Bava Kamma 4A

ולא ראי השן ⁠– שאין כוונתו להזיק, כראי הקרן ⁠– שכוונתו להזיק.

And the defining characteristic [re’i] of the category of Eating, where it is not the objective of the animal to cause damage, is not similar to the defining characteristic of the category of Goring, where the objective of the animal is to cause damage.

ולאו קל וחומר הוא ⁠– ומה שן, שאין כוונתו להזיק ⁠– חייב; קרן, שכוונתו להזיק ⁠– לא כל שכן? איצטריך, סלקא דעתך אמינא: מידי דהוה אעבד ואמה ⁠– עבד ואמה, לאו אף על גב דכוונתן להזיק, אפילו הכי פטירי? הכי נמי לא שנא.

The Talmud asks: But isn’t it possible to derive Goring from Eating by means of an a fortiori inference: If in a case of Eating, where it is not the objective of the animal to cause damage, its owner is liable, with regard to Goring, where the objective of the animal is to cause damage, should the owner not all the more so be liable? The Talmud answers: Nevertheless, it was necessary for the Torah to state the case of Goring, as it might enter your mind to say that the owner is exempt, just as he is exempt in the case where his slave or female slave causes damage. When a slave or female slave causes damage, is it not so that although their objective is to cause damage, even so their owners are exempt from liability; and so too, when one’s animal causes damage, it is no different. To dispel this notion, the Torah explicitly states that one is liable for damage caused by the primary category of Goring.

אמר רב אשי: אטו עבד ואמה לאו טעמא רבה אית בהו? שמא יקניטנו רבו, וילך וידליק גדישו של חבירו, ונמצא זה מחייב את רבו מאה מנה בכל יום!

Rav Ashi said: Is that to say that in a case where one’s slave or female slave causes damage there is not a substantial reason to exempt the master? In that case there is concern that perhaps his master will provoke him and in retribution he will go and set fire to another’s stack of grain, and it is found that this slave renders his master liable to pay 100 maneh, 10,000 dinars, each day. Therefore, there is no basis for the notion that an ox that gores would be exempt just as a slave is exempt, as perhaps, fundamentally, one is liable to pay for damage caused by his slave. A master is exempt from payment to prevent a situation where a slave would exploit that situation to take revenge against his master.