Bava Metzia

[apparently] only if he [the finder] did use it. But if not, [all would agree] that if it is lost he is free [from responsibility]. Shall we say that this refutes R. Joseph? For it has been stated. A bailee of lost property: Rabbah ruled, he ranks as an unpaid bailee; R. Joseph maintained. as a paid bailee!  — R. Joseph can answer you. As for theft and loss, all agree that he is responsible. They differ only in respect to [unavoidable] accidents, for which a borrower [alone is responsible]. R. Tarfon holds: The Rabbis permitted him [the finder] to use it, therefore he is a borrower in respect thereto. Whilst R. Akiba holds that the Rabbis did not permit him to use it, therefore he is not a borrower in respect thereto. If so, why does R. Akiba say 'THEREFORE'? For if you agree that they differ concerning theft and loss, it is well; hence it is taught. R. AKIBA MAINTAINED, HE MUST NOT USE IT; THEREFORE IF IT IS LOST HE BEARS NO RESPONSIBILITY. For I might think he is a paid bailee, in accordance with R. Joseph's view, and responsible for theft and loss; hence we are informed, 'THEREFORE' [etc.] i.e., since you say that he may not use it, he is not a paid bailee, nor is he responsible for theft and loss. But if you say that all agree that he is responsible for theft and loss, whilst they differ only in respect of [unpreventable] accidents, for which a borrower [alone is responsible], what is the meaning of R. Akiba's 'THEREFORE'? Surely he [the Tanna] should have stated thus: R. AKIBA MAINTAINED, HE MUST NOT USE IT [and no more]; then I would have known myself that since he may not use it, he is not a borrower, hence not responsible. What then is the need of R. Akiba's 'THEREFORE'?  — On account of R. Tarfon's 'THEREFORE'.  And what is the purpose of R. Tarfon's 'THEREFORE'? — He means this: Since the Rabbis permitted him to use it, it is as though he had done so,  and he is [therefore] held responsible for it. But it is taught, [IF] IT IS LOST!