Abstract

The thesis explores the philosophical consequences of adopting the view that the principle of non-contradiction, the principle of sufficient reason, and the monistic notion of substance are more closely linked than most modern and contemporary philosophers have supposed. This thesis is then applied to show the connections between the metaphysical views of Spinoza and the view of nature of Albert Einstein. ;The first chapter is an historical overview of the principles of sufficient reason and non-contradiction, and the notion of substance, followed by a presentation of the reasons that led the author to conclude that the usual treatment of these concepts requires revision. These reasons are based upon substantial cause theory, developed in the 1970s by Richard Cole. ;The second and third chapters are an interpretation of Book 1 of Spinoza's Ethics from the viewpoint presented in the first chapter. The implicit role of the principles of non-contradiction and sufficient reason in Spinoza's argument is drawn out through an examination of his definitions, axioms and propositions. ;The third and fourth chapters are an interpretation and criticism of Immanuel Kant. It is first shown that the common dismissal of Kant's philosophy based upon the discovery of non-Euclidean geometries and the denial of strict causality among some physical events is not well founded; ways in which Kant's framework can accommodate these problems are proposed. It is then argued that Kant's criticism of traditional metaphysics is not conclusive. In particular, Kant's arguments against the possibility of an ontological argument are examined and criticisms of his arguments are presented. ;The sixth and seventh chapters contain an historical account of the development of physics in the 20th century to illustrate the strong tendency toward unification found in science. It is suggested that this natural tendency to seek ever higher levels of unification is evidence that the principle of sufficient reason plays a role in the development of physical theory, although usually not a self-conscious one. ;The eighth chapter concludes the work with a discussion of the relation of Spinoza and Einstein. Some ways are presented in which Spinoza's monistic view of Nature may be understood in light of modern physical theory.