Q&A: A Double Condition
A Double Condition
Question
With God’s help,
I have a question about Rabbi Meir’s view in Kiddushin chapter 3, where he requires a double condition. Rabbi Ovadiah of Bartenura explains there that the basic premise of his view is that we do not say, “from the affirmative you can infer the negative.” Therefore, if I said: “If you cross the Jordan, you will receive the land of Gilead as a possession,” that does not mean that if you do not cross, you will not receive it.
Seemingly, according to the rules of logic, if the condition is not fulfilled then there is also the possibility of carrying out the act and also of not carrying it out, and both situations would be true. The only situation that would lead to falsehood is if the condition is fulfilled and I do not carry out the act that I promised regarding the condition. So why does Rabbi Meir require carrying out the act even when the condition was not fulfilled, if there was no double condition?
Answer
First, see Kovetz Shiurim, Bava Batra 437–438, and in volume 2, section 42, what he cites in the name of Rabbi Chaim of Brisk: that in practice, a double condition is ruled necessary not only because of the reasoning that “from the affirmative you may not infer the negative.”
Second, your question is the question of Tosafot on Ketubot 56a (he asks it even more sharply), and the later authorities already discussed at length the explanation of Rabbi Yehuda’s view there. See Kovetz Shiurim ad loc. and much more.