Clarification: 'Whether he deposited it by me', but if he would say 'I do not know whether I returned it to you', he would be Chayav according to everybody, in accordance with the Reisha of the Mishnah ...

Clarification (cont.): And it is to the Seifa that the Gemara will shortly compare it (the current case).

Halachah: We Pasken like Rav Nachman in money matters.

Halachah: Rashi explains that one nevertheless makes him swear a Shevu'as Hesses that he doesn't know ...

Reason: ... since it is no different than if he were to completely deny the claim.

Explanation #1: Evidently, Rashi holds like the first Lashon of Rav Nachman in Perek Shevu'as ha'Dayanim (Shevu'os, Daf 40b & 41a [See Tosfos there DH 'Ma'an']) ...

Explanation #1 (cont.): That Rav Nachman says 'u'Mashbi'in oso Shevu'as Hesses' in connection with the Reisha - Ein lach be'Yadi K'lum', Patur - and Rav Nachman rules 'Mashbi'in oso Shevu'as Hesses'.

Explanation #2: Others however, learn it on the Seifa - where Shimon initially admits that he has Reuven's Manah, only where he later claims that he paid him ...

Explanation #2 (cont.): And it is specifically there that Rav Nachman obligates him to make a Shevu'as Hesses, but not in the Reisha.

Proof #1 for Explanation #1: The Halachah however, is like the first Lashon, which is learned in the Gemara S'tam, whilst the second Lashon is learned by Rav Chaviva.

Proof #2 for Explanation #1: And in the first Perek of Bava Metzi'a (Daf 5a [See Tosfos DH 'Ein']) in connection with 'That shepherd', the Gemara also cites the first Lashon of Rav Nachman.

Proof for Explanation #2: But Rabeinu Tam maintains that one cannot obligate him to swear from a Safek, there where there is no 'D'rara de'Mamona' (where he did not previously admit that he owes him), seeing as there are two Leshonos.

Refutation of Proof #2: And in the first Perek of Bava Metzi'a (Ibid.) it mentions the first Lashon La'av Davka (not specifically) ...

Proof: ... bearing in mind that it is a case of 'D'rara de'Mamona', since witnesses came that he ate two of them.

Qualifying Rabeinu Tam: The Ri heard that, in fact, Rabeinu Tam allowed the Dayanim to obligate a Shevu'ah, even where there is no 'D'rara de'Mamona', only he himself did not want to rule like that.

Chidush: And where he agrees that he is Chayav only he claims that he paid, the Ri saw that Rabeinu Tam obligated him to swear ...

Implied Question: ... despite the fact that there were no witnesses regarding his admission, and he could therefore have denied it when he claimed that he had paid.

Answer: ... and he explained that it is justifiably considered 'D'rara de'Mamona', just as in the case where he claimed that he had returned it - despite the fact that he admitted there in front of two witnesses.

Refutation: Strictly speaking however, it seems that the opinion that learns it on the Seifa considers it 'D'rara de'Mamona because there are witnesses present when he admits, and that he is therefore not able to subsequently deny.

Support for Rabeinu Tam: Rav Hai Ga'on too, maintains that we only make him swear where there is no 'D'rara de'Mamona'.

Conclusion: Beis-Din do, however, place him is Cherem on condition that the Cherem will take effect in the event that he is Chayav and fails to admit it.

Implied Question: And when Rebbi Elazar said earlier in ha'Koneis (Daf 57a) that everyone needs the consent of the owner except for Hashavas Aveidah ...

Answer: ... we do not need to say that he argues with this Sugya ...

Answer (cont.): ... because what he meant was that everyone needs the consent of the owner' - provided he knows about it, 'except for Hashavas Aveidah' - which doesn't, even if he knows that he lost that article.

Clarification: S'tam purse is generally with the owner's knowledge, since one tends to check one's pockets regularly, whereas S'tam lamb is generally without his knowledge ...

Consequence: ... which explains why the Gemara mentions 'with his knowledge' by the former, and 'without his knowledge' by the latter.

Reference: It is explained in Bameh Ishah' (Shabbos, Daf 60b, DH 'Hashta'), in connection with the Sugya of 'Sandal ha'Mesumar'.