MISHNAH. WE HAVE NO FEAR THAT A WEASEL MAY HAVE DRAGGED [LEAVEN] FROM ONE ROOM TO ANOTHER OR FROM ONE SPOT TO ANOTHER. FOR IF SO, [WE MUST ALSO FEAR] FROM COURT-YARD TO COURT-YARD AND FROM TOWN TO TOWN, [AND] THE MATTER IS ENDLESS. GEMARA. The reason is that we did not see it take [leaven]; but if we saw it take [it] we do fear, and it requires a [re-]search. yet why so; let us assume that it ate it? Did we not learn: The dwellings of heathens are unclean, and how long must he [the heathen] stay in a dwelling so that it should need searching? Forty days, even if he has no wife. But in every place where a weasel or a swine can enter no searching is required! — Said R. Zera, There is no difficulty: one treats of flesh, the other of bread: in the case of flesh it [the weasel] leaves nothing, [whereas in the case of bread it does leave [something] — Raba said: How compare! As for there, it is well: it is [a case of mere] ‘say’: say that there was [a burial there], say that there was not. And if you assume that there was, say that it [e.g., a weasel] ate it. But here that we see for certain that it has taken [leaven], who is to say that it ate it? Surely it is a doubt [on the one hand] and a certainty [on the other], and a doubt cannot negative a certainty. But cannot a doubt negative a certainty? Surely it was taught: If a haber dies and leaves a store-house full of produce [crops]. even if they are but one day old, they stand in the presumption of having been tithed. Now here these crops were certainly liable to tithe, and there is a doubt whether they have been tithed or not tithed, yet the doubt comes and negatives the certainty?-There it is one certainty against another certainty, as [we presume that] they have certainly been tithed, in accordance with R. Hanina of Hozae. For R. Hanina of Hozae said: There is a presumption concerning a haber that he does not let anything untithed pass out from under his hand. Alternatively: it is a doubt [on the one hand] and a doubt [on the other]; perhaps from the very beginning say that it was not liable to tithe, in accordance with R. Oshaia. For R. Oshaia said: one may practise an artifice with his produce and take it in its husks, so that his cattle may eat thereof and it be exempt from tithes. But cannot a doubt negative a certainty? Surely it was taught, R. Judah said: It once happened that the bondmaid of a certain oppressor in Rimon threw her premature-born child into a pit,ᵃᵇᶜᵈᵉᶠᵍʰⁱʲᵏˡ