Suggestion: Perhaps mid'Oraisa he can do Yibum with one and exempt the other. Mid'Rabanan this is forbidden, lest people say that the same applies to Yevamos who fall from different brothers.

Rejection: R. Shimon's Halachah is because of the Ma'amar!

(Beraisa - R. Shimon): If a Ma'amar is like Yibum, he does Yibum with the widow of the second brother. If Ma'amar is not like Yibum, he does Yibum with the widow of the first brother!

Question (Abaye): Don't you distinguish between Zikah when there is one Yavam, and when there are two?

Perhaps R. Shimon says that Zikah is like Yibum only when there is only one Yavam!

Question: R. Shimon does not make such a distinction!

(Beraisa - R. Shimon): The general rule is, if the brother was born before the Yibum, she does neither Chalitzah nor Yibum. If he was born after the Yibum, she does Chalitzah or Yibum.

Suggestion: There is one brother, and she is exempt (when the Yavam was born before the Yibum)!

Answer: No there are two brothers.

Inference: If there was only one brother, she would do Chalitzah or Yibum.

Question: If so, why does R. Shimon teach that Yibum is permitted when the Yavam was born after the Yibum? He should permit even when he was born before, when he is the only brother!

Answer: The entire Beraisa discusses two Yavamim.

Question #1: If so, this is not a general rule!

Question #2 (Rav Oshaya - Mishnah): If two of three brothers were married to sisters, or a woman and her daughter, or a woman and her daughter's daughter, or a woman and her son's daughter (and these two brothers died), the widows do Chalitzah, not Yibum;

R. Shimon exempts.

If R. Shimon holds that Zikah is like Yibum, he may do Yibum with one and exempt the other!

Answer (Rav Amram): True! R. Shimon exempts only the second.

Objection (Beraisa - R. Shimon): Both are exempt.

Answer #1 (Rava): The second widow in each pair is exempt.

Rava misunderstood the Beraisa of four pairs.

Mistake #1: Each brother had only one wife (not four). The two wives were related in one of the four ways.

Mistake #2: According to Rava, it should have said that R. Shimon exempts all four.

Mistake #3: A Beraisa teaches that R. Shimon exempts them because of "Do not take to be Tzaros" - when (sisters) are Tzaros to each other (through Zikah), you cannot marry either.

Answer #2 (Rav Ashi): If they fell to Yibum at different times, one could do Yibum with one and exempt the other;

The case is, they fell to Yibum simultaneously.

R. Shimon holds like R. Yosi ha'Galili, who says that it is possible for two events (e.g. deaths) to occur at the exact same time.

(Rav Papa): R. Shimon argues only when the brother is born after Yibum. R. Shimon agrees that if he was born before, she is exempt.

Both Mishnayos are needed to teach the opinion of Chachamim. The second Mishnah teaches more than the first.

A Beraisa supports Rav Papa and refutes Rav Oshaya.

(Beraisa): Reuven died, leaving a brother Shimon. Levi (another brother) was born before Shimon had a chance to give a Ma'amar, then Shimon died;

The first widow (Reuven's) is exempt due to Eshes Achiv she'Lo Hayah b'Olamo. The second (Shimon's other wife) does Chalitzah or Yibum;

If Shimon gave a Ma'amar before or after Levi was born and then Shimon died, the first widow is exempt due to Eshes Achiv she'Lo Hayah b'Olamo. The second does Chalitzah, but not Yibum;

R. Shimon says, Yibum or Chalitzah with one woman (i.e. the one who did not receive the Ma'amar) exempts her Tzarah.

If Ba'alas ha'Ma'amar (the woman that received the Ma'amar) does Chalitzah, her Tzarah is not exempted.

R. Meir says, if Shimon did Yibum and died, and then Levi was born, both women are exempt from Chalitzah and Yibum. The same applies if Levi was born and then Shimon did Yibum and died;

R. Shimon says, since he (Levi) entered the world when she (the first widow) was permitted, and she was never forbidden to him [while awaiting Yibum], he may do Yibum or Chalitzah with either one.

Question: Why was the last clause taught?

Suggestion: It teaches about R. Meir's opinion.

Rejection: R. Meir does not distinguish whether Levi was born before or after Yibum. Both cases should have been taught together!

Answer: Rather, it teaches about R. Shimon's opinion.

This shows that R. Shimon argues only when the Yibum preceded the birth, but admits when the birth preceded the Yibum.

(Beraisa): If Shimon was going to give a Ma'amar, and a brother was born before he did, and Shimon died, the first widow is exempt due to Eshes Achiv she'Lo Hayah b'Olamo. The second does Chalitzah or Yibum.

Question: What does it mean- "he was going to give a Ma'amar, but did not"? It matters whether or not he gave it, but not his intent to give it!

Answer: He wanted to give it with her consent, but was not able, and gave it against her will. This is unlike Rebbi:

(Beraisa - Rebbi): A Ma'amar given against the will of the Yevamah is valid;

Chachamim say that it is invalid.

Rebbi learns about Ma'amar from Yibum. Just like Yibum works against her will, also Ma'amar.

Chachamim learn from regular Kidushin, which requires her consent.

Rebbi says that it is better to learn matters of a Yevamah from matters of a Yevamah. Chachamim say that it is better to learn Kidushin from Kidushin.

(Beraisa): If Shimon gave a Ma'amar before or after Levi was born, and died, the first widow is exempt due to Eshes Achiv she'Lo Hayah b'Olamo. The second does Chalitzah, but not Yibum;

R. Shimon says, Yibum or Chalitzah with one woman exempts her Tzarah.

Question: Which case does R. Shimon discuss?

Suggestion: He discusses when the Ma'amar was given after the birth.

Rejection: We proved that R. Shimon admits when the birth precedes Yibum!

Answer: He discusses when the Ma'amar preceded the birth.

(Beraisa): If he does Chalitzah to Ba'alas ha'Ma'amar, her Tzarah is not exempted.

This is because the Tzarah definitely fell to Yibum to Levi, but Ba'alas ha'Ma'amar is Safek (if Ma'amar is not like Yibum, she is Eshes Achiv she'Lo Hayah b'Olamo). A Safek Chalitzah cannot exempt a Vadai Yevamah.

Question (Rav Menasheh bar Zvid): What is R. Shimon's reason?

Objection: The Beraisa explicitly says, because she was permitted from the day he was born!

Correction: Rather, what is Chachamim's reason?

Answer: "u'Lekachah Lo l'Ishah v'Yibmah" - she still is considered a Yevamah from her first husband.