Maimonides' Guide to the Perplexed is a classic of world philosophy. Written in Arabic and completed around 1190, the work is among the most powerful and influential living texts in Jewish philosophy, a masterwork navigating the straits between religion and science, logic and revelation. The author, Rabbi Moses ben Maimon, commonly known as Maimonides or as Rambam, was a Sephardi Jewish philosopher, jurist, and physician. He wrote his Guide in the form of a letter to a disciple. But the perplexity it aimed to cure might strike anyone who sought to square logic, mathematics, and the sciences with biblical and rabbinic traditions. In this new translation by philosopher Lenn E. Goodman and historian Phillip I. Lieberman, Maimonides' warm, conversational voice and clear explanatory language come through as never before in English. Maimonides knew well the challenges facing serious inquirers at the confluence of the two great streams of thought and learning that Arabic writers labeled 'aql and naql, reason and tradition. The aim of the Guide, he wrote, is to probe the mysteries of physics and metaphysics. But mysteries, to Maimonides, were not conundrums to be celebrated for their obscurity. They were problems to be solved. Maimonides' methods and insights resonate throughout the work of later Jewish thinkers, rationalists, and mystics, and in the work of philosophers like Thomas Aquinas, Spinoza, Leibniz, and Newton. The Guide continues to inspire inquiry, discovery, and vigorous debate among philosophers, theologians, and lay readers today. Goodman and Lieberman's extensive and detailed commentary provides readers with historical context and philosophical enlightenment, giving generous access to the nuances, complexities, and profundities of what is widely agreed to be the most significant textual monument of medieval Jewish thought, a work that still offers a key to those who hope to harmonize religious commitments and scientific understanding.