1) PAYING "KEREN" WITHOUT A "SHEVU'AH"
OPINIONS: The Gemara explains that Tana'im disagree about which is a greater Chumra -- an obligation to pay the Keren without a Shevu'ah, or an obligation to pay the Kefel with a Shevu'ah. If paying Kefel with a Shevu'ah is a greater Chumra, then a Kal va'Chomer cannot teach that a Shomer Sachar is liable for everything for which a Shomer Chinam is liable, because the laws of a Shomer Chinam are more Chamur in that he pays Kefel in a case of "To'en Ta'anas Ganav" (he claimed that the object was stolen and it turned out that he himself stole it), while a Shomer Sachar does not pay Kefel. Similarly, a Kal va'Chomer cannot teach that a Sho'el is liable for everything for which a Shomer Sachar is liable, according to the opinion that Listim Mezuyan is a Ganav, since a Shomer Sachar pays Kefel if he claims that the item was stolen by Listim Mezuyan, while a Sho'el does not pay Kefel. This shows that a Shomer Sachar is sometimes more Chamur than a Sho'el.
What is the logic of the Tana who maintains that paying Keren without a Shevu'ah is more Chamur than paying Kefel with a Shevu'ah?
(a) TOSFOS (DH Lo) explains that paying Keren without a Shevu'ah and paying Kefel with a Shevu'ah are mutually exclusive. The only way a Shomer can pay Kefel for a "Ta'anas Ganav" is when he attempts to exempt himself with that claim from paying for the object. If the Shomer is liable to pay for the object when he says that it was stolen and he is not able to exempt himself from payment through a Shevu'ah, he can never pay Kefel. Since the Shomer cannot be liable to pay both the Keren without a Shevu'ah and Kefel with a Shevu'ah, the Torah can give the Shomer that is more Chamur only one of these two Halachos. Logically, paying Keren every time the Shomer claims that the object was stolen is a greater Chumra than having to pay Kefel in the rare event that the Shomer tried to steal the object by claiming falsely that it was stolen from him. Therefore, the fact that a Sho'el can never pay Kefel does not show that it is less Chamur than a Shomer Sachar or Shomer Chinam. On the contrary, he always pays for Geneivah v'Aveidah because his laws are more Chamur and, as a result, he can never pay Kefel.
The opinion that paying Kefel with a Shevu'ah is more Chamur maintains that even though the obligation of Kefel means that the Shomer is not obligated to pay Keren as soon as he claims that the object was stolen, nevertheless it reflects a certain Chumra and can be used as a Pircha on a Kal va'Chomer.
If the Chiyuv of Kefel arises because of a false Shevu'ah, why does the Chiyuv apply only when the Shomer claims that the object was stolen by a Ganav and not when the Shomer claims that it was stolen by a Gazlan or that it was lost? (Shevuos 49a; see TOSFOS here, DH Nimtza.) Obviously, the Chiyuv of Kefel arises because the Shomer is considered to have done whatever it was that he claimed was done to the object, and the Shomer is punished more for being a Ganav of the object he was supposed to watch than for being a Gazlan of the object. This implies that the obligation of Kefel is related to the Shomer's Chiyuv Shemirah (his responsibility towards the owner of the object), and it is not merely a result of his false Shevu'ah. Why, then, does Rashi write that the Kefel is only a Kenas (penalty) for swearing falsely?
Rashi apparently means that the main cause for the Kenas is swearing falsely. The Torah's penalty was to consider the Shomer to have done whatever it was that he claimed (under oath) was done to the object. The opinion that Kefel is more Chamur than Keren without a Shevu'ah maintains that the Kefel is primarily a penalty for his breach of responsibility to the owner, and the false Shevu'ah is only a secondary cause for the Kefel.
According to this understanding, the words "b'Lo Shevu'ah" ("without a Shevu'ah") mean that the Shomer does not have the option of exempting himself through the Shevu'ah. "Kefel b'Shevu'ah" means that the Shomer does have the option to exempt himself from paying by making a Shevu'ah. (This is also the way the ASVUN D'ORAISA, Kuntrus Acharon, end of #15, explains the Gemara, as well as the RASHASH in Bava Metzia 41b and 94b.)
(b) RASHI here (DH Karna) explains the Gemara differently. Apparently, Rashi is bothered by the Gemara's usage of the word "b'Shevu'ah." According to Tosfos, the Gemara should have simply said that paying Keren immediately is more Chamur than paying Kefel if he is caught lying. There is no need to emphasize a Shevu'ah, as the Rashash asks in Bava Metzia (41b). Rashi, therefore, explains that the word "b'Shevu'ah" means that the Shevu'ah creates the obligation and "b'Lo Shevu'ah" means that the obligation is created even without a Shevu'ah. The Gemara is saying that paying Keren when the Shomer claims that it was stolen is more Chamur since the Chiyuv of Keren comes because of the obligation that the Shomer has to the one who gave him the object to watch. Kefel, on the other hand, is paid only after the Shomer swears falsely and affirms that the object is not with him. Accordingly, the obligation of Kefel is not necessarily because of the Shomer's obligation to guard the object, but rather it is a penalty for swearing falsely. Therefore, it does not reflect a Chumra in the manner of Shemirah that was done. (The opinion that maintains that Kefel with a Shevu'ah is more Chamur than Keren without a Shevu'ah indeed maintains that the obligation of Kefel does arise because of the Shomer's Chiyuv to watch the object.)
(This also seems to be the intention of Rashi in Bava Metzia 41b and 94b.)
2) "MY ANIMAL SHOULD NOT HAVE EATEN THE FRUIT"
QUESTION: The Gemara initially quotes Rav as saying that if an animal falls off a rooftop and crushes someone else's fruit, the owner of the animal must pay according to the value of the benefit that the animal derived from the fruit, but not the full value of the fruit. However, if the animal ate the fruit that it found near where it fell, the owner is completely exempt from paying.
Why should the owner be completely exempt? The Gemara answers that Rav maintains that the owner of the animal may claim, "My animal should not have eaten the fruit!"
The Gemara immediately rejects this answer and says that the owner cannot exempt himself with such a claim from paying for damages that his animal caused by eating. He can exempt himself in this manner only from damages that someone else's animal sustained by eating his fruit ("Your animal should not have eaten my fruit!").
What is the Gemara's initial assumption when it suggests that the owner of the animal may exempt himself with such a claim? If such a claim is valid, one should never be obligated to pay for damages of Shen, since one can always claim that his animal should not have eaten the food! (RE'AH cited by the Shitah Mekubetzes)
(a) The RE'AH answers that the Gemara initially assumes that one could become obligated for damages of Shen by not watching his animal and thereby allowing it to enter another person's field and eat the fruit there. However, in the case of the animal which fell off a rooftop b'Ones (beyond its, or the owner's, control) into another person's field, the owner is not responsible for allowing the animal to enter the field. Therefore, the fact that his animal eats in that field also cannot obligate him.
The Re'ah seems to understand the Gemara according to Tosfos' initial interpretation of the phrase, "it should not have eaten" (Tosfos 47b, DH Havah Lah she'Lo Tochal). Tosfos there explains that this phrase could mean that if the animal eats fruits, it is considered an Ones (like a Ru'ach she'Einah Metzuyah) since the animal is not expected to eat fruits that cause harm to its body. (Although Tosfos concludes that this is not the true meaning of the phrase, the Havah Amina of the Gemara was that this is the meaning of the phrase.)
The Gemara assumes that one does not need to guard his animal from eating other people's fruits, since it is unusual for an animal to eat fruits that it is not being fed. However, since a person can prevent his animal from wandering into another person's field, if he does not do so due to negligence he will be obligated to pay for what the animal eats there. In the case of Rav, the owner was not negligent; his animal fell into another's field b'Ones, and it also ate b'Ones.
(b) It is still difficult to understand why an animal that eats someone else's fruit is considered an Ones. Every animal needs to eat! If the food is not harmful, why should the animal be expected not to eat it? Perhaps the Gemara thought that Rav was referring only to an animal that had already been fed. Since it already ate its fill, it is considered an Ones when the animal eats more fruit. Hence, the verse that obligates a person for Shen might refer to an animal that had not eaten already. (M. KORNFELD)