Ketubot

In the name of R. Eliezer,  however, it was stated: She  must perform halizah but may not contract the levirate marriage.  Now, here,  surely, it is a case similar to that of an error  affecting merely one woman and they  nevertheless differ!  — In that case  also [it may be said that]  they  differ on the following principles.  One Master  maintains that everyone is aware that there is no validity in the betrothal of a minor and, consequently, any man having intercourse [after such an invalid act] determines that his intercourse shall serve the purpose of a betrothal.  The other Master,  however, maintains that not everyone is aware that there is no validity in the betrothal of a minor, and when a man has intercourse [after such an act  he does so] in reliance on his original betrothal. [So]  it was also stated: R. Aha b. Jacob stated in the name of R. Johanan. If a man betrothed a woman on a certain condition and then had intercourse with her, she,  it is the opinion of all, requires no letter of divorce from him. R. Aha the son of R. Ika, his  sister's son  raised an objection against him: A halizah under a false pretext  is valid; and what is 'a halizah under a false pretext'? Resh Lakish explained: Where a levir is told, 'Submit to her halizah and you will thereby wed her'. Said R. Johanan to him:  I am in the habit of repeating [a Baraitha,] 'Whether he  had the intention  [of performing the commandment of halizah] and she had no such intention, or whether she had such intention and he had not, her halizah is invalid, it being necessary  that both shall [at the same time] have such intention', and you say that her halizah is valid?  But, said R. Johanan, [this is the meaning:]  When a levir is told, 'Submit to her halizah on the con dition that she gives you two hundred zuz'.  Thus  it clearly follows that as soon as a man has performed an act  he has thereby dispensed with his condition, [why then should it not be said] here also that as soon as the man has intercourse he has thereby dispensed with his condition?  — The other replied: Young hopeful,  do you speak sensibly?  Consider: Whence do we derive [the law of the validity of] any condition? [Obviously] from the condition in respect of the sons of Gad and the sons of Reuben;  [hence it is only] a condition that may be carried out through an agent, as was the case there,  that is regarded as a valid condition; but one which cannot be carried out through an agent,  as was the case there, is not regarded as a valid condition.  But is not intercourse  an act which cannot be performed through an agent as was the case there  and yet a condition in connection with it is valid?  — The reason  there is because the various forms of betrothal  were compared to one another. R. 'Ulla b. Abba in the name of 'Ulla in the name of R. Eleazar stated: If a man betrothed a woman by a loan  and then had intercourse with her, or on a certain condition  and then had intercourse with her, or with less than the value of a perutah  and then had intercourse with her, she,  it is the opinion of all, requires from him a letter of divorce. R. Joseph b. Abba, in the name of R. Menahem in the name of R. Ammi stated: If a man betrothed a woman with something worth less than a perutah and then had intercourse with her, she  requires a letter of divorce from him.  It is only in this case  that no one could be mistaken,  but in the case of the others  a man may be mistaken. R. Kahana stated in the name of 'Ulla: If a man betrothed a woman on a certain condition  and then had intercourse with her, she  requires a divorce from him.  Such a case once occurred and the Sages could find no legal ground  for releasing the woman without a letter of divorce. [This is meant] to exclude [the ruling] of the following Tanna. For Rab Judah stated in the name of Samuel in the name of R. Ishmael: And she be not seized  [only then  is she] forbidden;  if, however, she was seized  she is permitted.  There is, however, another [kind of woman] who is permitted  even though she was not seized.  And who is she? A woman whose betrothal was a mistaken one  and who may, even if her son sits riding on her shoulder,