 The commensurability of the motion of heavenly bodies raises an additional concern, having to do with the uniqueness of individual beings and the doctrine of eternal return. Gersonides’ immediate 13th century predecessors Shem-Tov ibn Falaquera and Judah ben Solomon ha-Cohen discussed this issue against the backdrop of Aristotle’s Gen. Animalia. In Gen. Animalia, Aristotle had established a connection between the life spans and gestations periods of animals and the revolutions of the sun and moon (Gen. Anim., IV.10, 777b17–778a10). Thus the revolutions of the sun measure not only time but also produce the alternating periods of growth and decay. Eschatological predictions are thus tied to the cyclicity of the heavenly bodies. Gersonides did not [to our knowledge] indulge in eschatological and millennial predictions. In fact, Gersonides wrote only one astrological text that has survived, a prognostication based on the conjunction of Saturn and Jupiter to take place in March 1345. Gersonides himself died in 1344, a year before the event in question. As Goldstein has demonstrated, this conjunction was predicted already by Ibn Ezra, and repeated by Abraham Bar Hiyya in his Megillat ha-Megalleh where the conjunction was associated with a date of messianic significance that would supposedly take effect in 1358 (Goldstein 1990, p. 3). The conjunction was codified by Levi ben Abraham ben Hayyim in his encyclopedia Livyat Hen, indicating an awareness in the Jewish community of the messianic significance of this conjunction. According to North, Ibn Ezra was the earliest scholar to record one of the seven methods for the setting up of the astrological houses; Gersonides then computed the astrological houses for the prognostication of 1345 according to Ibn Ezra’s method. (See North 1986, p. 25.) Goldstein suggests that as the date 1345 approached, the Papal court might have become interested as well in the conjunction. We do know that Gersonides’ text was translated into Latin with the aid of his brother shortly after Gersonides’ death in 1344.