The Guide for the Perplexed

According to Wikipedia, ""The Guide for the Perplexed is one of the major works of Rabbi Moshe ben Maimon, better known as Maimonides or "the Rambam". It was written in the 12th century in the form of a three-volume letter to his student, Rabbi Joseph ben Judah of Ceuta, the son of Rabbi Judah, and is the main source of the Rambam's philosophical views, as opposed to his opinions on Jewish law... ...