Body
The human body is a complex mode of Extension — a pattern of matter that strives to maintain itself.
In depth
Spinoza sees the body not as a mere vessel but as a complex individual composed of many simpler bodies working together. Your body is constantly affected by external bodies, and these affections are what generate your experience. The body has capacities we do not fully understand — "no one has yet determined what the body can do."
Why it matters
Spinoza elevates the body against traditions that denigrate it. Understanding what your body can do is central to understanding your mind, your emotions, and ultimately your freedom.