Spinoza's causal axiom is at the foundation of the Ethics. I motivate, develop and defend a new interpretation that I call the ‘causally restricted interpretation’. This interpretation solves several longstanding puzzles and helps us better understand Spinoza's arguments for some of his most famous doctrines, including his parallelism doctrine and his theory of sense perception. It also undermines a widespread view about the relationship between the three fundamental, undefined notions in Spinoza's metaphysics: causation, conception and inherence.

I defend a new reading of Spinoza's account of causation that reconciles the strengths of the mechanist and formal cause interpretations by locating instances of nature's fixed and unchanging laws inside individual natures; natures are efficacious because that's where the laws are. God's necessity, for instance, follows from certain logical principles contained within God's nature. Causes between finite particulars likewise stem entirely from finite natures. They do so, I argue, because finite instances of nature's fixed and unchanging laws are inscribed (...) within those natures. In each of these instances, effects follow from natures on account of laws contained within them. (shrink)

Commentators standardly ascribe to Spinoza a belief in an exceptionless conceptual closure of mental and physical realms: no intention can allow us to understand a bodily movement, no bodily injury can make intelligible a sensation of pain. This counterintuitive doctrine, most often now referred to as Spinoza's 'attribute barrier', has weighty repercussions for his views on intelligibility, nature of the mind, identity, and causality. I argue against the standard reading of the doctrine, by showing that it produces an inconsistent epistemological (...) picture, contradicting Spinoza's theory of mind and his commitment to universal intelligibility. The alternative account I propose is also philosophically more compelling and plausible as an account of thought in its essential intentionality. (shrink)