Spinoza's Theory Of Substance Monism

In Part One of The Ethics, Spinoza establishes his substance monism and proves that God, as an infinite being, is the sole substance in the universe. The task that follows in Part Two is to explicate the character of everything else which flows from the nature of God. In Proposition 7, he outlines what has since been termed the “parallelism” doctrine (Heide 02 Mar). He faces the challenge of explaining why why ideas and bodies appear to be so consistently coordinated, given that they are modes of the distinct attributes of thought and extension respectively. They have nothing in common and, therefore, have no causal interaction with one another (Pr.3,I). According to his parallelism, ideas and bodies are merely two different expressions of the same substance, God, each reflecting God 's nature through its proper attribute. The argument for this position relies on Spinoza 's conception of substance, on his account of attributes, on his theory of causation, and, finally, on how the term “infinite” ought to be …show more content…
Attributes have nothing in common with each other, a feature which also prevents them from causally impacting one another. Attributes are metaphysically secondary to substance, and are just different ways by which “the intellect perceives” the essence of substance (Def.4,I). There is one substance which is self-caused through its own essence, and that is God. Consequently, Spinoza must be committed to there being two separate causal explanations for the universe because, otherwise, it would be true that an idea could be understood through extension and by reference to bodies, which is incoherent. There is nothing in thought, or its manifestation as ideas, which contains any content that can also be found in extended bodies. Similarly, it makes no sense to speak of a body in terms of ideas and thought, which by definition must exclude