Bava Kamma - Daf 51
- Fatal impact from a pit less than ten tefachim deep (measuring from the ox’s abdomen)
The Gemara relates an incident where an ox once fell into a ditch which was six tefachim deep. When the owner shechted it immediately, Rav Nachman declared it a tereifah because of its injury, and commented that the owner should have waited twenty-four hours to demonstrate it was not a tereifah. The Gemara initially infers that Rav Nachman holds: יש חבטה בפחות מעשרה – there is potentially fatal impact for a fall of even less than ten tefachim, but ultimately disproves this from the law of מעקה, which is only required for an elevation of ten tefachim. Therefore, the Gemara clarifies that Rav Nachman agrees that a fall of ten tefachim is required to kill an animal but reasoned that since an animal’s abdomen is four tefachim above the ground, and the ditch was six tefachim deep, it emerges that the animal fell ten tefachim into the ditch. The Mishnah, which holds the digger responsible for an animal’s death only at a depth of ten tefachim, is דאיגנדר לבור – where [the ox] was lying down and rolled into the pit, and did not fall more than the depth of the pit.
- Multiple people involved in digging a bor
A Baraisa taught that if one person digs a pit nine tefachim deep, and a second person digs a tenth tefach, the Rabbonon say: האחרון חייב – the last person is exclusively liable for all injury or death caused by the pit. Rebbe says: אחר אחרון למיתה – The victim goes after the final digger to collect payment for his animal’s death, ואחר שניהם לנזקין – but goes after both diggers to collect for injuries.
A Baraisa teaches that if one dug ten tefachim, another deepens it to twenty tefachim, and a third person deepens it to thirty, they are jointly liable for its damages. This seems to contradict another Baraisa, which states that if one dug ten tefachim and another coated it with plaster (making it narrower, with more foul air), the second person alone is liable. The Gemara suggests that the first Baraisa is Rebbe’s opinion, and the second is the Rabbonon’s. Rav Zevid answers that היכא דעבד קמא שיעור מיתה – where the first one made it the measure sufficient for death, the Rabbonon agree they are all liable, and the second Baraisa is a case where the pit did not have sufficient foul air to kill before it was plastered.
- When a bor of two partners becomes the second one’s responsibility
The Mishnah taught regarding a bor of two partners, that if one passed by it and did not cover it, then the second one passed by and did not cover it, the second person is liable. The Gemara asks when it becomes the second person’s responsibility, and two opinions are given: (1) משמניחו משתמש – he is exempt when he left [the second person] using the pit. (2) משימסור לו דליו – when he hands over its cover to [the second person]. After the Gemara establishes that this reflects a machlokes Tannaim, the first opinion being the Rabbonon’s, and the second, Rebbe Eliezer ben Yaakov’s, it explains that the machlokes is rooted in bereirah (retroactive determination): Rebbe Eliezer relies on bereirah, so when one partner is using the pit, he is only using his portion and is not “borrowing” his partner’s portion. Therefore, using it alone does not amount to assuming sole responsibility for the pit (and the other is only exempt if he handed him the cover). The Rabbonon do not rely on bereirah, so one person using the pit is “borrowing” his partner’s portion and becomes solely responsible for its damages.
