"The story of how the gentle but firm Spinoza followed his conscience to the point [of excommunication] has never been better told." —Journal of the American Academy of Religion A forerunner of the Age of Enlightenment, Baruch Spinoza made significant contributions in virtually every area of philosophy, and his writings reveal the influence of such divergent sources as Stoicism, Jewish Rationalism, Machiavelli, Hobbes, Descartes, and a variety of heterodox religious thinkers of his day. Written by German historian Rudolf Kayser, with a foreword by Albert Einstein, this biography reveals the solitude and the struggles of a man who became famous for views that were unusual and widely unknown at that time. Born into a Portuguese Jewish family, he grew up studying Hebrew literature but, dissatisfied with his teachers explanations, sought truth on his own terms. His ideas influenced modern biblical criticism and seventeenth-century rationalism, making him one of the most important philosophers of the early modern period whose impact on later philosophers, including Nietzsche and Hegel, was profound.