This first extensive study of Spinoza's philosophy of mind concentrates on two problems crucial to the philosopher's thoughts on the the requirements for having a thought about a particular object, and the problem of the mind's relation to the body. Della Rocca contends that Spinoza's positions are systematically connected with each other and with a principle at the heart of his metaphysical his denial of causal or explanatory relations between the mental and the physical. In this way, Della Rocca's exploration of these two problems provides a new and illuminating perspective on Spinoza's philosophy as a system .