Life
Gersonides (1288–1344), known by the acronym Ralbag, was a polymath of southern France — biblical commentator, Talmudist, mathematician, and astronomer who built astronomical instruments and observed the heavens. His major work, The Wars of the Lord (Milhamot HaShem), pressed Aristotelian rationalism further than most dared, on questions of the soul, providence, and creation, sometimes departing from Maimonides. His willingness to follow reason to uncomfortable conclusions made him admired and controversial. He remains a major figure in medieval Jewish philosophy and a notable contributor to medieval astronomy.