is not in accordance with the opinion of Rabbi Dosa. As it is taught in a baraita: Rabbi Dosa says, and some say Abba Shaul says: One who purchases an animal from another on the eve of a Festival, even if he did not deliver it to him until the Festival itself, it is as the feet of the purchaser. And one who delivers his animal to a shepherd, even if he did not deliver it to him until the Festival itself, it is as the feet of the shepherd. The mishna, on the other hand, teaches that an animal delivered to a shepherd remains as the feet of the owner, therefore apparently contradicting Rabbi Dosa.

The Gemara rejects the assertion that this is a contradiction. You can even say that the mishna is in accordance with Rabbi Dosa, and it is not difficult. Here, in the baraita, it is referring to a town that has only one shepherd. In that case the owner knows with certainty beforehand that he will be delivering his animal to this shepherd over the course of the Festival, and therefore the animal’s place of rest is established as being identical to that of the shepherd. There, however, the mishna is referring to a town where there are two shepherds. Since the issue of which of them will receive this animal is undetermined when the Festival begins, the animal remains as the feet of its owner. The Gemara strengthens this assertion that the mishna is dealing with a case where there are two shepherds: The language of the mishna is also precise in accordance with this interpretation, as it teaches: To his son or to a shepherd, suggesting that initially he did not know to whom he would give the animal. The Gemara concludes: Indeed, learn from this that this is so.

Rabba bar bar Ḥana said that Rabbi Yoḥanan said: The halakha is in accordance with the opinion of Rabbi Dosa, that animals given to a shepherd are as the feet of the shepherd. The Gemara asks: And did Rabbi Yoḥanan actually say this? But didn’t Rabbi Yoḥanan say a general principle that the halakha always follows an unattributed statement in a mishna? And we learned in the mishna: Animals and vessels are as the feet of the owner. One who delivers his animal to his son or to a shepherd, it is as the feet of the owner.

The Gemara answers: And did we not establish that the baraita of Rabbi Dosa is dealing with a different case than the mishna, that here in the baraita it is dealing with a town with one shepherd, whereas there in the mishna it is dealing with a town with two shepherds? There is consequently no contradiction between establishing the halakha both in accordance with Rabbi Dosa and in accordance with the mishna.

§ The Sages taught: In the case of two people who borrowed one robe in partnership from a third party, this person in order to go to the study hall with it in the morning and that person in order to enter a wedding feast with it in the evening, and this one made a joining of Shabbat boundaries [eiruv teḥumin] for himself to the north in order to reach his destination, and that one made an eiruv for himself to the south in order to reach his destination, the one who made an eiruv for himself to the north may walk with the robe only to the north as far as it is permitted for the feet of the one who made an eiruv for himself to the south, i.e., he may go north only as far as the other borrower may go.

And similarly, the one who made an eiruv for himself to the south may walk with the robe to the south only as far as is permitted for the feet of the one who made an eiruv for himself to the north, as the robe is as the feet of both borrowers and may go only as far as both of them may walk. If each of them placed his eiruv at a distance of one thousand cubits from their house, to the north and south respectively, they may each walk, without the robe, three thousand cubits from their regular dwelling-place, one partner toward the north and the other partner toward the south. The three thousand cubits are comprised of the thousand cubits from the house to the eiruv plus another two thousand, the standard Shabbat limit, from the location of the eiruv. The one whose eiruv is in the north may not wear the robe farther than one thousand cubits north of his house, as he would then be going beyond the farthest extent of the other’s Shabbat limit, and vice versa for the one whose eiruv is in the south.

And if they made their respective limits end in the center, i.e., if one placed his eiruv two thousand cubits from the house to the south, so that the house is his farthest limit to the north, and the other placed his eiruv two thousand cubits to the north of the house, the house being his farthest limit to the south, then each of them may not move the robe from its place at all.

The Gemara records a dispute between amora’im. It was said: In the case of two people who purchased a barrel of wine or an animal in partnership before a Festival, in order to divide the contents of the barrel or the meat of the animal between them on the Festival itself, what is the halakha if the two people have different Shabbat limits? Rav said: The barrel is permitted to each of them, and each may take his portion on the Festival and transfer it within his respective Shabbat limit, which is also applicable to Festivals; but the animal is prohibited, and each portion of it may be transferred only within the limits that are shared by both purchasers. And Shmuel said: The barrel is also prohibited to be transferred beyond the limits shared by both people.

The Gemara questions the opinion of Rav, who distinguished between the case of the barrel and that of the animal. What does Rav hold? If he holds that there is retroactive designation, so that after the division of the barrel it becomes clarified retroactively which portion belonged to which partner, and the Festival place of rest for each portion is established at the start of the Festival in accordance with the person who will later become its owner, then even the animal should be permitted. And if he holds that there is no retroactive designation, so that at the start of the Festival both portions of the animal belong jointly to both of them and may therefore be transferred only within the limits shared by both people, then even the barrel should be prohibited.

The Gemara answers: Actually, the explanation for Rav is that he holds there is retroactive designation, and the reason Rav was stringent in the case of the animal is that an animal is different, as the limits absorb from each other. A live animal cannot be divided into two parts for ownership; each part of its body depends on and is nourished by the other. Consequently, even if the designation of the respective portions takes place retroactively, each portion continues to draw from the other part, so that at the time of division the two portions are once again mixed together. Rav Kahana and Rav Asi said to Rav: If that is your rationale, this indicates that the Sages were not concerned about the prohibition of muktze, as it is not assumed that each of them removed the portion of his partner from his mind, thereby prohibiting it from his own use, and yet they were concerned about the prohibition of Shabbat limits. Isn’t this illogical? Rav was silent and offered no response.

The Gemara asks: What conclusion was reached about this issue? Rabbi Hoshaya said: In general, there is retroactive designation, and they can therefore each transport their portions of both the barrel and the animal to their respective places. And Rabbi Yoḥanan said: There is no retroactive designation, and therefore they may not move their portions of either the barrel or the animal except within the limits shared by both of them.

The Gemara asks: And does Rabbi Hoshaya really hold there is retroactive designation? But didn’t we learn in a mishna: If there is a corpse in a house that has many entrances, all the entrances are ritually impure, i.e., everything situated in the space of the entrance becomes impure, even in the part that lies beyond a closed door, separating it from the corpse. Since any of the entrances might be used to remove the corpse, and none are designated for that purpose, all are rendered impure. However, if one of them was subsequently opened, then the space of that particular entrance is impure, while all the others are pure, as it is assumed that that the corpse will be removed by way of the open door. Even if none of the entrances was actually open, if one merely intended to remove the corpse through a particular one of the entrances or through a window that is at least four by four handbreadths in size, this intention of his saves all the other entrances from impurity.

The details of this last halakha are disputed by tanna’im. Beit Shammai say: And this applies only if he had this intention before the dead person died, so that at the time of death it was known which entrance would be used. And Beit Hillel say: It applies even if he had this intention only after the dead person died.

And it is stated with regard to this mishna: Rabbi Hoshaya said: When Beit Hillel said that the other entrances are pure even if one thought of removing the corpse via a particular entrance only after the person died, they meant only to purify the entrances from that point and onward; from the moment of his intention there is no more impurity in the other entrances. From this the Gemara infers: From here and onward: Yes, the other entrances are saved from impurity, but retroactively: No. Whatever was in the doorways before this intent was formulated has already contracted ritual impurity and this cannot be reversed retroactively by one’s subsequent thoughts. This indicates that the principle of retroactive designation is not accepted by Rabbi Hoshaya.

The Gemara resolves this contradiction in the following manner: Reverse the presentation of their opinions given above, and say: Rabbi Hoshaya said: There is no retroactive designation, and Rabbi Yoḥanan said: There is retroactive designation.

The Gemara questions this resolution: And does Rabbi Yoḥanan really accept the principle of retroactive designation? But didn’t Rav Asi say that Rabbi Yoḥanan said: Brothers who divided property received as an inheritance are considered purchasers from each other, and as purchasers of land they must return the portions to each other in the Jubilee year, at which point they may redistribute the property? This demonstrates that Rabbi Yoḥanan does not hold that it is retroactively established that each brother’s portion was designated for him directly upon their father’s death, but rather it is considered that all the land was joint property until the brothers traded or bought their respective portions from each other.

And if you should say: When does Rabbi Yoḥanan not accept the principle of retroactive designation? Only in regard to matters that are Torah law, but he does hold of retroactive designation in regard to matters of rabbinic law, such as the halakhot of Shabbat limits; this would account for the discrepancy.

But does he accept retroactive designation in matters of rabbinic law? Didn’t the Sage Ayo teach otherwise in regard to the halakhot of joining of Shabbat boundaries [eiruv teḥumin]? As it was taught in a mishna: One who has heard that a rabbi will be coming to a place near his town to deliver a lesson on Shabbat, but is unsure where the lecture will take place, may place two eiruvin on Shabbat eve in two different directions, while stipulating that only the eiruv on the side where the rabbi will teach will take effect. Furthermore, if he hears that two rabbis will be coming to two different locations, he may place two eiruvin and stipulate that he will decide on Shabbat which rabbi he prefers, and consequently which of the two eiruvin will take effect.

Ayo taught in a baraita that Rabbi Yehuda disagreed with this halakha and said: A person may not make a stipulation with regard to two contradictory things at once, and therefore if two Sages will be arriving, his condition is of no effect. Rather, it is true that in the first case, where he knows that a rabbi is coming but does not know from which direction, he may place two eiruvin and stipulate that if the rabbi comes from the east his eiruv in the east will take effect, and if the rabbi comes from the west, his eiruv in the west will take effect. However, in the second case, when two rabbis come to the two locations, one of them arriving here and the other arriving there, and one wants to place two eiruvin and decide on Shabbat which of the two lectures he will attend, this he may not do; that would require the identity of the functional eiruv to be determined retroactively, and one’s place of rest must be determined when Shabbat begins.