Tosfos

The Tosafot or Tosafos (Hebrew: תוספות‎) are medieval commentaries on the Talmud. They take the form of critical and explanatory glosses, printed, in almost all Talmud editions, on the outer margin and opposite Rashi's notes.

The authors of the Tosafot are known as Tosafists ("ba'ale ha-tosafot"); for a listing see List of Tosafists.

The word tosafot literally means "additions". The reason for the title is a matter of dispute among modern scholars.

Many of them, including Heinrich Graetz, think the glosses are so-called as additions to Rashi's commentary on the Talmud. In fact, the period of the Tosafot began immediately after Rashi had written his commentary; the first tosafists were Rashi's sons-in-law and grandsons, and the Tosafot consist mainly of strictures on Rashi's commentary.

Others, especially Isaac Hirsch Weiss, object that many tosafot — particularly those of Isaiah di Trani — have no reference to Rashi. Weiss, followed by other scholars, asserts that tosafot means additions to the Talmud, that is to say, they are an extension and development of the Talmud. For just as the Gemara is a critical and analytical commentary on the Mishnah, so are the Tosafot critical and analytical glosses on those two parts of the Talmud. Further, the term tosafot was not applied for the first time to the glosses of Rashi's continuators, but to the Tosefta, the additions to the Mishnah compiled by Judah ha-Nasi I. Tosefta is a Babylonian term, which in Jerusalem writings is replaced by tosafot. The Tosafot resemble the Gemara in other respects also, for just as the latter is the work of different schools carried on through a long period, so the former were written at different times and by different schools, and gathered later into one body.

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