Tosfos in Gittin [פ"ג. ד"ה ועמדה] says that if one divorces his wife on condition that she doesn't marry Ploni and she goes ahead and marries Ploni [just to keep things interesting...] - she is not married to Ploni. The rationale is that if we say that she is married then that will mean that she is not married because her original גט will be בטל and she will be married to the first man. A married woman can't get married to a different man.
Then again, once we say that she is not married to Ploni that means that her גט was valid which means that she can now marry Ploni, so the marriage to Ploni is valid. But when we say that her marriage to Ploni is valid then that will mean that her original גט was no good and thus she is still married to her first husband and not to Ploni. But if she isn't married to Ploni then it turns out that her גט IS valid, making her marriage to Ploni valid. But that will mean that her גט is no good and thus her marriage to Ploni is off. No Ploni? Then she is once again divorced making her marriage to Ploni a good one.
AND ROUND AND ROUND.
POOOOOOR PLONNIIIIIIII!!! AZOI FARDREIT [מסובב and dizzy!].
Talk about a COMPLICATED on-off relationship....
But here we have a הכרעה in Tosfos that we DON'T go round and round but that the marriage never gets off the ground [like it seems to happen sometimes when we are stuck in an airplane that won't take off]. The reason is that you can't have a חלות that is סותר itself. Saying she is married means, willy nilly, that she is not married. It never starts.
Rebbe Meir holds [.כתובות נ"ו] that if one married a woman on condition - "על תנאי" in Spanish - that he doesn't have to provide her with שאר כסות ועונה - food, clothing and relations, she is מקודשת and the conditions are cancelled. He explained his reasoning that the rule is that one may not make conditions on Torah law - המתנה על מה שכתוב בתורה תנאו בטל. This implies that if not for that rule the conditions would be in force AND they would be married. How can this be? We find that conditions are effective that if not met, the מעשה upon which they were predicated is invalid. But we find nowhere that the מעשה is valid when the conditions are not met, so what is going on here?!
Rebbe Shimon Shkop ztz"l [the linked sefer written by a friend of mine] explains based on our Tosfos!! If you say that the חיוב of שאר כסות ועונה is in force, that will mean that there is no Kiddushin [because of his תנאי] and thus the חיוב of שאר כסות ועונה is NOT in force. But you can't have a חלות that is סותר itself and that is what would result. So instead, the חיוב of שאר כסות ועונה never starts and they are married. The only thing is that the rule is that if one makes a תנאי to abrogate Torah law, the תנאי doesn't take effect, so his attempt to avoid שאר כסות ועונה was unsuccessful and all he is left with is a wife sans [no relation to Kiryat "Tzanz"] the condition. Pay up or gray up - DUDE!
