Besides its value for understanding the text of the Talmud, Nathan’s _Aruk_ has earned other claims to fame. Nathan’s dictionary marks an epoch, says Vogelstein. Consider the situation. The centre of Jewish authority was leaving Babylon. The last of the great literary Geonim--or _Excellencies_, as the heads of the Babylonian schools were called--died in the year 1038. Europe was replacing Asia as the scene of Jewish life. Was the old tradition to die? At the very moment of the crisis, three men arose to prevent the chain snapping. They were almost contemporaries, and their works supplemented each other. There was the Frenchman Rashi--the commentator; the Spaniard al-Fasi--the codifier; and the Italian Nathan--the lexicographer. Between them they re-established in Europe the tradition of the Gaonate. The Babylonian schools might come and go; they might for a time enjoy hegemony, and then fall into decay; but the Torah must go on forever! The manner in which this dictionary carried on the tradition is easily told. Much of the lore it contains, explanations of words and of things, must have been _orally_ acquired in direct conversations with those who were personally linked with the older _régime_. It is again full of quotations of the decisions and customary lore of the Babylonian schools. If on this side the _Aruk_ has almost played out its part for us, it is not because those decisions and customs are less interesting to us than they were to our fathers. But we are now in possession of very many of the gaonic writings in their original. We have recovered several of the sources from which Nathan drew. The Egyptian Genizah--that wonderfully preserved mass of the relics of Hebrew literature--has yielded its richest harvest just in this field. We are getting to know more about the thought and manner of life of the eighth to the eleventh centuries than we know about our own time. But for a long interval men’s knowledge of those centuries was largely derived from the _Aruk_. As a source of information it is not even now superseded. There still remain authors whose names and works would be lost but for Rabbi Nathan’s quotations.