Question (Ravina): Did R. Yochanan really say that this (that the Halachah follows R. Shimon, and it is permitted whether or not they are Me'arev)?!

R. Yochanan said that the Halachah follows a Stam Mishnah!

(Mishnah): If a wall between two Chatzeros is 10 Tefachim tall and four Tefachim thick, the Chatzeros can be Me'arev individually, but not together;

If there are fruits on top of the wall, people from either Chatzer may alight on the wall and eat them, but they may not take them down.

Answer (Rav Ashi): It means that they may not take them down to the house [but they may take them down to the Chatzer].

Question (Ravina): R. Chiya taught a Beraisa saying '...as long as each does not stand in his place and eat'.

Answer (Rav Ashi): If Rebbi did not teach this [explicitly], how did R. Chiya (his Talmid) know this?! (R. Chananel - Rebbi must have known that the Beraisa is unreliable.)

(Rav Huna): If there is a ruin between two Chatzeros, and only one of the Chatzeros was Me'arev, the Chatzer that was not Me'arev gets [a Heter to transfer to and from] it;

Version #1 (Chiya bar Rav): [Rav said that] it is even [accessible] to the one that was Me'arev, i.e. [therefore] both are forbidden;

You cannot say that he permits both. If so, he should also allow a Chatzer that was Me'arev to transfer to a Chatzer that was not Me'arev! (The law is the same when both were Me'arev, and Rav said that R. Shimon forbids in this case. We discuss when one was not Me'arev for this is more similar to the case of the ruin.)

Rejection: Perhaps he forbids transferring only between Chatzeros, because Kelim are guarded there. (Many house Kelim are taken to the Chatzer and found there.) People might [mistakenly] transfer [Kelim that were Shoves in the house to the other Chatzer, which is forbidden].

He permits regarding a ruin. Since Kelim are not guarded there we are not concerned lest people transfer [what is forbidden].

Version #2 (Chiya bar Rav): [Rav said that] it is even to the one that was Me'arev, i.e. both are permitted;

Question: Perhaps he forbids both, just like he forbids a Chatzer that was Me'arev to transfer to one that was not!

Answer: No, he forbids regarding Chatzeros because Kelim are guarded there, so people might transfer [to the other Chatzer].

Kelim are not guarded in a ruin. We are not concerned lest people transfer.

(Mishnah): If a wide roof is next to a narrow roof, the wide roof is permitted, and the narrow roof is forbidden. (We always discuss when they were not Me'arev together);

If a wide Chatzer was breached to a narrow Chatzer, the wide Chatzer is permitted, and the narrow Chatzer is forbidden, for it is like an opening of the wide one [but not vice-versa].

(Gemara) Question: Why does the Mishnah teach both of these (roofs and Chatzeros)?

Answer #1: According to Rav, it teaches about a roof that resembles a Chatzer. Just like the walls of a Chatzer are visible, the walls of a roof must be Nikarim [for it to be permitted].

Answer #2: According to Shmuel, it teaches about a roof that resembles a Chatzer. Just like Rabim traverse a Chatzer, Rabim traverse the roof. (If not, also the narrow roof is permitted, for we apply Gud Asik to the wall between the houses even though it is not Nikar.)

(Rabah, R. Zeira and Rabah bar Rav Chanan): Our Mishnah teaches that the residents of the wide [enclosure dominate and] are 'in' the narrow one [the entire narrow enclosure is called the opening of the wide one], but not vice-versa.

Application #1: If there are vines in the wide one, one may not plant [any other crop] in the narrow one. If he did, the crop is forbidden [due to Kil'ai ha'Kerem, as if vines grow next to them without a Mechitzah between]. The vines are permitted. (From their perspective, there is a Mechitzah between them and the crop);

If there are vines in the narrow one, one may plant in the wide one [as if there were a Mechitzah in between].

Application #2: If Leah is in the wide [enclosure], and her husband threw the Get to the narrow one, she is divorced. (It is as if the Get was thrown to where she stands. Rashi - this is like the opinion that her Reshus can receive the Get for her only if she is standing in it. Tosfos - both enclosures belong to her husband. The case is, he lent to her the Reshus she is in, in order to receive the Get);

If she is in the narrow one, and her husband threw the Get to the wide one, she is not divorced.

Application #3: If the Tzibur is in the wide [enclosure], and the Shali'ach Tzibur is in the narrow one, they are Yotzei (fulfill their obligation to pray through listening to him. It is as if he is with them);

If the Tzibur is in the narrow one, and the Shali'ach Tzibur is in the wide one, they are not Yoztei (the majority is not drawn after the minority).

Application #4: If nine people are in the wide one, and one person is in the narrow one, they join [to form a Minyan];

If nine are in the narrow one, and one is in the wide one, they do not join.

Application #5: If there is excrement in the wide one, one may not read Kri'as Shma [or pray or learn Torah] in the narrow one (it is as if he is in the same Reshus as the excrement);

If the excrement is in the narrow one, one may read Shma in the wide one. (The Gefufim (walls to the side of the opening) are a Mechitzah between him and it.)

Question (Abaye): If so, [regarding Kil'ayim] the Mechitzah causes a stringency!

If not for the Mechitzah, one could distance four Amos [from the vines] and plant [anything else]. Now that there is a Mechitzah, it is forbidden [to plant in the narrow enclosure]!

Answer #1 (R. Zeira): We find that Mechitzos cause stringencies!

(Mishnah): If a wide Chatzer was breached to a narrow Chatzer, the wide Chatzer is permitted, and the narrow Chatzer is forbidden, for it is like an opening of the wide one.

If one would extend the Gefufim until both Chatzeros were the same width (see the diagram in Rashi), even the wide Chatzer would be [totally breached and] forbidden!

Rejection (Abaye): There, extending the Gefufim forbids because this [Halachically] removes the Mechitzos. (This is no source to say that erection of Mechitzos forbids regarding Kil'ayim.)