While the notion of freedom plays a central role in Spinoza's philosophy, it is far from obvious how he understands it. A first interpretive difficulty is understanding the unity of Spinoza's claims about freedom. Whereas Part i of the Ethics defines freedom in metaphysical terms as being the cause of one's own existence and actions, the later text treats freedom as equivalent to the ethical goal of mastering one's emotions. But it is not clear how mastering the emotions involves being free in the sense of self-caused. A second difficulty is understanding the consistency of Spinoza's claims about freedom. Defining freedom as self-caused implies that only God can be free, a conclusion Spinoza openly accepts. On the other hand, since his ethics promises to help us attain freedom, without giving any indication that this is an unrealistic goal, he also seems to hold that we can attain freedom, in some sense. How, then, do we reconcile these apparently incompatible claims about the possibility of human freedom? This chapter explains Spinoza's basic conception of freedom, which means coming to terms with these difficulties.

This investigation leads me to two main conclusions, which are important to the coming chapters. The first is Spinoza's identification of freedom with rationality. While philosophers have long connected freedom and rationality, Spinoza does so on distinctive metaphysical grounds by conceiving of reason as having what he calls adequate ideas, which are caused by our own essential power or conatus, in other words, ideas of which we are the sole or adequate cause.