- Question: What is the difference between kilayim (grafting or planting to fruits together of different species) and cooking meat and milk together?
Background:
- Tosfos in Yevamos 83a says that if one runs a grape vine over his friends wheat field, since one cannot forbid(ruin halachically) something which is not his then it is not considered kilayim and everything is permitted. The Talmud Yerushalmi holds his own grapes are forbidden but his friend’s wheat are permitted.
- Rav Elchanan Wasserman asks on this Yerushalmi in his Kovetz Haaros (piece 549) from a case of cooking a non-shechted properly animal (neveila) in milk, where the halacha is the milk is not forbidden for since cooking milk and meat does not apply to a neveila (non-kosher animal) because one prohibition can’t be stacked on a another prohibition, so so to the milk is also not forbidden, for since the prohibition of cooking milk and meat come from both sides combined and one side is not prohibited so the other side is also no prohibited.
- If that is the case that should be true by the forbidden mixture f kilayim, if one is not prohibited the other one should not become prohibited as well, question on the Yerushalmi?!
- Milk and meat create a new entity
- Or (a second answer) there is a difference between the concepts of “no prohibition can stack on another prohibition” vs. “a person can’t forbid something which is not his.”
Answer: . (1) Milk and meat when mixed prohibitively become a new entity so they are either both prohibited as a new entity or both permitted because they never really mixed. (2) Rav Elchanan’s answer was that the axiom “a person can’t forbid something which is not his” (ein adam oser davar she’eino shelo) only applies to his friend but that does not mean his own thing can’t be negatively affected. But the axiom “no prohibition can stack on another prohibition” (ein issur chal al issur) dictates that if the second prohibition can’t go into effect because of the first prohibition then it does go into effect at all, even to affect the milk.