Gemara

(Mishnah): If Reuven wrote all his property to others, and did not leave any for his sons, it takes effect, but Chachamim are displeased with him.

R. Shimon ben Gamliel says, if his sons were acting improperly, Reuven is praised for this.

(Gemara) Question: Do Chachamim argue with R. Shimon?

Answer #1 (Beraisa): Yosef ben Yo'ezer's son was acting improperly. Yosef had a Keli full of coins; he made it Hekdesh. His son found a pearl. Hekdesh appraised it for 13 Kelim of coins, but Hekdesh had only seven Kelim. The son said 'I will take seven. The other six is my gift to Hekdesh.'

Version #1: They wrote down 'Yosef ben Yo'ezer brought one Keli of coins to Hekdesh, and his son gave six.'

Version #2: They wrote down 'Yosef brought one Keli of coins to Hekdesh, and his son took seven from Hekdesh.' (end of Version #2)

Conclusion: (In Version #1) they wrote that his son also gave to Hekdesh. This shows that they were (also) pleased with Yosef, i.e. Chachamim agree with R. Shimon.

Rejection: In Version #2, they wrote that his son took from Hekdesh. This shows that they were (also) displeased with Yosef, i.e. Chachamim argue!

Conclusion: The two versions contradict one another. We cannot settle our question from here.

Answer #2: Shmuel told Rav Yehudah 'do not be party to transfers of inheritance, even from a bad son to a good son, and all the more so from a son to a daughter! (I.e. Chachamim argue, and Shmuel rules like them.)

(Beraisa): A case occurred in which Reuven's sons were acting improperly. He wrote his property to Yonason ben Uzi'el. Yonason sold a third of it, made a third Hekdesh, and returned a third to Reuven's sons.

Kesuvos 53a: Rav Papa was marrying off his son to Aba Sura'ah's daughter. He went to Aba Sura'ah's house to write the Kesuvah. Yehudah bar Meremar did not want to enter (to pressure Aba Sura'ah to give a big dowry).

Rav Papa: Are you concerned for Shmuel, who said 'do not take part in transferring inheritance, even from a bad son to a good son. Perhaps the bad son will have good offspring!' You hold that all the more so, one should not transfer from a son to a daughter! This is wrong. Chachamim decreed to encourage dowries, like R. Yochanan taught

Rishonim

Rif and Rosh (8:37): The Yerushalmi says about one who writes his property to others "their sins were on themselves."

Hagahos Ashri: All the general rules, e.g. the Halachah follows R. Shimon ben Gamliel in the Mishnah, do not apply when the Gemara explicitly rules otherwise.

Rambam (Hilchos Nachalos 6:11): If Reuven wrote all his property to others, and abandoned his heirs, even if his heirs were treating him improperly, Chachamim are displeased with him. The others acquired what was given to them. It is Midas Chasidus for a Chasid not to testify about a command to transfer inheritance, even from a son acting improperly to his brother, who is a Chacham who acts properly.

Mordechai (625): If one commanded to do with his property 'what is best', we give all of it to his heirs, and not to Tzedakah. We learn from the case of Yosef ben Yo'ezer. It is clear there that he did improperly. We conclude that this is even if one's sons act improperly. The Halachah follows the first Tana. There is no difference between sons and other heirs. Both of them inherit mid'Oraisa!

Gra (CM 282:3): We learn from the case of Yosef ben Yo'ezer that it is improper to give even to Hekdesh.

Note: Our texts say that we cannot answer the question from the case of Yosef ben Yo'ezer. Even though we conclude that Chachamim argue and Shmuel rules like Chachamim, if there is a Hava Amina that Tzedakah or Hekdesh is different, there is no proof from Shmuel!

Rivash (168): In a Teshuvah, Rav Hai Gaon writes 'if one gave all of his property to others, it does not take effect, for he stipulated against the Torah. In Parshas Nachalos, it says "it will be a statute to Yisrael" - it cannot be changed.' I do not understand this. If he commanded that the others will 'inherit', even if he left some for his sons, it does not take effect. If he commanded that the others will get a gift, even if he gave all his property, it takes effect, but Chachamim are displeased. If Rav Hai means that he commanded about a gift, and it takes effect, and if he left some for his sons, Chachamim are not displeased, he should not have attributed the reason to stipulating against the Torah.

Poskim

Shulchan Aruch (CM 282:1): If Reuven wrote all his property to others, and abandoned his heirs, even if his heirs were treating him improperly, Chachamim are displeased with him. The others acquired what was given to them. It is Midas Chasidus not to testify about a command to transfer inheritance, even from a son acting improperly to his brother, who is a Chacham who acts properly.

SMA (1): The Gemara and Tur say 'were acting improperly.' The Shulchan Aruch adopted the Rambam's text, which says 'they were treating him improperly', but they were proper in other matters of Shamayim. Even so, he should not give the money to others.

Tashbatz (3:147, cited in Ketzos ha'Choshen 1): Early documents (to transfer inheritance) leave over four Zuz for the heirs. A Ga'on says that this is so that Chachamim will be pleased, like the Itur explains.

Chasam Sofer (CM Teshuvah 151): This shows that whenever one leaves a proper amount for the heirs, Chachamim are pleased. However, there is no proof from the Itur. The Itur cites the Yerushalmi, in which a man gave his money to R. Aba bar Mamal, and told him to keep half, and to give half to his sons when they will act properly. R. Aba gave half to the sons even though they were not acting properly. They complained about the other half, and he threatened to take back what he gave to them. The Itur says that this refers only to sons, and only if he did not leave anything for them. He may leave for them and also give to poor and rich people. I say that he refers only to the Yerushalmi, which discusses when "their sins were on themselves", which is a great sin, applies. Our Mishnah says only that Chachamim are displeased; this is not such a great sin. R. Aba transgressed the command and gave half to the sons, for he was unwilling to assist the severe transgression of not giving anything to the sons. Even though he kept half, the giver merely displeased Chachamim. A Chasid should not be party to such a command, but the receiver may keep it, for it takes effect. Also Yonason ben Uzi'el returned a third of Reuven's estate to Reuven's sons for this reason. However, Chachamim are displeased whenever any amount is diverted from the sons, and a Chasid should not be party to the command. People without children often command to use their money for good things. One who dies without a son angers Hash-m (116a), so they seek to save themselves from Gehinom. One's own needs come before needs of his heirs. The concern lest his heirs have proper children applies only when one intends to divert from improper children. When the Halachah is shaky, we follow the custom. Perhaps the concern is only for a gift of a Shechiv Mera, which takes effect after death. The property already fell to the heirs, and he seeks to uproot this. A healthy person may give permanent rights to the property from today, and the Peros after death. However, Kesuvos 53a refutes this. I say that one may be party to a command to use much of his money for good things, as long as he left a proper amount for his heirs.

Rema: If one commanded to do with his property 'what is good and proper', we give it to his heirs, for there is nothing better than this.

SMA (4): This is best because the Torah awarded heirs to receive inheritance, and be in place of those who bequeath to them.

Chasam Sofer (CM Teshuvah 151): We learn from Bava Basra that Chachamim are displeased with one who writes is property to others, and even to Hekdesh. We learn from Kesuvos 53a that Chachamim are displeased even if he gives some property to others. (Yehudah did not want to encourage any amount to go to the daughter in place of the sons). Since we are concerned that the bad sons will have proper children, any amount is improper. This applies to all heirs. The SMA (1) cannot discuss one who treated his father improper but was proper in other matters. Mistreating a father is the most blatant Aveirah. It is unreasonable that he transgresses only this! Rather, he discusses other heirs, and one should not assist such a command, even to Hekdesh.