Bava Batra

a second, the one assigned to her as special surety for her kethubah,  and a third which she had brought him [as marriage] dowry, and for the money value of which he made himself responsible [to her].  Now what property does this exclude from the rule [that the purchase is void]? Shall we say it is to exclude the remainder of the husband's property?  [Hardly]; for in regard to this [she would] certainly [say that she did it to oblige her husband], since otherwise he might, fall out with her and say to her, 'You have your eye on a divorce or on my death.'  The property excluded  must therefore be that of which the husband has the usufruct. But [how can this be], seeing that Amemar has said: If husband and wife sell the property of which he has the usufruct,  their action is null and void?  — Amemar was speaking of the case where the husband sold it and then died, in which case she can recover it,  or where she sold it and died, in which case he can come and recover it,  (according to the regulation of the Sages recorded by R. Jose b. Haninah, who said: It was enacted In Usha  that if a woman sold the property of which the husband had the usufruct and then died, the husband could recover it from the purchaser).  Where, however, they both sold it [together] to a third party or if the wife sold it to the husband, the sale is valid.  Alternatively, I may say that Amemar based his ruling  on the view expressed by R. Eliezer.  For it has been taught: 'If a man sells his slave but stipulates [with the purchaser] that he shall continue to serve him for thirty days, R. Meir says that the rule of "one or two days"15 applies to the first [the original owner] because the slave is still "under" him, and it does not apply to the second because the slave is not "under" him.'  He [R. Meir], holds that possession of the increment is on a par with possession of the principal.  'R. Judah says that the rule of 'one or two days' applies to the second [the purchaser], because the slave is "his money", but not to the first, because he is not "his money".' His opinion is that the possession of the increment  is not on a par with possession of the principal. 'R. Jose says