The Collected Works of Spinoza provides, for the first time in English, a truly satisfactory edition of all of Spinoza's writings, with accurate and readable translations, based on the best critical editions of the original-language texts, done by a scholar who has published extensively on the philosopher's work. This first volume contains Spinoza's single most important work, the Ethics, and four earlier works: the Treatise on the Emendation of the Intellect, the Short Treatise on God, Man, and His Well-Being, Descartes' Principles of Philosophy, and Metaphysical Thoughts. Also included are Spinoza's letters from the periods when these works were being written. The elaborate editorial apparatus--including prefaces, notes, glossary, and indexes--assists the reader in understanding one of the world's most fascinating, but also most difficult, philosophers. Of particular interest is the glossary-index, which provides extensive commentary on Spinoza's technical vocabulary. A milestone of scholarship more than forty-five years in the making, The Collected Works of Spinoza is an essential edition for anyone with a serious interest in Spinoza or the history of philosophy.