1) THE MINIMUM NUMBER OF "FIELDS"
QUESTION: The Gemara says that if a person borrows a hoe and tells the owner that he will use it "to hoe orchards," he is entitled to hoe as many fields as he wants.
The Gemara here seems to contradict the Gemara in Bava Basra (61b) that states that when a fieldowner says to a buyer, "I am selling fields to you," the buyer is entitled to only two fields, because the plural term "fields" denotes a minimum of two. Why, then, may the borrower of the hoe use the hoe for as many fields as he wants? He should be permitted to use it for only two fields. (TOSFOS DH Pardisi)
ANSWERS:
(a) TOSFOS here answers that there is a difference between a Sho'el (borrower) and a Loke'ach (buyer). The Gemara here refers to a person who borrows a hoe. In such a case, the Sho'el becomes "Muchzak," and Beis Din accepts his claim that the plural word "fields" that he used means many fields and not just two. The Gemara in Bava Basra, on the other hand, refers to a person who buys fields. In such a case, the seller, and not the buyer, is considered "Muchzak," and thus the seller is entitled to claim that the plural word "fields" means only two fields.
Tosfos' assumption that a Sho'el is considered the "Muchzak" seems to contradict a Sugya earlier. Rav Nachman (102b) states that the owner of a rented house, not the tenant, is the one who is "Muchzak." A borrower is similar to a renter, and the owner should therefore be the "Muchzak."
(b) TOSFOS in Bava Basra (61b, DH Ar'asa) rejects the notion that the Sho'el is considered to be "Muchzak" because of the abovementioned question. Tosfos there explains instead that when a person borrows an instrument to work on his "fields," it is normal for the owner to allow him to use it for many fields and not to limit it to the minimum number of two. In contrast, when one sells "fields," it is not generally the intent of the seller to sell all of his fields, and thus it is assumed that his intent is to sell only the minimum number of two.
How does Tosfos here reconcile his explanation -- that a Sho'el is considered "Muchzak" -- with the statement of Rav Nachman, who says that a Socher (and, similarly, a Sho'el) is not considered "Muchzak"? Tosfos differentiates between Karka and Metaltelin. Rav Nachman considers the owner "Muchzak" only with regard to land (or a house). When a movable object is borrowed, however, the Sho'el is considered "Muchzak." Tosfos explains that the difference between Karka and Metaltelin stems from how easily each one can be hidden. A person who rents Karka cannot hide the Karka, and therefore the owner is still considered "Muchzak." An item of Metaltelin, in contrast, can be concealed easily, and thus the Sho'el (or Socher) is considered "Muchzak."
2) PAYING FOR A COLLAPSED HOUSE
OPINIONS: The Gemara states that when a person rents a specific house ("Bayis Zeh") from a homeowner and the house collapses before the end of the rental period, the owner does not have to provide the tenant with another house. Must the tenant pay the rental fee in such a case?
(a) The RITVA in the name of the RE'AH maintains that a rental agreement is tantamount to a sale. If a house collapses after it is sold, the buyer suffers the loss and he still must pay for the house (if he has not paid for it already). Similarly, the tenant must pay the rental fee, since the house collapsed while it was in his possession. The HAGAHOS ASHIRI (6:10) writes that this is also the view of RASHI, as he infers from the words of Rashi (DH Azda) who says that "it is the Mazal of the Socher that caused [the loss]."
(b) The RAMBAN argues and maintains that the tenant is not obligated to pay for more than the actual use that he obtained from the house (that is, he pays only for the number of days that he used the house until it collapsed). (This is also the view of the RAN and ROSH.)
RAV ELCHANAN WASSERMAN Hy'd (Kovetz He'oros 53:3) explains that the Machlokes between the Ritva and the Ramban revolves around a basic dispute about how to view the nature of a rental agreement. The Ritva views a rental agreement (Sechirus) as an acquisition of the rented object (in this case, a house) for the sake of its use ("Dekel l'Perosav"). Thus, even if the renter is not able to make use of the object, he still is obligated to pay for his acquisition of the object. The Ramban, on the other hand, views Sechirus as a payment for the use of the object, and not for the object itself. The use of an object is a type of "Peros" which the object yields. Thus, the Socher is obligated to pay only for the "Peros," or use, which he actually receives from the object.
Rav Elchanan Wasserman (ibid. 53:6) points out a slight contradiction in the opinion of the Ramban. The Ramban in Kesuvos (59a) states that a person who rents a field is considered to have partial ownership of the field, and he therefore can consecrate (Makdish) his share of the field. The Ramban there even refers to the Socher's ownership as a "Kinyan ha'Guf l'Peros," which seems to be exactly the way the Ritva refers to Sechirus. Thus, the Ramban there seems to contradict his own words here, where he says that Sechirus is merely a right to use the object. Rav Elchanan Wasserman leaves this question unanswered.
The CHAZON ISH (Bava Kama 23:10) writes that the Ramban in fact may agree with the Ritva that Sechirus is a temporary sale, as he explains in Kesuvos. However, the Ramban still may understand that the Socher does not have to pay for the rest of the rental after the house collapses. This is because the agreement was that he would pay for the house only as long as it stands.

103b----------------------------------------103b

3) FOLLOWING THE LOCAL CUSTOM
QUESTION: The Beraisa states that in a place where the prevalent custom is to cut the produce from a field, a sharecropper is not permitted to uproot it. In a place where the custom is to uproot the produce, a sharecropper may not cut it. The Beraisa adds that neither the fieldowner nor the sharecropper may deviate from the local custom without the other's consent.
The Gemara goes on to explain why neither may deviate from the local custom. Since either of them may have a reason to prefer that the produce be cut in a particular way, the local custom must be followed. If the custom is to cut the produce and the sharecropper wants to uproot it, the owner can argue that he wants the roots to remain in the field in order to fertilize the soil. If the owner wants the produce to be uprooted, the sharecropper can say that he does not want to toil so much.
Similarly, if the custom is to uproot the produce and the sharecropper wants to cut it, the owner can say that he wants the land to be clean of roots. If the owner wants the produce to be cut, the sharecropper can say that he needs the roots as feed for his animals. Hence, neither may deviate from the local custom.
Why does the Gemara need to give reasons to explain why neither party may deviate from the local custom? The mere fact that it is the local custom should be reason enough to prevent either party from deviating without the other's consent. (The Gemara in many other places cites the rule, "ha'Kol k'Minhag ha'Medinah.") (NIMUKEI YOSEF)
ANSWERS:
(a) The TOSFOS YOM TOV answers that one party may force the other to follow the prevalent custom only when that custom has a logical reason. A person cannot be forced to follow a custom that has no reason, for such a custom is no better than a "Minhag Sedom." Accordingly, the Gemara here needs to explain the logical basis for the custom in order to explain why each party may force the other to abide by the local Minhag. Similarly, the SHITAH MEKUBETZES writes that in a place where the local custom has no basis, one side may force the other to deviate from the custom because of "Zeh Neheneh v'Zeh Lo Chaser."
(b) The ARUCH HA'SHULCHAN (CM 320:5), as cited by the DEVAR YAKOV, answers that the Gemara here explains why each side may force the other to follow the Minhag because there is a practical ramification from one of the reasons that the Gemara gives. The Gemara explains that in a place where the custom is to cut, and not uproot, the produce, the owner may force the sharecropper to follow the custom so that his land will be fertilized. This reason applies only when the field was rented for one year and will return to the owner's possession after these crops are harvested. When the field is rented out for two or more years -- and thus the sharecropper will be the one who has to plant the field the following year -- the owner may not force the sharecropper to follow the Minhag, and the sharecropper may choose to uproot, and not cut, the produce.
4) ROOTS FOR ANIMAL FEED
QUESTION: The Beraisa states that in a place where the prevalent custom is to cut the produce from a field, a sharecropper is not permitted to uproot it, and in a place where the custom is to uproot the produce, a sharecropper may not cut it. The Beraisa adds that neither the fieldowner nor the sharecropper may deviate from the local custom without the other's consent.
The Gemara goes on to explain why neither may deviate from the local custom. Since either of them may have a reason to prefer that the produce be cut in a particular way, the local custom must be followed. If the custom is to cut the produce and the sharecropper wants to uproot it, the owner can argue that he wants the roots to remain in the field in order to fertilize the soil. If the owner wants the produce to be uprooted, the sharecropper can say that he does not want to toil so much.
Similarly, if the custom is to uproot the produce and the sharecropper wants to cut it, the owner can say that he wants the land to be clean of roots. If the owner wants the produce to be cut, the sharecropper can say that he needs the roots as feed for his animals. Hence, neither may deviate from the local custom.
Why does the Gemara not give the same reason for the owner that it gives for the sharecropper? That is, the Gemara says that if the custom is to uproot the produce and the owner wants it to be cut, the sharecropper can refuse on the grounds that he needs the roots as feed for his animals. The same claim can be made by the owner when the sharecropper wants to cut it and not uproot it. The owner receives a portion of whatever the sharecropper harvests, including the roots, and he should also be able to argue that he wants the roots so that they can be used as feed for his own animals. Why does the Gemara give a different reason for the owner's refusal? (Acharonim)
ANSWERS:
(a) The MAHARSHA answers that the Gemara indeed could have used this reason to explain why the owner can force the sharecropper to follow the local custom. However, the Gemara gives a better reason, one which applies regardless of whether the owner has animals or wants the roots as feed for them.
(b) The RITVA, TORAS CHAIM, and RASHASH answer that the Gemara here refers to all cases of sharecropping -- whether it is a case of "Arisus" (in which the sharecropper gives a percentage of the field's produce to the owner) or a case of "Chakirus" (in which the sharecropper gives a lump sum per year to the owner, regardless of how much the field produces). Since, in a case of "Chakirus," the owner of the field does not receive what grows in the field, he cannot claim that he wants the produce to be uprooted so that he can feed the roots to his animals, since he will not receive the roots.
(c) The TORAS CHAIM answers further that this would not be a valid argument for the owner, because even if the sharecropper cuts the produce and leaves the roots in the ground, the owner still will be in possession of the roots and will be able to let his animals eat them from the ground. The sharecropper, on the other hand, may claim that he wants to uproot the produce in order to feed the roots to his animals, because he is not permitted to bring his animals into the owner's field after the conclusion of his rental period.
(d) The DARCHEI DAVID, cited by the DEVAR YAKOV, answers that if the owner claims that he wants the produce to be uprooted so that he will be able to feed the roots to his animals, the sharecropper can respond that he will uproot only half of the field's produce in order to give the owner his share of the roots. However, he may not cut the other half of the produce and leave the roots in the ground. Therefore, the Gemara says that the owner may force the sharecropper to uproot all of the produce because he wants his field to be clean.