The foundations of this process of analysis were laid by Abba Arika (175–247), a disciple of Judah ha-Nasi. Tradition ascribes the compilation of the Babylonian Talmud in its present form to two Babylonian sages, Rav Ashi and Ravina II. Rav Ashi was president of the Sura Academy from 375 to 427. The work begun by Rav Ashi was completed by Ravina, who is traditionally regarded as the final Amoraic expounder. Accordingly, traditionalists argue that Ravina's death in 475 is the latest possible date for the completion of the redaction of the Talmud. However, even on the most traditional view, a few passages are regarded as the work of a group of rabbis who edited the Talmud after the end of the Amoraic period, known as the Savoraim or Rabbanan Savora'e (meaning "reasoners" or "considerers"). Comparison of style and subject matter There are significant differences between the two Talmud compilations. The language of the Jerusalem Talmud is a western Aramaic dialect, which differs from the form of Aramaic in the Babylonian Talmud. The Talmud Yerushalmi is often fragmentary and difficult to read, even for experienced Talmudists. The redaction of the Talmud Bavli, on the other hand, is more careful and precise. The law as laid down in the two compilations is basically similar, except in emphasis and in minor details. The Jerusalem Talmud has not received much attention from commentators, and such traditional commentaries as exist are mostly concerned with comparing its teachings to those of the Talmud Bavli. Neither the Jerusalem nor the Babylonian Talmud covers the entire Mishnah: for example, a Babylonian Gemara exists only for 37 out of the 63 tractates of the Mishnah. In particular: The Jerusalem Talmud covers all the tractates of Zeraim, while the Babylonian Talmud covers only tractate Berachot. The reason might be that most laws from the Order Zeraim (agricultural laws limited to the Land of Israel) had little practical relevance in Babylonia and were therefore not included. The Jerusalem Talmud has a greater focus on the Land of Israel and the Torah's agricultural laws pertaining to the land because it was written in the Land of Israel where the laws applied. The Jerusalem Talmud does not cover the Mishnaic order of Kodashim, which deals with sacrificial rites and laws pertaining to the Temple, while the Babylonian Talmud does cover it. It is not clear why this is, as the laws were not