Study Bava Batra folio 78A with parallel Hebrew-English text, traditional commentary, and modern study tools. Free access to Babylonian Talmud online.
Text Excerpt
וכי תימא ביטול מקח לרבנן לית להו, ולא?! והתנן, רבי יהודה אומר: המוכר ספר תורה, בהמה ומרגלית – אין להן אונאה. אמרו לו: לא אמרו אלא את אלו!
And if you would say that the Rabbis do not hold that in a case of exploitation of less than 1/6th one must return the money and that if it was more than 1/6th there is nullification of the transaction, can it be maintained that they do not accept these halakhot? But didn’t we learn in a Mishnah (Bava Metzia 56b) that R' Yehuda says: Even in the case of one who sells a Torah scroll, an animal, or a pearl, these items are not subject to the halakhot of exploitation, as they have no fixed price. The Rabbis said to him: The early rabbis stated that only these items listed earlier in the Mishnah, i.e., land, slaves, and documents, are not subject to the halakhot of exploitation. Therefore, the Rabbis should agree that the sale of the yoke is nullified.
מאי ״אין דמים ראיה״ נמי דקתני – דהוי ביטול מקח. ואיבעית אימא: כי אמור רבנן אונאה וביטול מקח – בכדי שהדעת טועה, אבל בכדי שאין הדעת טועה – לא; אימור מתנה יהב ליה.
The Talmud answers: What is the meaning of the Mishnah that teaches that according to the opinion of the Rabbis the sum of money is not proof? This means that the transaction is nullified. And if you wish, say instead that the sale of the yoke is not nullified, because when the rabbis spoke of exploitation and the nullification of a transaction, they meant that these halakhot apply only in a case where the difference in price is an amount about which one could be mistaken and believe that this is the correct price. But when the difference in price is so great a sum that one could not be mistaken, this sale is not subject to the halakhot of exploitation. In that case, one must say that the buyer gave the extra money to the seller as a gift; he could not have thought that this was the actual price of the object.