Achronim

Acharonim (Hebrew: [ʔaħaʁoˈnim]; Hebrew: אחרונים ‎ Aḥaronim; sing. אחרון‎, Aḥaron; lit. "last ones") is a term used in Jewish law and history, to signify the leading rabbis and poskim (Jewish legal decisors) living from roughly the 16th century to the present, and more specifically since the writing of the Shulchan Aruch (Hebrew: שׁוּלחָן עָרוּך‎, "Set Table", a code of Jewish law) in 1563 CE.

The Acharonim follow the Rishonim, the "first ones"—the rabbinic scholars between the 11th and the 16th century following the Geonim and preceding the Shulchan Aruch. The publication of the Shulchan Aruch thus marks the transition from the era of Rishonim to that of Acharonim.

The distinction between the "Acharonim", Rishonim and Geonim is meaningful historically. According to the widely held view in Orthodox Judaism, the Acharonim generally cannot dispute the rulings of rabbis of previous eras unless they find supports of other rabbis in previous eras. Yet the opposite view exists as well: In The Principles of Jewish Law Orthodox Rabbi Menachem Elon wrote:

The Principles of Jewish Law

This rule that Menchem Elon cited as originating in the Geonic period did not contradict the precept of Hilkheta Ke-Vatra'ei if understood within the greater context of Torah. While authority may go to the scholars of a later generation within a particular era, the Talmud does not allow scholars of a later era to argue with scholars of an earlier era without support from other scholars of an earlier era. This can be seen when the Talmud asks on numerous occasions how a particular Amora can argue against all the Tannaim without support from any Tanna; the Talmud answers Tanna hu ifalig which means "He is [indeed] a Tanna and he may argue" (Talmud: Shabbat 64b, Eruvin 50b, Taanit 14b, Ktubot 8a, Gittin 38b, Bava Batra 42a). The reason the Talmud initially asked the question is because they lived during the transition between the eras of the Amoraim and the Tanaim and are usually considered Amoraim but may also be considered Tannaim.

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