An overview of Spinoza'sEhics

Abstract

It is generally acknowledged that the Ethics is Spinoza's greatest work. He is supposed to have completed it in 1675, less than two years before his death in 1677, although early drafts of various parts had been circulating among friends and intellectual peers as early as 1665.1 Spinoza even showed Leibniz the manuscript of his Ethics in 1676 when Leibniz visited him at the Hague.2 Indeed, Leibniz owed a great debt to Spinoza, since in the Ethics we find so many characteristic Leibnizian doctrines, either explicitly or implicitly. For example, one finds an explicit version of the Principle of Sufficient Reason, a special version of the Identity of Indiscernibles (P4, El), a version of the Principle of Plenitude (correspond ing to Leibniz' Principle of Perfection), a distinction between logical and causal necessity, an implicit distinction between finitary versus infinitary analysis, hints of reflection principles, an implicit doctrine of unconscious perception, and hints of a relational view of space and time. All these doctrines were developed to a very great degree by Leibniz, but they can already be found in Spinoza's Ethics, in some form or other. One of the distinctive features of the Ethics is that it is written in the deductive style of Euclidean Geometry. Indeed, Spinoza was quite right to hold that the formal deductive apparatus of Euclidean Geometry could just as well be applied to substances, modes, and attributes as to planes, points, and lines. Thus, Spinoza starts out with axioms, definitions, and postulates, which contain his philosophical terms, and proceeds to deduce propositions, as well as give explanations, all in the manner of Euclid. However, the subject matter of the Ethics has very little to do with Geometry. While Spinoza's deductions are not that rigorous, I have shown in other papers ('A Formalization of Spinoza's Ethics, Part I' and 'Spinoza's Denial of Free Will in Man and God') that they can be formalized according to the standards of mathematical logic, provided that one is willing to supply quite a number of suppressed premises.3 These premises, however, are in no way