6. It is theft, not only when anyone takes away a thing belonging to another, in order to appropriate it, but generally when anyone deals with the property of another contrary to the wishes of its owner. Thus, if the creditor uses the thing pledged or the depository the thing deposited, or the usuary employs the thing for another purpose than that for which it is given, it is a theft; for example, if anyone borrows plate on the pretense of intending to invite friends to supper, and then carries it away with him to a distance, or if anyone borrows a horse, as for a ride, and takes it much farther than suits such a purpose, or, as we find supposed in the writings of the ancients, takes it into battle.
7. A person, however, who borrows a thing, and applies it to a purpose other than that for which it was lent, only commits theft, if he knows that he is acting against the wishes of the owner, and that the owner, if he were informed, would not permit it; for if he really thinks the owner would permit it, he does not commit a crime; and this is a very proper distinction, for there is no theft without the intention to commit theft.
8. And even if the borrower thinks he is applying the thing borrowed contrary to the wishes of the owner, yet if the owner as a matter of fact approves of the application, there is, it is said, no theft. Whence the following question arises: Titius has urged the slave of Maevius to steal from his master certain things, and to bring them to him; the slave informs his master, who, wishing to seize Titius in the act, permits his slave to take certain things to Titius; is Titius liable to an actio furti, or to one servi corrupti, or to neither?
Titius was liable to both these actiones
This doubtful question was submitted to us, and we examined the conflicting opinions of the ancient jurists on the subject, some of whom thought Titius was liable to both these actiones, while others thought he was only liable to the actio of theft; and to prevent subtleties, we have decided that in this case both these actiones may be brought.
For, although the slave has not been corrupted, and the case does not seem therefore within the rules of the actio servi corrupti, yet the intention to corrupt the slave is indisputable, and he is therefore to be punished exactly as if the slave had been really corrupted, lest his impunity should incite others to act in the same criminal way towards a slave more easy to corrupt.
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