Since its publication in 1677, Spinoza's Ethics has fascinated philosophers, novelists, and scientists alike. It is undoubtedly one of the most exciting and contested works of Western philosophy. Written in an austere, geometrical fashion, the work teaches us how we should live, ending with an ethics in which the only thing good in itself is understanding. Spinoza argues that only that which hinders us from understanding is bad and shows that those endowed with a human mind should devote themselves, as much as they can, to a contemplative life. This Companion volume provides a detailed, accessible exposition of the Ethics. Written by an internationally known team of scholars, it is the first anthology to treat the whole of the Ethics and is written in an accessible style.