Quotation for Yadayim 4:7
אוֹמְרִים צְדוֹקִין, קוֹבְלִין אָנוּ עֲלֵיכֶם, פְּרוּשִׁים, שֶׁאַתֶּם מְטַהֲרִים אֶת הַנִּצּוֹק. אוֹמְרִים הַפְּרוּשִׁים, קוֹבְלִין אָנוּ עֲלֵיכֶם, צְדוֹקִים, שֶׁאַתֶּם מְטַהֲרִים אֶת אַמַּת הַמַּיִם הַבָּאָה מִבֵּית הַקְּבָרוֹת. אוֹמְרִים צְדוֹקִין, קוֹבְלִין אָנוּ עֲלֵיכֶם, פְּרוּשִׁים, שֶׁאַתֶּם אוֹמְרִים, שׁוֹרִי וַחֲמוֹרִי שֶׁהִזִּיקוּ, חַיָּבִין. וְעַבְדִּי וַאֲמָתִי שֶׁהִזִּיקוּ, פְּטוּרִין. מָה אִם שׁוֹרִי וַחֲמוֹרִי, שֶׁאֵינִי חַיָּב בָּהֶם מִצְוֹת, הֲרֵי אֲנִי חַיָּב בְּנִזְקָן. עַבְדִּי וַאֲמָתִי, שֶׁאֲנִי חַיָּב בָּהֶן מִצְוֹת, אֵינוֹ דִין שֶׁאֱהֵא חַיָּב בְּנִזְקָן. אָמְרוּ לָהֶם, לֹא. אִם אֲמַרְתֶּם בְּשׁוֹרִי וַחֲמוֹרִי, שֶׁאֵין בָּהֶם דַּעַת, תֹּאמְרוּ בְּעַבְדִּי וּבַאֲמָתִי, שֶׁיֵּשׁ בָּהֶם דָּעַת. שֶׁאִם אַקְנִיטֵם, יֵלֵךְ וְיַדְלִיק גְּדִישׁוֹ שֶׁל אַחֵר וֶאֱהֵא חַיָּב לְשַׁלֵּם:
The Sadducees say: We denounce you, Pharisees, for you declare pure the stream [which flows when a liquid is poured from a clean vessel into an unclean one]! The Pharisees say: We denounce you, Sadducees, for you declare pure a channel of water which flows from a cemetery! The Sadducees say: We denounce you, Pharisees, for you say, if my ox or my donkey cause any damage, I am liable [to compensate], but if my manservant or maidservant cause any damage, I am exempt [from compensating]! Just as with regard to my ox and my donkey, with which I am not obligated to perform any mitzvot, and I am thereby [still] liable [to compensate] for damages, does it not follow with regard to my manservant or maidservant, with whom I am obligated to perform mitzvot, that I should be liable [to compensate] for damages [which they cause]?! They [the Pharisees] said to them, "No. If [i.e. just because] you stated this [law] with regard to my ox or my donkey, which do not have cognitive capabilities, would you say this with regard to my manservant or maidservant who do have cognitive capabilities?!" For [if that logical leap is made], if I offend [one of] them, he may go and set fire to another's [grain] pile, and I will be liable to pay for damages!"
Tosafot on Bava Kamma
The source for this ruling in the Mishna is not as Rashi explained because we are taught in a Mishna in perek Hachovail (later 87a) that as far as a slave and a married woman are concerned, an encounter with them is terrible, for one must pay if he injures them and they do not have to pay if they injure anybody. For if it was so that our Gemara is referring to that Mishna, the Gemara should have mentioned ‘a slave and a married woman’, which would be a direct quotation of that Mishna. Since the Gemara does not mention ‘a slave and a married woman’, it seems that the Gemara is not referring to that Mishna.
Rather, Rabbeinu Tam explains that the Gemara mentioned a slave and a slave woman, because it is referring to a Mishna at the end of Masechet Yadayim (Chapter 4, Mishna 7) that specifically discusses this case of a slave and a slave woman who damage others. And the reason that they are exempt which is because their master may anger them and they will damage another person’s property in order to cause their master to pay that is soon mentioned in our Gemara is explicitly mentioned there in Masechet Yadayim, which also proves that our Gemara is referring to that Mishna.