Reference: This is explained in Sanhedrin (24b).

Pesak: Even though Rabanan argue with R. Yehudah, the Halachah follows R. Yehudah, like the ruling in Sanhedrin (26b). R. Avahu said, the Halachah follows R. Yehudah.

Inference: Here it connotes that one may play with dice (gamble).

Implied question: This is unlike Rami bar Chama, who explains the reason why a diceplayer is Pasul for testimony is because Asmachta (exaggerated promises that one does not intend to fulfill) does not acquire (and here, the loser thought that he would win. He did not plan to pay if the other wins, so it is considered that the winner steals...)

Answer: [He explains so] according to Rabanan, but according to R. Yehudah, who is Machshir when he learned another profession, he holds that such a case is not Asmachta.

Explanation: The reason it is not Asmachta is like Rashi explained in Sanhedrin (24b) because it is unlike the case in Bava Metzi'a (104b) "if I will leave [the field] fallow and not work it, I will pay 1000 Zuz";

There, it is b'Yado (in his ability). Therefore, he does not resolve to be Makneh, for from the beginning, when he stipulated, he stipulated without intent to give, and it is Asmachta, for he errs, and thinks that he will not come to this (a need to pay);

However, here he does not rely on anything, for he does not know whether or not he will win.

Support: It connotes like this in Sanhedrin (25a) regarding bird racers. It says "both of these needed to be taught;

Citation (25a): Had it taught [only] one who stipulates about something that depends on his own Da'as, [one might have thought that] there he says "I know about myself, that I know better", therefore it is Asmachta.

Inference: When it is b'Yado, it is Asmachta more.

Question (R. Tam): In Bava Metzi'a (73b), regarding one who gave coins to his friend to buy wine [and he was negligent and did not, Rav Ashi said that even if he promised to give his wine if he will not buy, this is only Asmachta]...

[The Gemara] asks why this is different than one who said "if I will leave [the field] fallow and not work it, I will pay highest quality land", and answers that there, it is b'Yado. Here, it is not b'Yado.

Inference: When it is not b'Yado, it is Asmachta more!

Answer #1: When it is totally b'Yado, and he does not exaggerate, like the case of "if I will leave fallow and not work, I will pay highest quality land." It is not Asmachta;

Or, when it is not b'Yado at all, and even so he resolves and is Makneh, like diceplayers and similar matters, it is not Asmachta;

However, when it is only slightly b'Yado, like the case of wine, and he was negligent and did not buy for him, even though wine was readily available to buy...

Still, since it depends on others, for if they will not want to sell to him, from whom will he buy?! Therefore, he does not resolve to be Makneh, and it is absolute Asmachta.

Answer #2 (R. Tam): Only in the case "if I will retract, Irvoni (my collateral) will be pardoned [to you]" in Bava Metzi'a (48b), and one who paid part of his loan and put the document with a third party [and said that if he does not pay within a set time, the lender may collect the entire debt], in Bava Basra (168a) and all such cases, is considered Asmachta;

He intends only to make the other rely on his words and believe him;

However, here they do so (play dice) with this intent, that this one or this one will profit.

Pesak (Ri): People who gamble b'Emanah (they promise that afterwards, the loser will pay the winner, the loser) is not obligated to pay. How could he acquire?

According to the opinion that it is Asmachta, even with a Kinyan it acquires only in an esteemed Beis Din, like is proven in Nedarim (27b);

And according to the opinion that it is not Asmachta, how can he acquire through words, without a Kinyan, because he defeats his friend?!

Explanation: They used to put all of their Peros in a barrel, like a Beraisa teaches above (80a) "we bring a barrel of wine, and of oil, and of dried figs, and of other kinds of Peros."

Implied question: Above (36b), a Mishnah teaches that if Nochri came to the east... and in the Gemara we establish it to discuss the mayor, and Rashi explained that he needs to complain to him.

Answer: Also this is a Mitzvah. He goes for the sake of people of his city and oversees matters of the Rabim.

Explanation: It is unreasonable that even for Eruvei Techumim mid'Rabanan, Ein Bereirah, like we said above (37b) "who is the Tana who holds that Ein Bereirah even for mid'Rabanan laws?"

Implied question: We are Me'arev only for a Mitzvah! (For what Mitzvah may a six year old be Me'arev?!)

Answer #1: Even so, a minor is Yotzei through his mother's Eruv, for it is impossible for her to leave him, for he clings to her (and she goes for a Mitzvah).

Answer #2: Also for a minor, there is a Mitzvah to be Mechanech him (train him in Mitzvos).

Implied question: Why didn't we answer that this is when his father is in the city, like we answer below (for R. Yanai and Reish Lakish)?

Answer: If so, R. Yanai and Reish Lakish would argue with Rav Asi, and the Halachah follows Rav Asi, for the Gemara brought [his teaching] in Kesuvos (65b).

Implied question: Why couldn't we give this answer for R. Yehoshua brei d'Rav Idi?

Answer: He does not distinguish between when his father is [in the city] and when he is not, since he did not give this answer. Also Rashi explained like this.

Explanation (Ri): Even R. Yochanan agrees here that "Katan" is literally a minor.

Explanation: This refers to his male and female slave, like we say in Gitin (77b) that a master owns the Yad (power of acquisition) of his slave.

Explanation: [Half of half] is two eggs.

Explanation (R. Tam): Pesul Geviyah (one who ate Tamei food is forbidden to eat Terumah) was an early decree. It was not among the 18 matters [that were decreed on the day that Beis Shamai outnumbered Beis Hillel], i.e. one who eats a Rishon [l'Tum'ah] or a Sheni [l'Tum'ah, he disqualifies Terumah - Shabbos 13b].

Proof #1: In Yoma (80b), we thought that it is mid'Oraisa, and we wanted to expound it from "v'Lo Tetam'u Bam v'Nitmesem Bam";

[Chachamim of the Gemara] were expert in the 18 matters, and if it were mid'Oraisa, they would be lacking one of the [18]!

Note: There were differences about how to count the 18. The Gemara (Shabbos 17b) asked "if so, according to R. Yosi there are only 17... if so, according to R. Meir there are 19!" Perhaps R. Meir holds that it is mid'Oraisa, and we need not answer that he counts Kelim and food that became Tamei through liquids like one decree. However, if so the Gemara there should have discussed this!

Proof #2: The words "Pesul Geviyah" connote that only the body is disqualified from eating Terumah. The decree "one who eats a Rishon" disqualifies what he touches.

Conclusion: Rather, surely Pesul Geviyah was decreed long before the 18 matters. They did not decree to disqualify what he touches, only that his body may not eat Terumah;

They decreed internal Tum'ah due to exterior Tum'ah. One who sees him eat Terumah after he ate Tamei food or drank Tamei liquids thinks that one may touch them (Tamei food or drink) externally to Tahor Terumah, just like they touch each other in the stomach (of one who ate one after the other).

Note: For the same reason, we should forbid eating Tamei food or drink after eating Terumah! Perhaps people realize that once Terumah was consumed, we are not concerned for it. The eater may be Metamei himself. Also, there is no logical way to decree. Until when may he not eat Tamei food? It would be very difficult to fulfill, if one who ate Terumah and became Tamei, e.g. a Kohen's wife became Nidah, may not be Metamei her food, e.g. she must eat through a Pashut Kli Etz, or others put the food in her mouth, and she cannot prepare food for herself...

They decreed only about [one who ate the volume of] two eggs. However, one egg, even though it can be Metamei others, they did not decree, for it is impossible that nothing remained between the teeth and gums, or it was somewhat digested (and shrunk) in his stomach;

Since they refrained from decreeing about k'Beitzah, they fixed the Shi'ur to be two eggs, which is half the meal of Beis ha'Menuga (if one stays in a house with Tzara'as long enough to eat four eggs, the clothes he is wearing become Tamei), and according to R. Yochanan ben Brokah, [they decreed about one who ate] one and a half eggs;

However, Tamei liquids, which do not [shrink when they] get digested, and all enters his innards, we do not require more than a Revi'is (the Shi'ur of Tum'as Mashkim).

Distinction: However, in the 18 matters, one who ate a Rishon, they decreed even about k'Beitzah, and he disqualifies Terumah through touching it, like it explains in Shabbos (14a) because sometimes one eats Tamei food (and while it is in his mouth, puts Terumah liquids in his mouth, and disqualifies them). It is not proper to elaborate here.