PAST DEDICATION
BAVA KAMA 17 (18 Teves) - Two weeks of study material have been dedicated by Mrs. Estanne Abraham Fawer to honor the ninth Yahrzeit of her father, Rav Mordechai ben Eliezer Zvi (Rabbi Morton Weiner) Z'L. May the merit of supporting and advancing Dafyomi study -- which was so important to him -- during the weeks of his Yahrzeit serve as an Iluy for his Neshamah.

1) "TZEROROS"
QUESTION: The Mishnah describes the Mazik of Regel. It teaches that if the animal kicks pebbles, or steps on pebbles and causes them to fly through the air, and they damage something, the owner of the animal pays only Chatzi Nezek. This is the Halachah of "Tzeroros."
RASHI explains that one pays only Chatzi Nezek for damage caused by Tzeroros because of the Halachah l'Moshe mi'Sinai. However, the reason one pays Chatzi Nezek when the animal kicks and thereby causes damage is that it is a strange way for the animal to act, and therefore it is considered Keren, as the Mishnah says (15b), and for damage caused by Keren one pays Chatzi Nezek (when it is a Tam).
If "Meva'etes," kicking, is considered Keren as the Mishnah (15b) says, why does the Mishnah here mention it altogether? The Halachah of Meva'etes has already been taught in the previous Mishnah! Moreover, since Meva'etes is Keren, it has nothing to do with Regel, which is the subject of the Mishnah here. Why, then, is it mentioned? (TOSFOS DH Meva'etes)
ANSWERS:
(a) TOSFOS explains that the Mishnah lists Meva'etes simply because it is similar to Tzeroros both in the amount that is paid and in the manner in which the damage is done. In truth, however, it does not belong in the Mishnah of Regel. It is included in this Mishnah only because of its similarity to Tzeroros.
The MAHARAM SHIF questions Tosfos' answer from the Gemara (16b) which proves from the Beraisa (19b) that the damage done by one's wild animal which kills another animal and eats it immediately ("Toref v'Ochel") is called Shen and not Keren. If it would be Keren (such that if the animal does it three times, the owner must pay Nezek Shalem because it is a Mu'ad), it would not belong in the Beraisa which discusses the Mu'ad of Shen. According to Tosfos, the Beraisa may have included it because of its similarity to Shen, even though the owner is actually liable because of Keren!
The answer to this question might be that there is no point in listing forms of damage which are similar to Shen but which pay Nezek Shalem, since most Mazikim pay Nezek Shalem. It is only the Mishnah -- which lists a Mazik which oddly pays only Chatzi Nezek -- which mentions, as an aside, the Halachah of Meva'etes which is damage caused by the foot and which also pays Chatzi Nezek.
Alternatively, Tosfos may intend to explain like the TALMIDEI RABEINU PERETZ in the Shitah Mekubetzes, who write that the Mishnah includes the Halachah of Meva'etes paying Chatzi Nezek in order to record a "Stam" Mishnah in accordance with the view of the Rabanan who argue with Rebbi Tarfon, and who maintain that Keren in Reshus ha'Nizak pays Chatzi Nezek. (The Mishnah is discussing Reshus ha'Nizak since it discusses a place where one is liable for Regel.) The Talmidei Rabeinu Peretz explain that the reason why the Mishnah gives an example of Meva'etes to teach the Halachah of the Rabanan who argue with Rebbi Tarfon, and it does not give the ordinary case of Keren -- and the reason why it includes this case in this Mishnah rather than in any other Mishnah -- is because of its similarity to the case of Tzeroros. Accordingly, the Mishnah only lists something similar to another Halachah in the Mishnah if it is able to teach something new by doing so (which cannot be said about the Beraisa on 19b).
(b) The RASHBA (see also PNEI YEHOSHUA) explains that the Gemara later (19a) presents a question whether Tzeroros of Keren pays Chatzi Nezek or half of Chatzi Nezek (i.e. a quarter of the Nezek done). The Rashba suggests that the case of Meva'etes of the Mishnah is also a case in which the animal kicked up Tzeroros in an unusual way, making it Tzeroros of Keren, and the Mishnah is teaching how much one must pay for Tzeroros of Keren -- half or a quarter of the Nezek. The reason the Gemara remains inconclusive on this matter is that the ruling of the Mishnah may be understood in one of two ways: either it is teaching that Meva'etes pays half of the entire Nezek as opposed to a quarter of the Nezek, or it is teaching that Tzeroros pays Chatzi Nezek only if it is not done through kicking (but is done in the normal manner of walking). If the kicking itself causes Tzeroros, the owner pays a quarter of the Nezek.
(c) The RASHASH suggests that the Mishnah is teaching simply what the Gemara says at the beginning of the Masechta (2b), that although kicking is done with the foot it is not called a Toldah of Regel, but rather it pays Chatzi Nezek like a Toldah of Keren. He cites proof for this from the Mishnah later (19b) which lists the cases of Shen and adds that if the animal eats clothing or something else that it does not usually eat, it pays only Chatzi Nezek. The Mishnah makes that point in order to show that not every act that involves eating is called Shen; if it is unusual, it is called Keren. The Mishnah here, also, is teaching that not everything done with the foot is called Regel.
Tosfos does not accept this answer for one of two reasons. The first reason is that this approach does not answer the first question, why the Mishnah points out that kicking is Keren when the earlier Mishnah (15b) has already taught that. The second reason is that according to the Rashash, the Mishnah should not have grouped Meva'etes together with Tzeroros. It should have said that if the animal damages by kicking, the owner pays Chatzi Nezek, and if it damages by Tzeroros, the owner also pays Chatzi Nezek. The fact that the Mishnah combines them into one Halachah ("if the animal damages by kicking or by Tzeroros, one must pay Chatzi Nezek") shows that Meva'etes is in some way related to Tzeroros.

17b----------------------------------------17b

2) "BASAR ME'IKARA AZLINAN"
QUESTION: Rava asks what the Halachah is when an animal steps on a utensil, causing it to roll somewhere else and to strike a different object and break. Is this considered Tzeroros, since the utensil that rolled broke only after it finished rolling, when it was no longer near the foot of the animal, or is this considered a normal case of Regel, since it was the kick that the animal gave it which caused it to break? The Gemara phrases the question in terms of whether "Basar me'Ikara Azlinan" -- is the damage considered to have been done at the beginning, at the moment the animal kicked the utensil (and therefore it is not a case of Tzeroros), or "Basar Tevar Mana Azlinan" -- is the damage considered to have been done at the point in time at which the utensil broke, at which time it was no longer near the animal's foot?
How can the Gemara suggest that "Basar me'Ikara Azlinan" and the damage is considered to have been done at the moment the animal kicked the utensil? According to this logic, there will never be a case of Tzeroros! Every time an animal kicks a stone that eventually hits a utensil and breaks it, the principle of "Basar me'Ikara Azlinan" should dictate that the moment the animal kicked the stone was the moment of the damage, and therefore it is not Tzeroros. When will there ever be a case of Tzeroros if "Basar me'Ikara Azlinan"?
ANSWERS:
(a) TOSFOS (DH Zarak Kli) explains that there is a difference between an animal that kicks an object which then damages another item, and an animal that kicks something which itself becomes damaged after rolling. "Basar me'Ikara Azlinan" applies only when the object which will be damaged itself has already been set into motion, and something has already been done to it (the animal has kicked it). Since it is already moving, the object itself is already considered to be broken. In contrast, the fact that an animal kicks one object cannot make a second object -- which is still motionless and nothing has been done to it at all -- be considered broken at the moment that the animal kicks a pebble towards it. Since nothing at all has begun to happen to that object yet, it cannot be considered broken until it actually breaks. (All of the Rishonim here distinguish between the two cases in a similar manner.)
Therefore, in a normal case of Tzeroros, "Basar me'Ikara Azlinan" does not apply: the damage is not considered to have been done by the animal itself, but rather by the Ko'ach of the animal, something the animal kicked or pushed which damaged a second object. In the case of Rava's question, the animal kicked a utensil which itself became damaged, and thus "Basar me'Ikara Azlinan" applies. In that case, it is the animal itself, and not the Ko'ach of the animal, that caused the damage.
(b) The KETZOS HA'CHOSHEN (CM 390:1) disagrees with Tosfos. He suggests that even if the principle of "Basar me'Ikara Azlinan" applies to something which does not break itself but which causes something else to break, there is still a distinction between an animal that kicks a utensil which breaks and an animal that kicks a rock which then breaks a utensil. He explains that even if "Basar me'Ikara Azlinan" applies, and thus when an animal kicks a rock it is as if the utensil that the rock will hit is already broken, nevertheless the utensil has been broken by the rock that hit it and not by the animal's foot itself. Accordingly, it is only the Ko'ach of the animal that does the damage, and the Halachah l'Moshe mi'Sinai teaches that something that breaks because of the Ko'ach of the animal -- because of something that the animal sets in motion -- obligates the owner of the animal to pay only Chatzi Nezek because of Tzeroros. However, when the animal kicked the utensil itself, it is the foot of the animal that broke the object and not the animal's Ko'ach, and thus "Basar me'Ikara Azlinan" states that the moment at which the foot hit the object it broke it.
The KEHILOS YAKOV (Bava Kama 4:6) explains this further by saying that the Ketzos ha'Choshen is differentiating between when the animal itself touched the object that broke, in which case it is considered damaged caused by "Gufo," the body of the animal itself, and when the animal never touched the object that broke, but rather something else which the animal kicked touched the object, in which case it is considered "Kocho" or Tzeroros, and not "Gufo."
The difference between the approach of Tosfos and the approach of the Ketzos ha'Choshen is a case in which a person throws an object, or shoots an arrow, at a utensil, and another person breaks the utensil before the arrow hits it. According to Tosfos, in such a case the person who actually broke the utensil is liable; "Basar me'Ikara Azlinan" does not apply since nothing was done to the utensil itself until the arrow hit it. "Basar me'Ikara Azlinan" applies only when the object itself was set into motion already, and that same object is the one that will break. In this case, at the time the arrow was shot, nothing happened to the utensil which eventually broke. Therefore, Tosfos would rule that the person who breaks the utensil before the arrow hits it is liable.
The Ketzos ha'Choshen suggests that according to his understanding, in such a case perhaps the second person will not be liable. Rather, the person who shot the arrow will be liable, similar to the law in the case cited by the Gemara in which a person throws a utensil down from a high place and another person breaks it before it hits the ground. Just as the second person is not liable in that case because of "Basar me'Ikara Azlinan" and it is considered as though he broke a utensil that was already broken, so, too, when one shoots an arrow at a utensil and another person breaks the utensil before the arrow hits it, "Basar me'Ikara Azlinan" dictates that the second person broke a broken utensil. It makes no difference whether the utensil would have been broken by the "Guf" of the person or by the "Ko'ach" of the person. In either case, someone else broke it since, according to the laws of Adam ha'Mazik, there is no difference between "Kocho" and "Gufo" -- a person is equally liable for damage caused by his "Ko'ach" and his "Guf." Only in the case of damage caused by an animal is there a difference between "Kocho" and "Gufo" because of the Halachah l'Moshe mi'Sinai of Tzeroros.
(The Ketzos ha'Choshen suggests that some Rishonim may agree with his way of understanding. He cites the Rosh (1:1) and Nimukei Yosef (21a). However, other Acharonim reject his proofs.)
HAGA'ON RAV YISRAEL ZEV GUSTMAN zt'l (in KUNTRESEI SHI'URIM 10:17) finds a Rishon who apparently supports the assertion of the Ketzos ha'Choshen. The RASHBA here mentions that the RIF rules that "Basar me'Ikara Azlinan," and therefore if someone throws a utensil from the roof and someone else shatters it before it hits the ground, the second person is exempt. Nevertheless, the Rif quotes part of the conclusion of the Gemara (18a) which apparently is necessary only if there is no rule of "Basar me'Ikara Azlinan"! The Gemara there proves that "Basar me'Ikara Azlinan" from the Beraisa cited here (17b) which teaches that if hens were pecking at the rope of a bucket and the rope broke and the bucket fell and broke, the owner of the hens must pay Nezek Shalem. The Gemara says that this ruling proves that "Basar me'Ikara Azlinan," because otherwise the owner should have to pay only Chatzi Nezek for the bucket, since the bucket broke by falling and breaking. Rav Bibi bar Abaye answers that the bucket did not fall and break, but rather the hen pushed the rope and the bucket until the bucket broke; since the hen pushed the bucket itself, the owner must pay Nezek Shalem.
The Rif cites Rav Bibi bar Abaye's answer, that the reason why the owner of the hen must pay Nezek Shalem is that the hen pushed the bucket itself, and not because of "Basar me'Ikara Azlinan." If the Rif rules that "Basar me'Ikara Azlinan," why does he quote the reason of Rav Bibi bar Abaye?
The RASHBA answers that the Rif may rule that even if "Basar me'Ikara Azlinan" applies, that only makes it as though all of the damage happened at the time the bucket first started to fall. Nevertheless, since the hens did not touch the bucket itself but only the rope, it is called Tzeroros. That is why the Rif needs to rule that the hen actually pushed the bucket itself and broke it, and he does not write that the hen pushed the rope and thereby caused the bucket to break.
The Rashba's explanation is a strong support for the logic of the Ketzos ha'Choshen, that even if "Basar me'Ikara Azlinan," the case is still considered a case of Tzeroros ("Kocho") as long as the animal did not touch the object that broke, but touched something else which then caused the object to break.
(The Rashba also agrees with the difference of Tosfos, however, that when the object which broke was not set into motion, the principle of "Basar me'Ikara Azlinan" does not apply. He merely adds that even when that object was set into motion, "Basar me'Ikara Azlinan" still does not remove the damage from the category of Tzeroros unless the animal actually touched the object.)

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