The Unity of the Plot
In Book VIII, Aristotle again emphasizes the importance of a coherent plot, observing that some poets assume that if they write about the exploits of one character–Hercules, for example–their plots will automatically gain unity because the character's life can be viewed as a unity.

Life is not a plot, Aristotle argues. The events of a life, even the life of an imaginary character, must be sorted and organized. Homer, for example, does not include all of the details known about Odysseus's life in the Odyssey, but selects a series of events (the hero's homecoming) and assembles them into a consistent and unified whole. A successful plot relies on the discernment of the poet, who must identify that set and sequence of events that can be presented to the audience as a whole.

The test of the unity of a plot is that no part can be removed without changing and distorting the meaning of the whole. This interrelationship between part and whole remains fundamental to the field of literary hemeneutics, which maintains that each part of a work must be understood in relation to the whole, while the whole can only be grasped by understanding each of its parts.