<div dir="ltr"><div>There's alot to say about how to reconcile the Rambam with the Gedolei Haposkim, but in summary:</div>
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<div>1) The level of knowledge today suffices to judge them as Mezidim (Radvaz (they have been *warned* to return to Torah,not just heard about it); Mabit (I:37 - Once they have received reproof and not returned they are like their fathers, and "they know that they come from Jewish seed and that their fathers have denied the Oral Law", Maharikash (33,34 - they are *like* Anussim after they have heard the truth - not really Anussim. Therefore don't *rush* to kill them since they might do Teshuvah).</div>
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<div>2) Rambam is only talking about not rushing to kill them, but regarding other Halachos they are like gentiles (Radvaz, Mabit, Maharikash, Ginas Veradim (II:31).</div>
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<div>3) [Limited applicability] Denigration of the Chachmei Hador makes them Mezidim, and makes it unlikely for them to do Teshuvah (Re'em (57); Ginas Veradim, Maharash Vital (Be'er Mayim Chayim 41). They also cause other Jews to follow them because of this (Rambam Perush Hamishnah Chullin 1).</div>
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<div>The Chazon Ish himself writes that the Machlokes Acharonim is on the issue of "the level of knowledge, to what extent to they know of the existence of the Jews, and that their fathers separated from them and turn their shoulder." He also writes that the reason why the Tinokos Shenishbu are treated as Jews is because they have a Chazakah that they will repent if told sufficiently. While among the Chilonim today there are Chozrim B'Teshuvah, it is difficult to say that they have a Chazakah of doing Teshuvah, see Ginas Veradim there. The CI forbade foods cooked in factories by non-Torah observant Jews, and RYSE says that we see that L'chumrah the CI did not think they had a Din of TNS.</div>
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