In this paper I attempt to reconstruct the outline of Spinoza’s mereology. Doubtlessly, I will not be able to provide here a full and comprehensive account, but I do hope to make some significant headway toward the development of such an account. In the first part of this paper, I will begin with a preliminary exploration of Spinoza’s understanding of part and whole and attempt to explain Spinoza’s claim that certain things are indivisible. In the second part, I will study and explain Spinoza’s view on the priority of parts to their wholes, and point out the contrast between the whole-part and substance-mode relationships in Spinoza. In the third part I will investigate the termini of Spinoza’s mereology: the largest wholes and the smallest parts (if there are any). In the fourth part, I will attempt to explain and motivate Spinoza’s claim that mereology cuts across the attributes, i.e., the fact that the parallelism among the attributes preserves the same mereological relations. In order to motivate this claim we will have to clarify the relationship between mereology and causation in Spinoza, and explain his notion of “singular things.”
