This A-to-Z reference volume presents definitions, propositions, and explanations of Spinoza’s thought—all in the philosopher’s own words. The seventeenth-century philosopher Baruch Spinoza remains one of the most significant thinkers of our time. Yet his works, written in a rigidly geometric form of argumentation, are notoriously difficult to navigate. Expertly edited by Dagobert D. Runes, Spinoza Dictionary presents an alphabetical selection of Spinoza’s own writings, making essential definitions, concepts, and passages immediately accessible. In his introduction, Runes sheds new light on Spinoza’s private, political, and religious life, and exposes and explains the dramatic story of his apostasy. If the reader despairs of finding his way through Spinoza’s works, here he will find a reliable guide speaking in Spinoza’s own words. “The grand ideas of Spinoza’s Ethics are brought out clearly in this book: not less than the heroic illusions of this great and passionate man.” —Albert Einstein