Implied Question: The reason he refers to the Taharos that they did, rather than to say that the man himself is Tahor is ...

Answer: Because even though the man has a Chezkas Taharah, he is still obligated to Tovel and to receive Haza'ah, in case they both touch the T'rumah, in which case it will become Vaday T'rumah Teme'ah, and whoever eats it transgresses an Asei; or in case they both touch a person who enters the Beis-ha'Mikdash, and who will be Chayav a Chatas.

Clarification: It seems that this is mi'de'Rabbanan, because min ha'Torah, they ought to be Patur, even if they ask simultaneously.

Question #1: The Ri asks how it is possible to compare this case to that of a valley, since here even if there is only one Safek, we establish the room be'Chezkas Baduk, as we explained earlier (9: DH 'Haynu').

Question #2: Moreover, whereas the Gemara there compared it to a Safek Tum'ah bi'Reshus ha'Rabim, now we are comparing to a Safek Tum'ah bi'Reshus ha'Yachid.

Clarification: The Ri establishes the Machlokes here by S'fek S'feika, as does Rabeinu Tam in the last Perek of Maseches Avodah-Zarah (Daf 70.).

Rashi: Though Rashi explains it differently.

Rebbi Eliezer's Reason: It seems to the Ri that Rebbi Eliezer is Metaher by a S'fek S'feika, because we can only learn from Sotah to be Metamei in the R'shus ha'Yachid by one Safek, similar to the case of Sotah, but not by a double Safek.

Rabbanan's Reason: Whereas, according to the Rabbanan, seeing as strictly speaking (bearing in mind that there is a Chezkas Taharah), even one Safek ought to be Tahor, yet it is Tamei, it will be Tamei even when there are two S'feikos.

Question: Even Rebbi Meir, who says that 'Once something is Tamei it has a permanent Chezkas Tum'ah ... ', the ramifications of which concern Taharos that are subsequently done there, here where he searched and did not find, what is one supposed to do? If one obligates him to search again, he will still not find?

Answer: Rashi explains that even Rebbi Meir will concede here that a mouse ate the Chametz, since Bedikas Chametz is only mi'de'Rabbanan.

Question: The Gemara however, specifically states that it is a Machlokes Rebbi Meir and the Rabbanan?

Answer: It speaks here where he did not make Bitul Chametz, and what the Gemara therefore means is that according to Rebbi Meir, the Bedikah will not suffice, seeing as he did find Chametz, in which case there is a Safek La'av of "Lo Yimatzei", and it is therefore necessary to make Bitul Chametz. And this will suffice even according to Rebbi Meir, who is speaking about a case of Safek Tum'ah d'Oraysa, whereas Bedikas Chametz is only de'Rabbanan.

Explanation #1: Rashi explains that one brings Sela'im to the value of a Manah, and declares that 'Wherever the money of Ma'aser Sheini is, it will now be transferred on to this money!'

Refutation #1: It is however, unnecessary to say this.

Explanation #2: Since he can just as well take a Shi'ur of Ma'aser money from the money in front of him, and declare that 'If this is the Ma'aser monsy, all well and good, and if not, then wherever it is, it is duly transferred on to this money!'

Refutation #2: And the Riva asks how, according to Rashi, one can possibly transfer the Ma'aser money on to Sela'im ...

Source: When we have learned in Perek ha'Zahav (Bava Metzi'a 45.) that 'One cannot transfer coins on to coins'.

Conclusion: Tosfos explained the issue there.

Clarification: Rebbi follows his own reasoning that 'It is the grave that is subsequently found is the one that was lost.

Clarification (cont.): Whereas according to the Rabbanan, he must search until he finds ten, as Rashi explains.

Explanation: And it speaks where all the loaves are tied together, similar to the Machlokes between Rebbi and the Rabbanan ...

Source: Since the Gemara in the first Perek of Beitzah (Daf 10:) specifically establishes their Machlokes by purses that are tied together. Otherwise, they both agree that 'Chulin and Ma'aser Sheini are mixed together'.

Conclusion: Because even though one cannot now attribute to mice, one can however, attribute it to small children.

Clarification: According to the Rabbanan, one is obligated to search, due to the suspicion that a mouse placed it there, and it is not the one that he placed.

Explanation #1: And the Rabbanan do not hold of the S'vara 'The one that one finds is the one that he lost', but like Raban Shimon ben Gamliel, who requires the entire field to be searched.

Explanation #2: Alternatively, they even hold like the Rabbanan, and it speaks where he doesn't know how many loaves he placed, and he is now required to search again in case he did not find all of them.

Question: Here, and in the first Perek of Chulin (Daf 15.) in the case of 'the bottle', we attribute it to a Tamei person, whereas in the first Perek of Nidah (Daf 4.) in the case of 'A loaf that is placed on a board, and a Tamei garment is lying below it', we attribute it to a Tahor person.

Answer #1: Rabeinu Tam answers with the Gemara in the first Perek of Shabbos, where it says (on Daf 15:) that 'They decreed Tum'ah on Safek Keilim that are found, but not on Safek Ochel'.

Answer #2: Alternatively, in the case of the loaf, the likelihood is that a Tahor person removed it, to prevent it from falling on to the Tamei garment and becoming Tamei.

Clarification: It speaks where the volume of crumbs match the entire loaf, which explains why it is not necessary to search ...

Implied Question: Even according to Raban Shimon ben Gamliel who rules that 'One must search the entire field'...

Answer: Here the fact he entered the room immediately after the child indicates the crumbs come from the loaf.

Implied Question: And even according to Raban Shimon ben Gamliel, who requires the entire field to be searched again ...

Answer: Here the fact that the mouse is still together with the loaf indicates that it is the same loaf.

Implied Question: And even according to Rebbi who holds 'The one that one that he finds is the one that he lost' ...

Answer: Here we suspect that it is not, because it is more likely that the first one remained in the house and this is another one that came out.

Clarification: Specifically here, where perhaps the snake will take it out or eat it ...

Clarification (cont.): But where the Chametz is there (is there to stay), we said above (Daf 4:) that a person is only too pleased to perform a Mitzvah with his money.

Explanation #1: Rashi explains in the sixth hour.

Question: But Rebbi Yehudah calls this same period 'the time of Bi'ur', so why does the Gemara change the expression.

Explanation #2: 'B'soch ha'Mo'ed' therefore means from the beginning of the seventh hour until the end of Pesach, and the obligation to search after the Mo'ed is based on the concern that one Chametz of Isur might get mixed up with Chametz of Heter, and one eats it.

Conclusion: Rashi however, did not want to explain it like this, because he explains in the Mishnah that the reason for searching for Chametz is in order not to transgress the Isur of 'Bal Yera'eh'.