GEMARA BAVA KAMA 5771

Shiuir #19: Rav Natan (15b)

The Scope of Damage Prevention

Based on shiurim by Rav Reuven Taragin

I)  The Prohibition

            Although 'chatzi nezek' can no longer be officially collected (see last shiur), the gemara (15b) dictates the excommunication of a mazik's owner until he 'removes' the danger (by killing the animal, according to Rashi).  As basis for the ban, the gemara quotes Rav Natan's prohibition against raising menacing dogs or setting up rickety ladders.  Violation of the prohibition warrants the ban.

II)  Assumption

            The Shitta Mekubetzet (s.v. Mi-derebbe) and the Yere'im (siman 310) point out that Rav Natan's usage of the verse 'Ve-asita Ma'akeh le-gagekha; lo tasim damim be-vetekha' (Devarim 22:8 - 'And you shall make a railing for your roof; you shall not put blood in your house'), as basis for his prohibition, significantly expands the verse's scope.  The verse itself mandates only the installation of a guardrail surrounding a dangerous porch and includes no reference to dangerous objects.  Rav Natan obviously understood the porch case not as a limited exception, but as an archetype of all potentially dangerous situations.

III)  Basis

            Basis for his expansion can be found in the Sifrei (ibid. 19) which derives from the verse the responsibility to cordon off even one's pit.[1]  It seems that this issue was debated by the gemara (51a) which suggests two possible explanations for the limitation of the verse to homes of at least ten tefachim (handbreadths) height.  Initially, the gemara views the height requirement as reflective of the verse's relevance to only life-threatening situations.[2]  In response, the gemara explains the requirement as reflective of the verse's pertinence to only bona fide homes, that are at least ten tefachim high (as is the case regarding mezuza).  Rashi (s.v. Lav) justifies this suggestion by pointing out that the verse refers explicitly to homes.[3]

            A careful reading of Rav Natan's formulation reveals what he saw as the basis for his expansion.  Rav Natan quotes as his source not the aseh (positive commandment) with which the verse opens, but the Lav (negative prohibition) that concludes the verse.  This can be attributed to the broader formulation of the Lav which refers to any situation of potential 'damim' (bloodshed).

IV)  Two Tracks

            The significance of Rav Natan's linkage to the Lav hinges on the relationship between the Lav and aseh.  According to the Ramban (Kiddushin 34a s.v. Ve-ha), who assumes that the Lav merely reaffirms the aseh, once included through the Lav Rav Natan's cases fall under the rubric of the aseh as well.  However, according to Tosafot (ibid. s.v. Ma'akeh) and most Rishonim, who suggest distinctions between the aseh and the Lav, Rav Natan's cases may be prohibited by the Lav alone.  The Semak (siman 152)[4] suggests such a distinction by limiting the aseh to the particular situation it specifies - containing a porch.  The Lav, though, beyond confirming the aseh, mandates treatment of all dangerous situations - including those of Rav Natan. 

            The Netziv[5] uses this distinction to explain the Sifrei which requires safeguarding a pit, yet excludes buildings not normally used for lodging.  The Yere'im (siman 334) establishes the criteria for chiyuv to be the likelihood of danger, which depends on the frequency of use.  A pit must be protected, for it is frequented more than a house not designated for lodging.  The Devar Avraham[6], on the other hand, assumes the criteria to be a bona fide home and limits the pit case to one located in the vicinity of the home and, thus, considered part of it.  The Netziv, adopting the Semak's distinction between the aseh and the Lav, suggests that while the exclusion of the pseudo-home was regarding only the aseh, the inclusion of the pit was only regarding the Lav.  Although the aseh relates only to bona fide homes, the Lav relates to all dangerous situations.

            The Chayei Adam[7] uses this distinction to limit the scope of the berakha recited when constructing the rail.  Since birkhot mitzva are made only when fulfilling mitzvot aseh, he limits the berakha to the protection of porches, as opposed to other dangerous objects or situations.[8]

            This view of Rav Natan's reference to the Lav as exclusive can account for Tosafot's suggested distinction between the Lav and aseh.  Tosafot claim that, although the aseh applies irrespective of the circumstances of the porch's construction, the Lav pertains only to situations where the owner personally creates the danger with intent to neglect safety measures.[9]  Assuming the limitation of Rav Natan's statement to only the Lav, basis for Tosafot's understanding of the Lav's uniqueness can be brought from Rav Natan's emphasis on 'raising' ('yegadel') of menacing dogs and 'setting up' ('ya'amid') of rickety ladders.

            Acceptance of the distinctions of both Tosafot and the Semak (who quotes both together) we get a clear understanding of the relationship between the aseh and the Lav.  The aseh applies only to porches, under all circumstances; the Lav applies to all dangerous situations, but only when created with improper intent. 

Sources and Questions for shiur #20 Bava Kama on Tzerorot

Sources:

1. Gemara BK (17a) Mishna … (19a) Teiku.

Rambam in his commentary to the mishna.

Rabbenu Chananel (19a) "Ba'i R. Abba bar Mammal … be-teiku."

2. Tosafot (17b) s.v. Nover.

Rashba (17b) s.v. Ve-tinfu.

Rashi (18b) s.v. De-dachik.

3. Rashi (17b) s.v. She-bazav; Yerushalmi 2:1 "R. Lazar … kofer."

Tosafot s.v. Kol; Shitta Mekubetzet in the name of Rabbenu Yehonatan s.v. Ve-Rava.

4. Yerushalmi 2:2 "Tarnegol ha-porei'ach … nezek shalem."

Questions:

1.  What aspect of tzerorot damages is 'diminished' and responsible for the reduction to half-nezek?

2.  How do most Rishonim understand R. Abba bar Mammal's question on (19a)?  How does the Rabbenu Chananel's explanation differ?

3.  Can there be tzerorot in avot other than regel?

4.  Which explanation of the 'zav' comparison seems more logical - Rashi's or Tosafot's?

5.  Does the Yerushalmi agree or disagree with the Bavli's view of an animal which breaks a utensil with its 'braying?'