Gemara

8b (Beraisa): If a slave brought his Get (document) of freedom, and it says 'all my property is acquired to you', what is the law?

Answer #1 (Abaye): He acquires himself, and along with this, the other property.

Objection (Rava): Granted, he acquires himself, just like a woman is believed to bring her own Get. But he should not acquire the other property without Kiyum (validating the signatures), like the normal law of monetary documents!

Answer #2 (Abaye): Since he does not acquire himself, he does not acquire the other property.

Objection (Rava): Granted, he does not acquire the other property without Kiyum, like the normal law of monetary documents. But he should acquire himself, just like a woman is believed to bring her own Get!

Answer #3 (Rava): Whether it says 'yourself and my property are acquired to you', or 'all my property is acquired to you', the slave goes free, but does not acquire the property.

Question #1 (Rav Ada bar Masnah): You hold like R. Shimon, who says that we split a person's words!

(Mishnah): If a man wrote a document giving all his property to his slave, the slave goes free, but not if the owner kept any property for himself;

R. Shimon says, in every case he goes free, unless it says 'all my property is given to my slave, except for one part in 10,000.'

(Rav Nachman): The Halachah follows R. Meir (Chachamim)!

Question #2: Rav Nachman said that if a Shechiv Mera (one who fears lest he die from his illness) wrote a document giving all his possessions to his slave, and later retracted, he can retract giving the property, but not the freedom. (He contradicts his above ruling like R. Meir, who does not split one's words!)

Answer (to both questions - Rav Ashi): Even R. Meir holds that we split one's words. He holds that if the master retains something in a Get of freedom, it is Pasul. (We learn about freedom from divorce, which requires Sefer Kerisus, totally cutting off.)

Yevamos 47a: A man told R. Yehudah that he converted without Beis Din. He did not have witnesses to prove this.

R. Yehudah: You are believed to disqualify yourself, but not to disqualify your children.

Bava Basra 134b - Question: If one said that he divorced his wife a while ago, (he is not believed regarding the past, but) is he believed regarding the future?

Do we divide his words (and believe that he divorced her, but not when), or not (and since we cannot believe all his words, we do not believe him at all)?

Answer #1 (Rav Mari or Rav Zvid): We divide his words.

Answer #2 (The other of Rav Mari and Rav Zvid): We do not divide his words.

Question: Why is this different than Rava's law?

(Rava): If Reuven says 'Ploni had Bi'ah with my wife', he can join with another witness to kill Ploni, but not to kill his wife. (It is as if he said 'Ploni had Bi'ah with a married woman' and 'a man had Bi'ah with my wife'. He is believed only about the former.)

Answer: When he spoke about two people we divide his words, but not when he spoke about one.

Rishonim

Rif (2a): R. Shimon holds that Palginan Diburei. Even though he cannot clarify (be Mekayem) which property he acquired, we split his words and he acquires himself. The Halachah follows R. Meir. The slave does not go free because this is not Krus Gita, for the document gives rights to the master. A Get of freedom must be entirely for the slave.

Ran (DH v'Salka): Amora'im argue about whether or not we say Palginan Diburei about one Guf. Regarding two Gufim Palginan Diburei, like Rava taught. We say Palginan Diburei regarding what one says about himself, for this is not testimony. One's wife is like oneself, so the same applies to testimony about her. However, what one says about other relatives is Pasul testimony, so we do not say Palginan Diburei. Testimony that is partially Batel is totally Batel. However, here perhaps Palginan Diburei. The Get was signed by Kosher witnesses who are not relatives. He merely verifies that the witnesses are Kosher and removes our suspicions. However, the Yerushalmi equates this to a gift document to two people, and the witnesses are Pasul for (e.g. relatives of) one of them. Reish Lakish said that it is Kosher only for the one for whom the relatives are Kesherim, but we hold like R. Yochanan, who disqualifies the entire document! How can we rule here that Palginan Diburei? Perhaps the Yerushalmi meant that all the more so, Reish Lakish will say Palginan Diburei in our case, but R. Yochanan could distinguish. There, he holds that partially disqualified testimony is totally invalid.

Question: If Reuven says 'I killed Leah's husband', R. Yehudah forbids her to marry, i.e. we do not divide the testimony. But when a man told R. Yehudah that he converted without Beis Din, R. Yehudah divided his words and believed him to disqualify himself, but not his children!

Answer #1 (Rosh Yevamos 4:35): R. Yehudah did not accept his testimony about himself. If the 'convert' has Bi'ah with a Yisraelis, he does not disqualify her. However, he is forbidden to a Yisraelis and does not collect damages (if a Yisrael's ox harmed his ox), due to his admission.

Answer #2 (Tosfos Yevamos 25b DH Leima and Ran Gitin 2b DH v'Salka): What a man says about himself is not testimony.

Teshuvas Rivash (339): If one says something to benefit himself, he is like a relative. It is not testimony at all. We say Palginan Diburei when possible. What one says about himself to his detriment (e.g. his ox must be stoned) is not testimony at all. (There is no need to say Palginan Diburei/)

Poskim

Shulchan Aruch (EH 17:7): If one said 'I killed Leah's husband', she may remarry, for a person cannot establish himself to be a Rasha and Palginan Diburei.

Chelkas Mechokek (16): Some text of the Tur says 'if one of these said, e.g. even a slave (mentioned in Sa'if 5). Our texts say 'If one said'. According to this, perhaps we do not say Palginan Diburei regarding a slave.

Beis Yosef (CM 34 DH v'Chen): The Halachah follows Rava, who is Basra.

Darchei Moshe (CM 34:11): The Mordechai (Yevamos 16) says that we don't split one's words if we must add to them and say that he erred. The Nimukei Yosef and Rashba (1239) say that we do not split one's words if we must say something unusual. (Note: the Nimukei Yosef does not say so explicitly, but Tosfos (Kesuvos 18b DH v'Ein) does - Hagahos Tur ha'Shalem 178.)