Yakov,

[1] QUESTION: Please excuse me for the delay in my reply. From what you write, I understand that your question is the following. Why, when a person that is Chayav Sereifah is mixed with many people that are Chaya Sekilah, should Tosfos suggest that they all are Chayav Sekilah because of Rov. A person is a living creature, and a living creature is not Batel b'Rov! (Zevachim 73a) All of the people should now be Chayav Sereifah, like the minority dictates!

Your question is excellent. In fact, rather than being a question on the Oneg YomTov, it is a question on TOSFOS Chullin 11b DH Lachush (who applies the laws of Rov to the person who is mixed with Chayvei Sekilah) as well -- when Tosfos is looking for a reason to exempt the person who is Chayav Sereifah from the laws of Rov, he should have mentioned your reason! In fact, the Gemara itself applies the laws of Rov to this situation (Sanhedrin 80b, "ve'Teipuk Lei d'Nisrafin *Ruba*"), so your question may be asked on the Gemara too. Why should the laws of Rov apply here?

[2] ANSWER: The answer, I believe, lies in the very point of Tosfos that you mentioned in your question. In Tosfos' second answer, he explains that the laws of Rov do not apply to this case because the person who is Chayav Sereifah is "Kavua." Does Tosfos mean to say that whenever an object is mixed into a larger group we do not apply the laws of Rov, since the object is "Kavua?" When, then, *do* we apply the laws of Bitul b'Rov! Isn't every Bitul b'Rov exactly such a situation? (The KREISI, Yoreh Deah 10:12, raises this question and disagrees with Tosfos.)

I think it is clear that Tosfos is using Kavua in the context of the Gemara in Zevachim 73b, where it is used when a living creature that is Asur for Korbanos is mixed with creatures that are Kosher for Korbanos. Tosfos (72b) explains that this is not a true example of Kavua; the Gemara really means that Ba'alei Chayim are not Batel (as it says on 73a) mid'Rabbannan, and this is what it refers to as Kavua. This, then, is Tosfos intention here as well. Tosfos means to suggest just what you yourself suggested -- the Chayav Sereifah is not Batel since he is a living creature, making the situation one of Kavua!

[3] QUESTION: If anything, your question can be asked in the following manner: Why did Tosfos find it necessary to suggest *another* answer to his question -- what is wrong with the clear and obvious answer that you suggested, and that Tosfos used in his second answer? The answer to that is that the Gemara in Sanhedrin explicitly applies the laws of Rov to the case in question; we cannot say that the laws of Rov do not apply there for the reason you suggested. (In Tosfos' second answer, he finds a somewhat forced way out of this question, see Tosfos.) But your question can now be transferred the Gemara itself. Why did the *Gemara* assume that the laws of Rov apply to this case?

[4] ANSWER: The answer is that in the case in question, where a Chayav Sereifah is mixed with Chayvei Sekilah who are a Rov, if the Rabbanan apply the rule that living creatures are not Batel it will cause the *Kula* of exempting the Chayav Sereifah from being killed with Sekilah, as the Rov dictates. The Rabbanan only applied their rule that living creatures are ont Batel when not-being-Batel causes a *Chumra,* not where it causes a Kula. (I implied this from the wording of Tosfos' second answer here and in Sanhedrin.)

I hope that you find this helpful. Be well,

-Mordecai