The position assigned to Saadia in the oldest list of Hebrew grammarians, which is contained in the introduction to Abraham ibn Ezra's "Moznayim," has not been challenged even by the latest historical investigations. Here, too, he was the first; his grammatical work, now lost, gave an inspiration to further studies, which attained their most brilliant and lasting results in Spain, and he created in part the categories and rules along whose lines was developed the grammatical study of the Hebrew language. His dictionary, primitive and merely practical as it was, became the foundation of Hebrew lexicography; and the name "Agron" (literally, "collection"), which he chose and doubtless created, was long used as a designation for Hebrew lexicons, especially by the Karaites. The very categories of rhetoric, as they were found among the Arabs, were first applied by Saadia to the style of the Bible. He was likewise one of the founders of comparative philology, not only through his brief "Book of Seventy Words," already mentioned, but especially through his explanation of the Hebrew vocabulary by the Arabic, particularly in the case of the favorite translation of Biblical words by Arabic terms having the same sound.