the ground that he has authorized a contract; for, to a certain extent, a contract is entered into with the party who ordered it to be made. 1Ad Dig. 15,4,1,1Windscheid: Lehrbuch des Pandektenrechts, 7. Aufl. 1891, Bd. II, § 482, Note 12.Authority must, however, be understood, whether anyone gives it in the presence of a witness, or by a letter, or verbally, or by a messenger, or whether the authority was given in a specified contract, or in general terms; and therefore, if a party made a statement as follows: “Transact what business you desire with my slave Stichus, at my risk,” he is held to have directed that everything be done, unless a special agreement prohibits something. 2I ask, however, whether he can revoke this sanction before a debt is incurred. I think that he can do so, just as if he had given a mandate, and afterwards, having changed his mind, before the contract had been made, he had revoked the mandate and notified me. 3Also, if a father or a master has given a mandate, he is held to have conferred authority. 4And, moreover, if a master has signed the written contract of the slave, he will be liable in the proceeding aforesaid. 5But what if he becomes surety for the slave? Marcellus says that he is not liable to this action, for he intervened as a stranger; and he does not say this for the reason that the master is liable on the ground of security, but because to give authority is one thing, and to become surety is another; and he further says that even though the security may be worthless, he will not be liable on account of having given authority; and this is the more correct opinion. 6If anyone should ratify a transaction made by his slave or his son, an action on this ground will be granted against him. 7Where a ward, who is the owner, grants authority, he is undoubtedly not liable, unless he did so with the consent of his guardian. 8Where a contract is entered into with a slave by authority of the usufructuary, or with that of a person whom he is serving in good faith as a slave; Marcellus thinks that this action should be granted against him, and I also approve this opinion. 9Ad Dig. 15,4,1,9Windscheid: Lehrbuch des Pandektenrechts, 7. Aufl. 1891, Bd. I, § 73, Note 13a.Where a contract is entered into with a slave by authority of the curator of a minor, or of an insane person, or of a spendthrift; Labeo thinks that the action should be granted against the party whose slave he was, and the same applies to a veritable agent. If, however, the latter is not a genuine agent, Labeo also says that the action should preferably be granted against the party himself.

2Paulus, On the Edict, Book XXX. Where a loan is made to the slave of a ward, with the sanction of his guardian, if the loan was for the benefit of the ward, I think that an action on the ground of the guardian’s sanction should be granted against the ward. 1Where a loan is made by the authority of the master of a female slave, or by that of the father of a girl, an action on this ground should be granted against him. 2If a contract is made with a slave of another by my authority, and I afterwards purchase the slave, I will not be liable to this action; lest a proceeding which, in the beginning, was of no effect, be rendered valid by the occurrence.

3Ulpianus, Opinions, Book II. A master who has directed money to be loaned to his slave at six per cent interest, is liable for the amount which he has authorized; and an obligation of pledge does not affect lands which a slave has encumbered without the consent of his master.

4The Same, On the Edict, Book X. If any business is transacted with a slave belonging to a city, by the authority of the official appointed for the management of its affairs, Pomponius says that an action on this ground can be brought against him.

5Paulus, On Plautius, Book IV. If a master, or a father, being about to receive a loan of money, directs it to be paid to his slave or his son, there is no doubt that a personal suit for recovery can be brought against him, himself; and it is certain that, in this instance, the present action will not lie. 1Ad Dig. 15,4,5,1Windscheid: Lehrbuch des Pandektenrechts, 7. Aufl. 1891, Bd. II, § 407, Note 7.Where one of the masters of a slave directed a contract to be entered into with him, he alone will be liable; but if two directed this to be done, an action can be brought against either of them for the entire amount, because they resemble two parties who have given a mandate.