abstract:Levi ben Gershon (1288–1344), better known by his Latinised name as Gersonides or the abbreviation of first letters as RaLBaG,"Ralbag" is the acronym of "Rabbi Levi Ben Gershon", with vowels added to make it easily pronouncable - the normal traditional Jewish practice with the names of prominent Rabbis. was a philosopher, Talmudist, mathematician and astronomer/astrologer.