Bava Batra — Daf 84a

דאמר ליה אילו לא אוניתן לא הוה מצית הדרת בך השתא דאוניתן מצית הדרת בך ותנא תונא יפות ונמצאו רעות לוקח יכול לחזור בו ולא מוכר

ואמר רב חסדא מכר לו שוה שש בחמש והוזלו ועמדו על ג' מי נתאנה מוכר מוכר יכול לחזור בו ולא לוקח דא"ל אילו לא אוניתן לא הוה מצית הדרת בך השתא מצית הדרת בך ותנא תונא רעות ונמצאו יפות מוכר יכול לחזור בו ולא לוקח

מאי קא משמע לן מתני׳ היא אי ממתני' הוה אמינא דלמא דרב חסדא תרוייהו מצו הדרי בהו ומתני' הא אתא לאשמועינן דלוקח יכול לחזור בו

דס"ד אמינא משום דכתיב (משלי כ, יד) רע רע יאמר הקונה:

שחמתית ונמצאת לבנה כו': אמר רב פפא מדקתני לבנה ש"מ האי שמשא סומקתי היא תדע דקא סמקא צפרא ופניא והאי דלא קא חזינן כוליה יומא נהורין הוא דלא ברי

מיתיבי (ויקרא יג, כה) ומראהו עמוק מן העור כמראה חמה עמוקה מן הצל והתם לבן הוא כמראה חמה ולא כמראה חמה כמראה חמה דעמוקה מן הצל ולא כמראה חמה דאילו התם לבן והכא אדום

ולמאי דסליק דעתין מעיקרא הא קא סמקא צפרא ופניא בצפרא דחלפא אבי וורדי דגן עדן בפניא דחלפא אפתחא דגיהנם ואיכא דאמרי איפכא:

יין ונמצא חומץ שניהן יכולין לחזור בהן: לימא מתניתין רבי היא ולא רבנן דתניא

he [the buyer] can say unto him: If you had not imposed upon me, you would have had no right to withdraw; can you have the right to withdraw now that you have imposed upon me? And the Tanna [of our Mishnah, who taught that 'if wheat was sold as] GOOD AND IT TURNED OUT TO BE BAD, THE BUYER MAY WITHDRAW,' but not [inferentially] the seller,  confirms [what has just been said]. R. Hisda further stated: [If] one has sold to another what was worth six for five and the price fell  to three, the seller, since he has been imposed upon, may withdraw, but not [so] the buyer; because [the seller] can say unto him: If you had not imposed upon me you would have had no right to withdraw; can you have the right to withdraw now? And the Tanna [of our Mishnah, who taught that 'if wheat was sold as] BAD AND IT TURNED OUT TO BE GOOD, THE SELLER MAY WITHDRAW,' but not [inferentially] the buyer,  confirms [this statement]. What does he  come to teach us? [Surely] this [statement of his may be inferred from] our Mishnah! — If  [it had to be inferred] from our Mishnah, it could have been said that [in the cases dealt with in the statement] of R. Hisda, both  may perhaps withdraw; and [that the first clause of] our Mishnah comes to teach us that  the buyer may withdraw;  for [without this Mishnah] it might have been said that [he cannot], because it is written: 'It is bad, it is bad', saith the buyer. [IF ONE HAS SOLD WHEAT AS] DARK-COLOURED AND IT TURNED OUT TO BE WHITE, etc. R. Papa said: Since white is given [as the contrast of the other colour]  it may be inferred that the sun is dark-red.  This can be proved [from the fact] that the sun is red at sunrise and at sunset. The reason why we do not see it [red] all day, is [because] our eyesight is not strong [enough].  An objection was raised: And the appearance thereof be deeper than the skin,  [that means], like the appearance of sunlight [which is] deeper than the shadow.  Surely there  [the appearance] was white,  [how, then, could the sun be said to be red]?  — Like the appearance of the sun [in one respect], and not like the appearance of the sun [in another respect]. Like the appearance of the sun, [in] that it is deeper than the shadow; and not like the appearance of the sun [in another respect], for there,  it is white and here  it is red. But according to our previous assumption,  is not the sun red at sunrise and at sunset?  — [It is red] at sunrise, because it passes by the roses of the Garden of Eden;  at sunset, because it passes the gate of Gehenna.  Others reverse [the answer]. [IF LIQUID HAS BEEN SOLD AS] WINE, AND IT TURNED OUT TO BE VINEGAR … BOTH MAY WITHDRAW. Must it be said that our Mishnah is [in agreement with] Rabbi and not [with] the Rabbis?  For it has been taught: