ATTEMPTS TO ANSWER RAVA'S QUESTION [line 2]
Answer #2 (Beraisa): If chickens were pecking at the rope of a bucket, and the rope snapped and the bucket broke, they pay full damage.
This proves that it depends on the beginning!
Rejection #1: No, the Beraisa teaches that they pay full damage for the rope.
Question: It is abnormal to peck at a rope!
Answer: There was dough on the rope.
Objection: If he pays for the rope, why did the Beraisa mention the bucket?!
Rejection #2: The Beraisa is like Sumchus, who says that Tzeroros pay full damage.
Objection (Seifa): If a fragment flew off (the bucket) and broke a Kli, he pays full damage for the first Kli, and half-damage for the second;
According to Sumchus, he should pay full damage for both Kelim!
Suggestion: Perhaps Sumchus distinguishes between impetus and impetus of impetus (the damager set something in motion, it set something else in motion that later damaged).
Rejection: Rav Ashi never resolved this!
Question (Rav Ashi): Does Sumchus consider impetus of impetus like impetus, or not?
If the Beraisa is like Sumchus, this shows that he does not consider it as impetus!
Conclusion: The Beraisa is like Chachamim. Impetus is like bodily damage.
Rejection (Rav Bivi bar Abaye): No. The case is, the chicken was pushing the bucket the entire time, until it broke.
DO TZEROROS PAY MIN HA'ALIYAH? [line 17]
Question (Rava): Is half-damage of Tzeroros paid from ha'Aliyah (even above the value of the damager)?
We never find half-damage that pays from ha'Aliyah;
On the other hand, we never find normal damage that pays mi'Gufo (only up to the value of the damager)!
Answer #1 (Beraisa): Dancing (of chickens) is not Mu'ad;
Some say, it is Mu'ad.
Objection: Surely, dancing is Mu'ad!
Correction: Rather, the chickens danced and strewed up pebbles, which broke a Kli.
Suggestion: The Tana who says that it is not Mu'ad holds that it pays from ha'Aliyah. The other Tana says that it does not.
Rejection: No, they argue like Sumchus and Chachamim (like above).
Answer #2 (Mishnah): If a dog took a cake (with a coal inside) to a pile of grain, and it ate the cake and burned the grain, it pays full damage for the cake and half-damage for the grain.
Suggestion: This is because burning the grain is like Tzeroros.
(Beraisa): Half-damage is paid (for the grain) up to the value of the dog.
This settles Rava's question!
Objection: This cannot be! R. Elazar holds that full damage is paid even for the grain. We never find full damage mi'Gufo! (Rava asks only according to Chachamim. Surely, Sumchus, who obligates full damage for Tzeroros, holds that it pays from the Aliyah, like a Mu'ad.)
Rather, we must say that the dog acted abnormally with the coal. R. Elazar holds like R. Tarfon, who says that Keren in the victim's premises pays full damage.
Defense #1 (of Answer #2): We need not say that R. Elazar holds like R. Tarfon, or that the damage was abnormal;
We can say that he holds like Sumchus, and like R. Yehudah (who says that half the obligation of a Mu'ad is like a Tam. The Tam part only pays mi'Gufo. Rava's question is settled, like above.)
Objection (Rav Sama brei d'Rav Ashi): R. Yehudah said so in cases where the animal was initially Tam. We have no source to say this about something (Tzeroros, according to Sumchus) that is Mu'ad from the beginning!
Defense #2 (Rav Sama): R. Elazar says that it became Mu'ad for damage through Tzeroros.
The first Tana holds that Tzeroros cannot become Mu'ad. R. Elazar holds that they can.
Question: Rava never resolved this!
Question (Rava): Can Tzeroros become Mu'ad?
According to Rav Sama, Chachamim say that they cannot, and R. Elazar says that they can!
Answer: Rava asked (whether Tzeroros can become Mu'ad) according to Chachamim who argue with Sumchus. R. Elazar and his Chachamim (those who argue with him) all hold like Sumchus.
Question: If R. Eliezer's Chachamim hold like Sumchus, they should obligate full damage!
Answer: Chachamim obligate half-damage for the cake because it was abnormal, and it did not become Mu'ad for this. R. Elazar and his Chachamim argue like R. Tarfon and his Chachamim.
Question: R. Tarfon said that Keren in the victim's premises pays full damage. Do we have any source that it pays only mi'Gufo?
Answer: Yes! He learns from a Kal va'Chomer, from Keren in Reshus ha'Rabim. The principle of Dayo (a Kal va'Chomer cannot teach more than the source) dictates that it only pays mi'Gufo.
Question: But R. Tarfon disagrees with the principle of Dayo!
Answer: He argues only when the Kal va'Chomer does not teach anything new (e.g. we knew half-damage without the Kal va'Chomer). Once we learn a Chidush (e.g. full damage), he agrees to Dayo.
CAN TZEROROS BECOME MU'AD? [line 18]
Question (Rava): Can Tzeroros become Mu'ad?
Do we compare them to Keren (they can become Mu'ad)?
Or, since they are a Toldah of Regel, they cannot become Mu'ad.
Answer #1 (Beraisa): Dancing (of a chicken) is not Mu'ad;
Some say, it is Mu'ad.
Objection: Surely, dancing is Mu'ad!
Correction: Rather, a chicken danced and strewed up pebbles.
Suggestion: The chicken has done this three times. They argue about whether or not it becomes Mu'ad.
Rejection: No, they argue about the first time it happens, like Sumchus and Chachamim argue.
Answer #2: Amora'im argue about Rava's question.
(Rav Yehudah): If an animal excreted on a dough, it pays full damage;
R. Elazar says, it pays half-damage.
Suggestion: The animal has done this three times three times; they argue about whether or not it becomes Mu'ad.
Rejection: No. They argue the first time it happens, like Sumchus and Chachamim argue.
Question: But this is abnormal! (Why does Rav Yehudah obligate full damage?)
Answer: It had no other place to excrete, so it was normal.
Question: Rav Yehudah should have said 'the Halachah follows Sumchus', and R. Elazar should have said 'the Halachah follows Chachamim'! (Why did they teach about a particular case?)
Answer: There is a Chidush in the law of excrement. One might have thought that since it comes from the body, all agree that it is like bodily damage. They teach that this is not so.
Answer #3 (Rami bar Yechezkel - Beraisa): If a chicken stuck its head into a glass Kli and cackled, breaking it, it pays full damage;
(Rav Yosef): If a horse or donkey neighed and broke Kelim, it pays half-damage.
Suggestion: They did so three times. They argue about whether or not it becomes Mu'ad.