Answer #1: Abaye learned from the following.

(Rav Chiya bar Ami - Beraisa): If an Arusah (a wife during Eirusin, i.e. engagement) dies, her husband does not become an Onen (a mourner before the burial) and does not become Tamei to engage in her burial. If he dies, she does not become an Onen or become Tamei for him. If she dies, he does not inherit her. If he dies, she collects her Kesuvah.

Rejection: Perhaps that is when he wrote her a Kesuvah!

Question: If so, this is obvious!

Answer: (Indeed, it is.) It was taught along with 'when she dies, he does not inherit her', which was not obvious.

Answer #2: Abaye had no source that a widow from Kidushin gets a Kesuvah. He retracted due to the Mishnah itself.

If the Mishnah is in a place where people do not write Kesuvos, the Get is the Kesuvah, and it does not say that she collects 100 or 200!

Suggestion: Perhaps since Chachamim enacted 100 or 200, it is as if this is written in the Get!

Rejection: If so, he could claim that he paid her!

Suggestion: Perhaps that is no claim, for then he should have torn the Get (to stop her from collecting again).

Rejection: He cannot tear it, for she needs it to remarry!

Suggestion: Beis Din should have torn the Get, and written that the tear just shows that the Kesuvah was paid, but not that the Get is invalid!

Rejection: He can say that he paid her outside of Beis Din (therefore, it is not torn)!

(Mishnah): If one finds a Get of divorce or freedom, or a document of a gift or a receipt, he does not return it. Perhaps the giver reconsidered and never gave it.

(Gemara) Inference: The only concern is that he reconsidered. If he would say to give it, we would give it, even if it was found much later!

Contradiction (Mishnah): If one brought a Get and lost it, if he found it immediately, it is Kosher. If not, it is invalid.

Answer #1 (Rabah): If it was lost in a place through which caravans pass, it is only valid if it was found immediately. If caravans do not pass through, it is Kosher even if it was found later.

Even where caravans pass, it is invalid (if found later) only if we know that another couple in the city have the same names as on this Get. If we do not know, it is Kosher.

If we would not say this, Rabah would contradict himself.

A Get was found in Rav Huna's Beis Din. It said 'in the city of Sheviri, on the Rachis River.'

Question (Rav Huna): Are we concerned lest there are two cities 'Sheviri' on the Rachis River (and this Get belongs to a man of the other city, so we do not return it)?

Answer (Rabah - Mishnah): We return any document of actions of Beis Din.

Even though Rav Huna's Beis Din is (frequented by many people) like a place where caravans pass, Rabah ruled that we return it!

We must say that if we do not know that two couples have the same names (or that there is another city with the same name), we are not concerned.

Rabah ruled like this about a document found in the flax district of Pumbedisa.

Version #1: It was where flax is sold. Caravans pass there. He returned it because we did not know about someone else with the same name.

Version #2: It was where flax is soaked. He returned it even though there was someone else with the same name, because caravans do not pass there. (end of Version #2)

Question (R. Zeira - Mishnah): One who brings a Get and lost it, if he found it immediately, it is Kosher. If not, it is invalid.

Contradiction (Beraisa): If a Get was found in the market, if the husband says to give it, we give it to his wife. If not, we do not return it to either of them.

Inference: When the husband agrees, we give it to her, even if it was found long after it was dropped!

Answer #1 (R. Zeira): If it was lost in a place through which caravans pass, it is valid only if it was found immediately. If caravans do not pass through, it is Kosher even if it was found later.

Version #1: Even where caravans pass, we are concerned only if we know of someone else with the same name. This is like Rabah.

Version #2: Where caravans pass, we are concerned even if we do not know of someone else with the same name. R. Zeira argues with Rabah. (end of Version #2)

Rabah did not ask like R. Zeira, for it is better to ask a contradiction between Mishnayos.

Question: Why did R. Zeira prefer to ask the contradiction between the Mishnah and Beraisa?

Answer: Our Mishnah does not explicitly discuss returning it to her. We only inferred that we return it to her when he agrees. Perhaps this is only if it was found immediately. (However, the Beraisa explicitly discusses returning it to her. If this were only immediately, it would have said so.)

Question: According to Version #2, where caravans pass, R. Zeira is concerned even if we do not know of someone else with the same name. What do he and Rabah argue about?

Answer: Rabah explains that in the Mishnah 'all actions of Beis Din, we return them' implies that it was found in Beis Din, which is like a place where caravans pass;

We must say that only when we know of someone else with the same name, we do not return;

R. Zeira disagrees. The Mishnah does not say that they were found in Beis Din. They were found outside (which is not like a place where caravans pass).

Answer #2 (to contradictions 2:c and 2:f - R. Yirmiyah): The Mishnah permits returning a Get when the witnesses say that they only signed on one Get for a man of this name.

Question: Obviously, we may return such a Get!

Answer: One might have thought that we should be concerned lest other witnesses with the same names as these witnesses signed a Get for another couple with the same names. He teaches that we are not concerned.

Answer #3 (Rav Ashi): The Mishnah permits returning a Get when the loser tells us (a superb Siman (sign that it is his), such as) a hole in the Get next to a particular letter.

This is only if he says which letter the hole is near. If he says only that there is a hole, we do not return it.

Rav Ashi is unsure whether the Torah allows returning lost objects when the loser gives a mediocre Siman. (If so, this suffices also for a Get.) Or, perhaps this is only a Rabbinical enactment (regarding money, but for a Get we require a superb Siman. Due to his doubt, he requires a superb Siman.)