This chapter investigates Spinoza's conception of reason, focusing on (i) the difference between reason and the imagination, and (ii) the difference between reason and intuitive knowledge. The central interpretive debate this chapter considers is about the scope of rational cognition. Some commentators have argued that it is only possible to have rational cognition of properties that are universally shared, whereas intuitive knowledge may grasp the essences of particular individuals. Another prominent interpretation is that reason differs from intuition only in virtue of its form or manner of apprehension, and not in virtue of the content or ideas it apprehends. However, authors on both sides of the debate have held that reason is incapable of grasping singular things. After summarizing the debate, this chapter presents an argument that Spinozan reason is not blind to particulars: it is (at least sometimes) capable of grasping the causal structure that characterizes an individual.