But if an ox is entirely rendered forewarned, you do not find an element of innocuousness with regard to it at all. If it is forewarned with regard to goring with either horn, its status of innocuousness is completely revoked.

§ The mishna teaches that Rabbi Eliezer says: An ox has no sufficient safeguarding at all other than slaughtering it with a knife. Rabba said: What is the reason for the opinion of Rabbi Eliezer? It is as the verse states with regard to a forewarned ox: “And the owner has not secured it” (Exodus 21:36), meaning that once it is rendered forewarned the owner no longer has any sufficient manner of safeguarding this animal, and the owner is responsible for all damage it causes.

Abaye said to Rabba: If that is so, does that which is written with regard to a pit: “And if a man shall open a pit, or if a man shall dig a pit and not cover it” (Exodus 21:33), also mean that once a pit has been dug the owner no longer has any adequate way of covering this pit, which would exempt its owner from paying damages?

And if you would say that indeed that is the halakha, but didn’t we learn in a mishna (52a) that if he covered the pit appropriately, and an ox or a donkey fell into it and died, he is exempt? Evidently, a pit can be covered adequately.

Rather, Abaye rejected Rabba’s explanation of Rabbi Eliezer’s opinion, and said that this is the reason for the opinion of Rabbi Eliezer: As it is taught in a baraita that Rabbi Natan says: From where is it derived that one may not raise a vicious dog in his house, and that one may not set up an unstable ladder in his house? As it is stated: “You shall not bring blood into your house” (Deuteronomy 22:8), which means that one may not allow a hazardous situation to remain in his house. Similarly, a person should not keep a forewarned ox in his possession, as it is dangerous. This is why Rabbi Eliezer rules that no level of safeguarding is sufficient for it; the ox should be slaughtered so that it will not cause damage.

MISHNA: In the case of an innocuous ox that gored and killed a cow, and the cow’s fetus was found dead at its side, and it is not known whether the cow gave birth before the ox gored it and the fetus’s death is unrelated to the goring or whether it gave birth after the ox gored it and the fetus died on account of the goring, the owner of the ox pays half the cost of the damage for the cow and one-quarter of the cost of the damage for the offspring. Since it is uncertain whether the ox was responsible for the death of the fetus, in which case he would pay half the damages, its owner pays only half the amount for the fetus that he would ordinarily be required to pay, i.e., one-quarter.

And likewise, there is uncertainty in the case of an innocuous cow that gored an ox, and the cow’s newborn offspring was found at its side dead or alive, and it is not known whether the cow gave birth before it gored the ox or whether the cow gave birth after it gored. When damage is caused by an innocuous animal, the liability of the owner is limited to the value of the animal that gored. Therefore, half the cost of the damage is paid from the value of the cow, as in the standard case of an innocuous animal. And if that does not suffice to pay for half the cost of the damage, one-quarter of the cost of the damage is paid from the offspring. Since it is uncertain whether the offspring was part of the cow at the time the cow gored, the owner pays only half of what he would pay if it were certain that it was part of the cow.

GEMARA: Rav Yehuda says that Shmuel says: This ruling in the mishna is the statement of Sumakhos, who says: Property of uncertain ownership is divided by the two parties. But the Rabbis say that this is the significant principle of monetary law: The burden of proof rests upon the claimant, and the disputed sum is not divided. According to the Rabbis, in the cases of uncertainty in the mishna, no payment is made for the fetus or from the offspring, respectively.

The Gemara asks: Why do I need for the Rabbis to say the words: This is the significant principle of monetary law? Why not just state the principle? The Gemara answers: It was necessary to say them because even in a case where the injured party states: I am certain that such and such occurred, and the one liable for the damage says: Perhaps it was otherwise, without definitively refuting the claim against him, the burden of proof rests upon the claimant. Although the injured party claims with certainty that he is correct and the defendant’s claim is only speculative, the definite claim still does not render the defendant liable to pay, absent proof.

Alternatively, the phrase: This is the significant principle of monetary law, was necessary for instances such as this, as it was stated: In the case of one who sells an ox to another and the ox is found to be one that habitually gores, Rav says that this is considered to be a mistaken transaction, since the purchaser can claim that he bought the ox specifically for labor, and an ox that gores is not suitable for such tasks. And Shmuel says: The seller can say to him: I sold it to you for slaughter, and the fact that it gores is immaterial.

The Gemara asks: Why are Rav and Shmuel speculating about the purpose of the sale? But let us simply see if the purchaser is a person who buys oxen for plowing or a person who buys oxen for slaughter. The Gemara answers: No, it is necessary for them to engage in a dispute in the case of a person who buys oxen for both this and for that reason, and in this instance it was unclear for which purpose it was intended.

The Gemara asks: But let us see what the purchase price was: If he paid the price of an ox fit for plowing, which is a large amount of money, then it can be assumed it was intended for plowing. But if he paid the price of an ox for slaughtering, which is a much smaller amount, it can be assumed that it was sold for slaughtering.

The Gemara answers: No, it is necessary for them to engage in a dispute in a case where the cost of meat rose and an ox purchased for slaughtering stands at the same price as an ox purchased for plowing. In that case, Rav and Shmuel dispute whether the purchaser can claim that the transaction was made in error, or whether the seller can claim that he sold it to be slaughtered and the purchaser must provide proof for his claim.

The Sages said: