This volume unites Peter Winch's previously unpublished work on Baruch de Spinoza. The primary source for the text is a series of seminars on Spinoza that Winch gave, first at the University of Swansea in 1982 and then at King's College London in 1989. What emerges is an original interpretation of Spinoza's work that demonstrates his continued relevance to contemporary issues in metaphysics, epistemology and ethics, and establishes connections to other philosophers - not only Spinoza's predecessors such as Ren Descartes, but also important 20th Century philosophers such as Ludwig Wittgenstein and Simone Weil. Alongside Winch's lectures, the volume contains an interpretive essay by David Cockburn, and an introduction by the editors.