78b----------------------------------------78b

1) IS A MAN BELIEVED TO SAY THAT HIS SON IS A MAMZER?
QUESTION: The Mishnah teaches that a man who says that his son is a Mamzer is not believed. RASHI (DH Eino Ne'eman) explains that the father is not believed because he is a "Karov," a close relative of his son, and the testimony of a relative is not accepted.
Rashi implies that if not for the fact that the father is a relative of his son, he would be believed to testify about his son. Why, though, would he be believed? He is a single witness, and in order to create a Pesul in one's lineage two witnesses are necessary (because "Ein Davar sheb'Ervah Pachos mi'Shenayim," 73b).
ANSWERS:
(a) The RAN disagrees with Rashi and explains that the reason why the father is not believed is that he is a single witness.
(b) The TOSFOS YOM TOV and others explain Rashi's intention as follows. The Mishnah is not discussing a father who wants to disqualify his son who, until now, had a "Chezkas Kashrus" that he is legitimate. If that were the father's intentions, the father certainly would not be believed because he is a single witness and two witnesses are necessary to override a Chazakah. Rather, the Mishnah is discussing an unborn fetus which has no "Chezkas Kashrus" (since it has not been born). In such a case, even a single witness is believed to testify about the status of the child. Rashi understands that the Mishnah's statement includes all cases, and thus he explains that the father is not believed even when the child has no "Chezkas Kashrus" -- because the father is a relative of the child.
The words of the Ran, who explains that the father is not believed because he is a single witness and a single witness is not believed against a Chazakah, imply that if there would be no Chazakah a single witness would be believed. The Ran earlier, however, implies that a single witness is not believed even when no Chazakah counters his testimony. The Gemara earlier (74a) states that three people are believed to testify about the child's status -- the father, the mother, and the midwife. The Ran there asks why a woman's testimony is valid, and he answers that her testimony is valid only mid'Rabanan "because there is no other way" to know the status of the child. The Ran implies that even when no Chazakah is present (such as in the case of a midwife who testifies about the status of the baby just born, before any Chazakah has been established), the midwife is not believed mid'Oraisa. According to the Ran here, however, a single witness should be believed!
The BEIS SHMUEL (EH 4:60) answers that there is a difference between the testimony of a woman and that of an ordinary single witness (Ed Echad). The Ran maintains that although a single witness is believed when there is no Chazakah, he is believed only when he is a valid witness to testify in all other cases in the Torah. Since a woman is not a valid witness for all other cases in the Torah, her testimony cannot be accepted even when no Chazakah is present. (Her testimony is acceptable only for something which eventually will become known, "Milsa d'Avida l'Giluyei.")
2) "MAKNEH DAVAR SHE'LO BA L'OLAM"
QUESTION: Rebbi Yehudah derives from verse of "Yakir" (Devarim 21:17) that a father is believed not only to testify that his son is a Bechor, but also that his son is a Pesul (of impure lineage). The Rabanan disagree and maintain that a father is not believed to testify that his son is a Pesul. What does the verse of "Yakir" teach according to the Rabanan? The Gemara answers that the Rabanan derive from the verse that a father is believed to say that his son is a Bechor when it would not have been known otherwise (i.e. there was no Chazakah that he was the Bechor, such as when he shows up from abroad claiming to be the man's son). Although the father should be believed to say that his son is the Bechor because of a "Migu" that he can give to his son a double portion of his property as a gift, nevertheless the verse "Yakir" is necessary to teach that his testimony that this son is his Bechor is accepted even when he does not presently have the ability to give a double portion of his property to his son, such as when he receives an inheritance after he testifies that this son is his Bechor. In such a case, he has no "Migu" that he could have given the property as a gift to his son, because "Ein Adam Makneh Davar she'Lo Ba l'Olam."
The Gemara explains that according to Rebbi Meir who maintains that "Adam Makneh Davar she'Lo Ba l'Olam" -- a person may transfer ownership of property that has not yet come into his possession (and thus the father still has a "Migu" that he could give his future possessions to this son), the verse is needed to teach that the father is believed to say that his son is the Bechor with regard to property the father will receive as an inheritance when he is a "Goses" (moribund, and no longer able to give a gift to his son).
Why does the father's state of health make a difference once he inherits the property? If a person can make a Kinyan now on a "Davar she'Lo Ba l'Olam" that he will receive only later, his state of health at the moment he receives the item should not matter (as long as he is alive then). He performs the Kinyan now and not later.
ANSWER: The PNEI YEHOSHUA deduces from this Gemara a new understanding of the concept of "Makneh Davar she'Lo Ba l'Olam." Although the person performs the act of Kinyan before the item enters his possession, the actual transfer of ownership occurs only later, at the time the item enters his possession. According to Rebbi Meir, one is able to be "Makneh Davar she'Lo Ba l'Olam" because he obligates himself with "His'chayevus" to be Makneh the item later when he receives it. The act of Kinyan he performs today takes effect only insofar as it makes him obligated to give over the item later. If, later, the Makneh is unable to transfer the ownership of the item (for example, by that time he has become a Goses), the earlier act of the Kinyan itself is unable to effect the transfer of ownership of the item.
3) THE ABILITY TO SPEAK AND THE ACT OF "KINYAN"
QUESTION: The Rabanan disagree with Rebbi Yehudah and maintain that a father is not believed to testify that his son is a Pesul.
According to the Rabanan, what does the verse of "Yakir" teach? The Gemara answers that the Rabanan derive from the verse that a father is believed to say that his son is a Bechor when it would not have been known otherwise (i.e. there was no Chazakah that he was the Bechor, such as when he shows up from abroad claiming to be the man's son). Although the father should be believed to say that his son is the Bechor because of a "Migu" that he can give to his son a double portion of his property as a gift, nevertheless the verse "Yakir" is necessary to teach that his testimony that this son is his Bechor is accepted even when he does not presently have the ability to give a double portion of his property to his son, such as when he receives an inheritance after he testifies that this son is his Bechor. In such a case, he has no "Migu" that he could have given the property as a gift to his son, because "Ein Adam Makneh Davar she'Lo Ba l'Olam."
The Gemara explains that according to Rebbi Meir who maintains that "Adam Makneh Davar she'Lo Ba l'Olam" -- a person may transfer ownership of property that has not yet come into his possession (and thus the father still has a "Migu" that he could give his future possessions to this son), the verse is needed to teach that the father is believed to say that his son is the Bechor with regard to property the father will receive as an inheritance when he is a "Goses" (moribund, and no longer able to give a gift to his son).
TOSFOS explains that a Goses is unable to perform an act of Kinyan because he is unable to speak. Tosfos questions why the Gemara mentions "Goses" as an example of a person who cannot make a Kinyan because he cannot speak. The Gemara should mention an ordinary case of a person who became mute. Tosfos answers that the Gemara does not mention that example because such a person tends to recover from his illness.
Why does Tosfos explain that the reason why a Goses is unable to make a Kinyan is that he is unable to speak? There is a more obvious reason why he cannot make a Kinyan: in his state of "Goses" he does not have the mental capacity (Da'as) to make a Kinyan! Why does Tosfos assume that the ability to speak is so vital to the ability to make a Kinyan? (See KETZOS HA'CHOSHEN 250:8.)
ANSWERS:
(a) The Gemara asks why a special verse is needed to teach that the father is believed; he should be believed to say that a son is the Bechor because he has a "Migu" that he could give a double portion of his property as a gift to that son. Since the father has the power to give his property to his son in practice, Beis Din accepts his word. The GET PASHUT explains that this "power" must be the person's own power in order for the "Migu" to work. If he needs the assistance of others to accomplish the act, the mechanism of "Migu" (or "b'Yado") cannot apply.
A person who cannot speak is unable to state clearly his intention of Kinyan. He may be able to shake his head if asked or try to signal until he is understood, but his intention can be clarified only through the help of others around him. Consequently, the mechanism of "Migu" does not apply to him.
(b) The MAHARIT writes that a person who is unable to speak has a Chazakah that he is not of sound mind and does not have the mental capacity (Da'as) to make a Kinyan. The Maharit maintains that this is the case with any ill person, even one who is not a "Goses." Once a person has lost his power of speech, there is concern that he has lost his Da'as as well and, consequently, he can no longer perform a Kinyan.

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