Nedarim

What is [the ruling of] Hanan? — We learnt: If a man departed overseas, and another arose and supported his wife: Hanan said: He has lost his money.  But the sons of the High priests  disputed this and maintained: He must swear how much he expended and is reimbursed [by the husband]. R. Dosa b. Harkinas ruled as they did; whilst R. Johanan b. Zakkai said: Hanan has ruled well — it is as though he had placed his money upon a deer's horn. Now, Raba did not say as R. Hoshaia, because he interpreted our Mishnah to harmonize with all views. R. Hoshaia did not say as Raba: [to settle a debt] that need not be repaid is forbidden as a preventive measure on account of [a debt] that must be repaid. AND RETURN A LOST ARTICLE TO HIM. R. Ammi and R. Assi [differ thereon] — one said: This is only when the property of the finder  is forbidden to the loser, so that in returning it to him, he returns what is his own.  But if the property of the loser is forbidden to the finder, he may not return it, because he benefits him by R. Joseph's perutah.  But the other maintained: Even if the finder may not benefit from the loser's property, he may return it, and as for R. Joseph's perutah, this is rare.