ENOn a historical plane, the Vilnius thinker's interest in the natural sciences prepared the way for the dissemination of the ideas of the Haskala among the Jews of Lithuania and Byelorussia. It was not by chance that Vilnius became the center of this movement in the mid-19th century. Though personally, the Gaon was undoubtedly a principled opponent of the Enlightenment, which he saw as a direct proponent of dissension against Judaism. His fears had a serious historical foundation: first of all, many of the enlightened Jews of Spain became Christians during the 14th and 15th century; secondly, after the death of Moses Mendelssohn, an ideologue of the Jewish Enlightenment movement in Germany, all of his children became Christians, and a plague of christenings spread among the Jews of Germany in the beginning of the 19th century [p. 74].