Abstract

In Spinoza’s system, the identity of mental modes and extended modes is suggested, but a formal argument for its truth is difficult to extract. One prima facie difficulty for the claim that mental and extended modes are identical is that substitution of co-referential terms in contexts which are specific to thought or extension fails to preserve truth value. Della Rocca has answered this challenge by claiming that Spinoza relies upon referentially opaque contexts. In this essay, I defend this solution by analyzing what is required to establish that Spinoza recognizes referentially opaque contexts as part of his system One objection that has been made to Della Rocca’s account is that he only establishes the intelligibility, not the actuality, of such mode-identity. In this essay, I argue that the intelligibility of mode-identity is sufficient to establish the existence of opaque attribute-specific contexts.