(Mishnah): If Se'or of Chulin fell into a dough, and it was enough to ferment it, and afterwards, Se'or of Terumah or Kilai ha'Kerem fell in, and it was enough to ferment it, the dough is forbidden;

If Se'or of Chulin fell into a dough and fermented it, and afterwards, Se'or of Terumah or Kilai ha'Kerem fell in, and it was enough to ferment it, the dough is forbidden;

R. Shimon permits it.

(Gemara - Chananyah citing R. Yochanan): Also the first law (the forbidden Se'or fell in before the Chulin Se'or did) is an argument (R. Shimon permits).

Assumption (R. Yonah): We (Bnei ha'Yeshivah) thought to say, when do they argue? It is when this fermented all its strength (was in the dough long enough to ferment as much as it can), and this [fermented] all its strength, and the Chulin Se'or fell first (the Asur Se'or is li'Fgam, i.e. detrimental);

However, if the Terumah Se'or fell first, the dough already fermented [due to the Terumah, so all forbid].

Every [Isur] that gives taste, whether li'Fgam or li'Shevach (beneficial), is forbidden. R. Meir says so;

R. Shimon says, li'Shevach is forbidden, and li'Fgam is permitted.

(Reish Lakish): When do they argue? It is when it improved [the taste], and afterwards detracted, but if detracted, and afterwards improved, even R. Meir agrees (that it is permitted).

(R. Yochanan): There is no difference. If it improved, and afterwards detracted, it is the same as if it detracted, and afterwards improved; they argue.

(Mishnah): Barley that fell into a pit of water, even if it made the water smell, the water is permitted (for it is li'Fgam).

Question: What is [the status of] this Mishnah? (Is it unanimous, or do Tana'im argue about it?)

Answer #1 (R. Yochanan): It is an argument.

Answer #2 (Reish Lakish): It is like everyone.

And so said R. Yosi bei R. Bun like these teachings, that R. Yochanan says that it is an argument, and Reish Lakish said that it is like everyone.

Question (R. Yonah, against Reish Lakish): Did we (Bnei ha'Yeshivah) not hold that they argue when this fermented all its strength, and this [fermented] all its strength, and the Chulin Se'or fell first, but if the Terumah Se'or fell first, the dough already fermented [due to the Terumah, so all forbid? We explained this like RIDVAZ.]

And even if the Chulin Se'or fell first, it is as if it detracted from the beginning! (Reish Lakish holds that R. Meir forbids only if it initially improved - SHA'AREI TORAS ERETZ YISRAEL).

Answer (R. Yonah): This woman [making the dough] does not [put enough Se'or to] fully ferment [lest it ferment too much]. She omits Mashehu (a drop. The Terumah Se'or fermented) that Mashehu, so it is as if it improved, and afterwards detracted (R. SHLOMO SIRILIYO).

Rebuttal: If it only improved [fermented the last Mashehu], and did not detract, is this anything?! (Surely Terumah does not forbid due to Mashehu Shevach, rather, due to the Pegam, unlike Reish Lakish! - MAHARA FULDA, GRA.)

Question (R. Yonah): What is the difference between if it improves from this (Isur) and from this (Heter), and when there is Pegam from this and from this?! When it improves from this and from this, it is forbidden (R. Shimon agrees in the Reisha, even though the Isur improved only part) and when there is Pegam from this and from this (in the Seifa, R. Shimon) permits! (If he attributes all the Pegam to the Isur, in the Reisha he should attribute all the Shevach to the Isur!),

Answer (R. Mana): When it improves from this and from this, you view the Heter as if it is not; the Isur has enough to forbid. When there is Pegam from this and from this, you view the Heter as if it is not; the Isur is not enough to forbid. (I.e. there is no reason to forbid; R. Shimon says that only Shevach is a reason to forbid.)