For Spinoza, what it is for a body to be my body is simply that my mind represents that body. And, as we have seen, what it is for an idea to represent a body is for the idea to represent the body's place in a causal network, i. e. for the idea to be the explanation of the body in thought. This is another twofold use of the PSR. The mineness of my body must be explained, and it is explained in terms of the notion of representation and ultimately of explanation itself.
Spinoza (2008) - Three: The Human Mind