Gersonides (Levi ben Gershom) wrote "The Wars of the Lord," a systematic Aristotelian treatise addressing the immortality of the soul, prophecy, divine knowledge, and creation. He argued controversially that God knows particular contingent events only through their general, lawlike order rather than as individual particulars, a position designed to preserve human free will and the reality of contingency against strict determinism.
Intellectual setting
Gersonides worked as a rigorous Aristotelian within fourteenth-century Provençal Jewish philosophy, and his willingness to follow philosophical argument to controversial conclusions on divine knowledge and the eternity of matter drew sharp criticism from more traditionally minded contemporaries and successors such as Hasdai Crescas.
Key ideas
Qualified divine omniscience
Gersonides argued that God's knowledge extends to the general, ordered structure of nature and possibility rather than to each contingent particular event as such, so that divine foreknowledge does not eliminate genuine human freedom or the openness of the future.
The acquired intellect and personal immortality
Gersonides held that only the intellect actively developed through philosophical and scientific understanding during life becomes capable of surviving death, tying the prospect of personal immortality directly to intellectual achievement.
Legacy
Gersonides is regarded as one of the most philosophically rigorous and independent medieval Jewish Aristotelians, and his astronomical observations and instruments, including the cross-staff he devised for measuring star positions, influenced later medieval and Renaissance astronomy.