Sentence:  This passage is virtually the <WSD>peroration</WSD> of the "Ethics"; the few paragraphs that follow are concerned with the transition to politics. 
Meaning of the word marked with <WSD> tags:  The concluding section of a discourse, either written or oral, in which the orator or writer sums up and commends his topic to his audience, particularly as used in the technical sense of a component of ancient Roman oratorical delivery.