Resources for Yevamos daf 82
1. The גמרא says that ר׳ יהודה holds מין במינו is not בטל. תוספות in ד"ה רבי יהודה says that רבי יהודה only says מין במינו is not בטל by a mixture of two liquids. He would agree that when solids are mixed that we would say it is בטל ברוב. רש"י on the previous עמוד in ד"ה ר׳ יהודה where the גמרא is discussing the pieces of חטאת meat that got mixed together says that the reason ר׳ יהודה says it isn’t בטל is because מין במינו אינו בטל. It is clear that רש"י disagrees with תוספות and holds that ר׳ יהודה‘s דין of מין במינו אינו בטל applies to solid dry items as well (תוספות there learns the גמרא to be talking about דרכו לימנות and not מין במינו). The way תוספות explains his שיטה is that לח בלח is harder to be מבטל because the איסור spreads all over, as opposed to dry items where the איסור and היתר remain separate. In קובץ הערות in סימן ס׳ אות ה, רב אלחנן זצ"ל explains that ביטול by dry items works completely differently than by liquid items. By dry items, the איסור is מתבטל בתוך הרוב which means the איסור doesn’t lose it’s identity but is nonetheless בטל in the mixture. So for example if you carried a piece of נבילה meat (which is מטמא במשא) that was mixed with a majority of Kosher meat, even though it would be מותר to eat since it is בטל ברוב, you would still be טמא since you carried the whole bag and the נבילה still exists. Nonetheless, there is no reason in this case to say there is a difference between מינו and אינו מינו. Conversely, when liquids mix, the איסור is מתבטל לגבי הרוב which means that the איסור becomes one with the larger היתר and completely loses it’s identity. Therefore, even if you carried it all in one bag you wouldn’t be טמא. On the other hand, ר׳ יהודה would insist that מין במינו wouldn’t be בטל because you can’t lose your identity to yourself. You are still you and if water mixes with water it is still water.
2. The גמרא mentions דבר שיש לו מתירין. There is a מחלוקת הראשונים how to understand דבר שיש לו מתירין and one of them would seem to be difficult based on our גמרא. רש"י in ביצה דף ג' ע"ב ד"ה יש לה מתירין says that the reason חז"ל said that a דבר שיש לו מתירין is not בטל is because “why eat it when it’s אסור” if you can just wait a week and it will be מותר (this actually sound similar to רש"י’s שיטה here of ביטול only being a בדיעבד). The ר"ן in נדרים דף נ"ב says a completely different idea. He says that for ביטול to work we require a clash of some kind like איסור והיתר. This is why ר׳ יהודה holds here that מין במינו אינו בטל—there is no clash since they are the same מין. The חכמים hold that since they are halachically different in that one is איסור and one is היתר then there is a clash. However, by a דבר שיש לו מתירין which is also מין במינו even the חכמים would agree that there is no clash since even the איסור will soon be היתר. A third understanding of דבר שיש לו מתירין that we learn from inference is the רי"ף in פּרק גיד הנשה which is brought by the ר"ן and other ראשונים. The רי"ף says that meat baked in the same oven as bread should not be eaten with milk since it’s a דבר שיש לו מתירין. The רי"ף seems to learn that דבר שיש לו מתירין means anything where a היתר way to eat it exists, even if there are many ways which will never become מותר. The ר"ן asks that this seems to be against our גמרא since our גמרא says that if the חטאת meat will never be permissible to a ישראל, the fact that there is a person who could eat it (i.e. the כהן) does not make it a דבר שיש לו מתירין. He answers that there is a difference between two people and one person who has two ways to eat something. We won’t be מחמיר on the ישראל just because there is someone else who could eat it, but we will be מחמיר on someone of there is another way he could eat it.
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