1) UNKNOWINGLY SAVING AN ANIMAL FROM HARM
QUESTION: Rav teaches that when one's animal falls into someone else's field, not only must the owner pay the value of the benefit the animal received from what it ate, but he also must pay for the benefit it received from the fruit breaking its fall. The Gemara explains that one might have thought that the owner is exempt from paying for the benefit the animal received by having its fall cushioned, because the owner of the field is considered "Mavri'ach Ari mi'Nichsei Chaveiro" -- saving his friend's property from a loss, for which the owner is not obligated to compensate him.
RASHI (DH Aval Nechbetah) explains that Rav's intention is to teach that one must pay even for the damage of the fruit that was crushed by the fall of the animal, even though the animal caused that damage unwillingly and not voluntarily.
Why does Rashi give a different explanation from that which the Gemara gives for what Rav intends to teach? The Gemara explains that Rav teaches that the principle of "Mavri'ach Ari" does not exempt the owner from liability, as Rashi himself writes in his following comment. Why does Rashi need to add another reason to exempt the owner from paying for the crushed fruit (that the damage was done through an involuntary act)? (DEVAR YAKOV)
ANSWER: RASHI seeks to answer why the Gemara suggests that the owner of the animal should be exempt because of "Mavri'ach Ari" despite the fact that the owner of the field both sustains a loss and had no intention to save the animal. (The Gemara eventually explains that the owner of the field is not considered "Mavri'ach Ari" for exactly these reasons. Rashi explains why the Gemara initially suggests that he should be considered "Mavri'ach Ari.") The Mishnah (21b) clearly teaches that when an animal jumps from the owner's roof voluntarily and breaks Kelim in the yard below, the owner must pay for the damages.
Rashi explains that the Gemara considers this an act of "Mavri'ach Ari" only because the animal did not voluntarily cause damage to the property of the owner of the field, but rather it involuntarily crushed fruit with its fall. In such a case, the Gemara considers the possibility that the owner of the field is "Mavri'ach Ari" since it is his Mitzvah to prevent a loss to his friend's animal. However, if the animal would have jumped into the field due to the negligence of the animal's owner, or if it would have jumped -- after it fell -- to a lower level of the field and the fruit on that level cushioned its fall, the owner certainly would have been obligated to pay, because the owner of the field has no obligation to lose money in order to protect someone else's animal when the animal's fall was not b'Ones but was voluntary. It is the owner's responsibility to cushion the fall of his animal when the animal jumps voluntarily (as the Mishnah states clearly on 21b).
2) AN ANIMAL THAT DAMAGES WITH ITS AMNIOTIC FLUID
QUESTIONS: Rebbi Yirmeyah asks what the Halachah would be in the case of an animal which enters another person's field and causes damage with its amniotic fluid ("Mei Leidah"). Is the owner liable because it was his negligence which allowed the animal to enter the other person's field, or is the owner exempt because he had no reason to suspect that the animal would lose its fluid? On the other hand, since the animal was due to give birth soon, perhaps the owner should have expected that such a mishap would occur.
(a) The Gemara earlier (18b) teaches that when an animal damages food by defecating on it ("Tinfah Peros b'Gelalim"), it is considered a strange way of causing damage and the owner should be liable to pay only Chatzi Nezek (unless the animal is in a tight place where it has no other choice but to release its waste there). Why, then, in the case of the animal which damages with Mei Leidah is it not considered Keren when it is an unusual way to cause damage? (M. KORNFELD)
(b) The Gemara there (18b) concludes that even when the animal is in a narrow place and its act is considered an act of Regel and not Keren, the owner still must pay only Chatzi Nezek because such an act of damage is considered Tzeroros; the animal is causing damage with something that its body releases, and not directly with its body. Why should damage caused by Mei Leidah not be considered Tzeroros to obligate the owner to pay only Chatzi Nezek? (MITZPEH EISAN)
If the Mei Leidah caused damage after the animal fell by causing someone to slip and fall, it should be considered Bor and the owner should be exempt if it damages Kelim or fruit, according to Shmuel. The RAMBAM (Hilchos Nizkei Mamon 3:11) writes that the question of Rebbi Yirmeyah refers to an animal which damages fruit with its Mei Leidah. Why, then, is the owner liable, according to Shmuel?
ANSWERS:
(a) Perhaps the damage caused by Mei Leidah indeed is considered Keren and the owner pays only Chatzi Nezek. Alternatively, one pays Nezek Shalem only if the animal has no other place to stand. However, the RAMBAM (Hilchos Nizkei Mamon 3:11) does not make either of these distinctions. He implies that one pays Nezek Shalem any time his animal damages with Mei Leidah because it is considered Regel.
Perhaps the difference between the case of Mei Leidah and the case of Tinfah Peros b'Gelalim is as follows. Although the Mishnah (2a) describes Keren as "Kavanaso l'Hazik" ("it has intention to do damage"), the Gemara in many places (such as in the case on 18b) mentions that it is not necessary for the animal to intend to do damage in order to be considered Keren. Rather, any time the animal causes damage in an unusual manner, it is considered Keren -- even if the damage is done for its own benefit (for example, when a dog eats a large sheep (15b); see Insights to 19b).
However, even though the animal does not have to intend to do damage in order to be considered Keren, the animal does need to intend to do the unusual act voluntarily. When the animal damages with Mei Leidah -- which normally does not exit the body through a voluntary act -- it can be considered only Regel but not Keren. (M. KORNFELD)
(b) The CHAZON ISH (6:2) writes that Rebbi Yirmeyah indeed only intends to obligate the owner of the animal to pay Chatzi Nezek, because Mei Leidah is considered Tzeroros. However, as mentioned above, the Rambam implies that one pays Nezek Shalem for damage caused by Mei Leidah.
The DARCHEI DAVID (cited by the DEVAR YAKOV) points out that the Rambam may follow the opinion of the RI MI'GASH (cited by the Shitah Mekubetzes on 19a). The Ri mi'Gash explains that if the animal was ill and its waste was a continuous flow that came directly from the animal to the fruit that it damaged, it is not similar to a pebble that shoots out from under the animals foot, since the waste is still touching the animal at the time that it damages the object. Therefore, if the Mei Leidah reached and damaged the fruit in a continuous flow while part of it was still touching the animal, the owner is obligated to pay Nezek Shalem, since in such a situation it is not considered Tzeroros.
Alternatively, perhaps amniotic fluid is considered like part of the animal itself, an extension of the animal's body. This certainly could be the case according to Rava (47a) who maintains that "Ubar Yerech Imo" ("a fetus is part of the mother's body"), and it could be the case even according to those who maintain that the fetus is not considered part of the mother. The fluid around the fetus and the sack which contains it -- which are not a separate, living entity -- are considered part of the mother's body.
In fact, the Gemara earlier (18b) points out that there are grounds to consider Gelalim as part of the body of the animal, and therefore damage caused by Gelalim might not be considered Tzeroros. (Damage caused by Gelalim may be compared to an animal that kicks and a piece of its hoof breaks off and causes damage. Such damage is not considered Tzeroros since the animal did not damage by means of an external object.) Although the Gemara there concludes that Gelalim is not considered part of the animal, the amniotic fluid is identified with the animal more than the Gelalim and therefore it is not considered Tzeroros. (M. KORNFELD)

58b----------------------------------------58b

3) ASSESSING THE VALUE OF DAMAGED FRUITS
OPINIONS: The Mishnah (55b) teaches that when an animal eats fruit from a person's field, the value of the damage is assessed based on the devaluation of the field. The owner is not obligated to pay simply the value of the fruit that his animal ate. The Gemara derives this from the verse, "bi'Sdeh Acher" (Shemos 22:4). The Gemara inquires about how exactly the damage is assessed. Rebbi Yosi bar Chanina explains that we assess the value of "one Se'ah from sixty Se'ah." Rebbi Yanai says that we assess the value of one half-Se'ah from sixty half-Se'ah. Chizkiyah says that we assess the value of one plant from sixty plants.
What does it mean to assess "one Se'ah out of sixty Se'ah"? The damage was not necessarily done to a Se'ah; it might have been done to more than a Se'ah or less than a Se'ah!
(a) RASHI explains that according to Rebbi Yosi bar Chanina, two assessments are made. In the first, we assess the devaluation of the Beis Se'ah in which the fruit was eaten. The owner does not have to pay for the market value of the fruit. For example, if the fruit that was eaten was worth 10 Zuz in the marketplace, its value is 5 Zuz if we assess the difference in value of the entire Beis Se'ah in which the fruit grew, since before the damage the Beis Se'ah was worth 100 Zuz, and after the damage it is worth 95 Zuz. In this example, the damage to the Beis Se'ah was five per cent of the value of the Beis Se'ah.
In the second assessment, we assess how much a single Beis Se'ah would be worth had it been sold together with another 59 Beis Se'ah, at the wholesale price. For example, instead of paying 6000 Zuz for 60 Beis Se'ah (at 100 Zuz each), a wholesaler charges only 5400 Zuz for 60 Beis Se'ah, such that each Beis Se'ah is worth 90 Zuz at the wholesale price.
We now apply the formula derived from the first assessment to a 90-Zuz Beis Se'ah and say that if five per cent of a 90-Zuz Beis Se'ah was damaged, the value of the damage would be only 4.5 Zuz. The Mazik therefore pays only 4.5 Zuz.
When Rebbi Yosi bar Chanina says "Se'ah," he refers to the first assessment, and when he says "b'Shishim Se'in," he refers to the second assessment which gives a Se'ah the wholesale price.
TOSFOS asks what Rashi's source is for assuming that two assessments are made. The verse of "bi'Sdeh Acher" implies only a single assessment. It appears that according to Rashi the verse teaches that only the second assessment is made and the wholesale value is used in order to be more lenient on the Mazik. The first assessment, according to Rebbi Yosi bar Chanina, is based on logic. Since the fruit is not yet ready to be sold on the market, its true value can be determined only as part of the whole field's value. (See Rashi to 59b, DH b'Shishim.)
(b) TOSFOS (DH Shamin) writes that whether the damage is more than a Se'ah or less, according to Rebbi Yosi bar Chanina we always evaluate the damage by assessing a sixty-Se'ah field in which one Se'ah of the field was damaged in such a manner. We then take the value of the damage and multiply it by the number of Se'in that were damaged in this particular case. Why do we not simply look at the total amount that was damaged as though it were part of a field sixty times larger? Why must we first evaluate one Se'ah of damage and then multiply it? Tosfos explains that when the damage is greater, it devaluates a field that is sixty times larger to a greater extent than when the damage is less (as Rashi mentions in DH Mipnei she'Pogem).
According to Tosfos, what is the source for evaluating the damage of a Se'ah in a field sixty times larger, rather than the entire damage that was done in a field sixty times larger? The verse teaches only to assess the damage according to the evaluation of a field sixty times greater. It does not tell us to look only at a portion of the damage.
Apparently, according to Tosfos, too, this part of the evaluation is based on logic, since such an assessment will prevent overcharging or undercharging the Mazik.
(c) The RA'AVAD cited by the RASHBA writes that even according to Chizkiyah, we evaluate the entire area of the damage by determining how much it devaluates a field sixty times larger. When Chizkiyah mentions a Se'ah, he means that if the entire damage was less than a Se'ah we do not bother to evaluate the damage by how much it causes a field sixty times larger to depreciate. Rather, we make the Mazik pay the market price for whatever was damaged (since the damage was not very large in any case and the Mazik will not have to pay a large sum).
According to the Ra'avad, Rebbi Yosi bar Chanina simply limits the Gezeiras ha'Kasuv -- which teaches to evaluate with Shishim -- to large damages.
HALACHAH: According to all three opinions, Chizkiyah says the same thing. We make a single evaluation in which we assess how much the entire area that was damaged would cause a field sixty times as large to depreciate in value.
The ROSH (6:8) writes that this is the Halachic opinion, since all the Sugyos which follow discuss merely evaluating whatever damage that was done b'Shishim without giving any additional assessments or limitations to the size of the damage.

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