David Friesenhausen

David ben Meir Cohen Friesenhausen (1756 to 1828) was a German-Hungarian astronomer, maskil, mathematician and rabbi, born in Friesenhausen in southern Germany. After thirty years of exclusive Torah study he took up mathematics, astronomy and philosophy, and in Berlin in 1796 he published Kelil Heshbon, a Hebrew manual on algebra and trigonometry. His book Mosedot Tebel supported Copernican heliocentrism, making him one of the first Jews to do so. He lived later in Huncovce and then Pest, and proposed that rabbinical candidates follow a dual curriculum of Jewish and secular studies in government-overseen seminaries, an early expression of Torah im Derech Eretz. The Hungarian rabbinate opposed him, and the government declined the plan in 1813.