Spinoza and the metaphysics of mechanism

Thaddeus Steven Robinson, Purdue University

Abstract

Descartes, Gassendi, Galileo, Boyle, Spinoza, and Hobbes, among many others, were adherents of what Boyle called "the mechanical philosophy". According to the mechanical philosophy, the explanation for all natural phenomena is found in the various motions and collisions of insensible particles of matter. The first half of the 17th Century saw a number of efforts to systematize the mechanical philosophy by providing it with a solid metaphysical foundation. In his Principles of Philosophy Descartes put forth perhaps the most successful and influential of these early efforts. Spinoza, like many of his contemporaries, was impressed with Descartes' system; nevertheless, he was convinced of the inadequacy of the underlying metaphysics. The basic tools of mechanistic explanation are matter and motion, and any attempt to systematize the mechanical philosophy must offer accounts of each of these tools. It was with Descartes' account of precisely these tools that Spinoza took issue. In my dissertation I argue that much of what is distinctive about Spinoza's metaphysics arose, at least partially, as the result of Spinoza's efforts to replace Descartes' suspect metaphysics of matter and the relation between matter and motion, with philosophically adequate accounts. I begin in chapter one by offering a characterization of 17th Century mechanism in general. I then turn to Descartes' specific interpretation of mechanism and metaphysics which underlie it by taking a close look at the first two books of Descartes' Principles of Philosophy. Last, I show Spinoza's commitment to Descartes' account of mechanism. In chapter two I present and critically evaluate Spinoza's criticisms of Descartes' account of matter. I show that Spinoza offers two arguments for the conclusion that Descartes' account can't be right, and that the lesson he draws is that no corporeal substance is (i) composed of really distinct parts, (ii) a body, despite the fact that it is extended and (iii) as such, Descartes is wrong to think that the essence of body is extension. In chapter three I argue that these considerations lead Spinoza to maintain that regions of extension, as opposed to bodies, are the subjects of motion and that the essence of body is extension in motion. I make this case by offering a novel interpretation of what Spinoza refers to as "the immediate infinite mode of extension". Perhaps the chief obstacle to understanding Spinoza's substance monism is accounting for the relation between bodies and the one extended substance. I argue in chapter four that Spinoza avoids the problems with Descartes' account of matter by adopting the Scholastic-Aristotelian idea of a posterior part to account for the relation between bodies and extension. In the final chapter I turn to Spinoza's resolution of the tension between mechanical and theological explanation. The explanations the mechanical philosophy seeks to offer take the form of showing that any particular observable phenomenon is the effect of a series of causal relations obtaining between particles of matter. However, on its face, this view conflicts with the traditional theological commitment that God is the sole cause and author of all things, a view to which Spinoza adheres. In chapter five, I argue that Spinoza is a concurrentist, and as a result resolves this problem by maintaining that instances of secondary causation are instances in which God and finite modes concur in causing an effect. In making this case I outline Spinoza's unique account of force and show how, according to Spinoza, it grounds the laws of nature.

Degree

Ph.D.

Advisors

Cover, Purdue University.

Subject Area

Philosophy

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