Dear Rabbi Kornfeld:
The Gemara brings a beraita: If an ox killes one who is half a slave and half a freeman, the owner gives half the fine to the master and half of the ransom [Kofer] to the heirs. Rava interprets this as "virtual ransom" - it could be paid but is not.
Question: why then does the Tanna state his idea in such a misleading fashion? Why doesn't he just stop at what the Halacha really is, "If an ox killes one who is half a slave and half a freeman, the owner gives half the fine to the master", and refrain from saying anything about what is not paid - or say that it is not paid, instead of saying it is paid? Wouldn't it be better to say that this beraita is a beraita from Beit Hillel before they changed their opinion to say that the master of the half-slave is forced to release the slave in the Mishna, that "If an ox killes one who is half a slave and half a freeman, the owner gives half the fine to the master, and agree that he may not marry, for the reasons enunciated in the Mishna; however: if the half-slave, ON A DAY WHEN HE IS A FREEMAN, cohabits and begets a child from a Kosher Jewish woman outside of wedlock - the child is Kosher and inherits the half-slave? Actually Beit Shammai also could agree to that: they also say that the perosn is a freeman on one day and a slave on others, and the difference between Beit hille and Beit Shammai is only on whether to coerce the Master to release the slave entirely? And they both agree that this half-slave connot marry - but they have NOT said that his child is not considered his. And furthermore - the father may recognize the child as his (Yakir) on a day when he is a freeman, just like on such a day he should keep the Mitzvoth laike a regular Ger Tsedek!?
Can this be refuted? or only argued that "Perhaps the child won't be recognized as the heir of the slave" - to such an answer I would reply: the text of the Beraita supports that there is an heir, just as Rava rejected the previous interpretation of the beraita - of Rav Ada Bar Ahava - on the basis of the text of the beraita!
Yeshayahu HaKohen Hollander
The Rashba indeed says that Rava's answer is simply a "Dichuy," and in general we do say that his Kidushin is a Kidushin. It seems that Rava held that his Kidushin was not a Kidushin, and therefore tried to understand the Beraisa in this light as well (see Chasam Sofer).
All the best,