In Poetics, Aristotle emphasizes the importance of a well-constructed plot. He defines tragedy as “a representation, not of people, but of action and life, of happiness and unhappiness” (65). Since the poet is imitating, or representing, “action and life” and not people, characters take a secondary importance to the plot to supplement and interact with it. To emphasize the distinction between plot and character, he states, “it is by reason of [the characters’] actions that they are happy or the reverse,” indicating that actions are integral in creating the consequences of happiness or unhappiness that are characteristic of tragedy (65). “Tragedy is the representation of an action,” he again writes (66). The singular indefinite article “an” implies that the scope of the plot should focus on a single action and its consequences. To represent this action, the poet must write the plot as a “unified whole” and omit inconsequential parts (68). He also emphasizes probability and possibility, stating, “Probable impossibilities are to be preferred to improbable possibilities” (92). He emphasizes this notion twice, later writing, “a convincing impossibility is preferable to an unconvincing possibility” (95). Thus, probability and the ability to convince an audience, or, in other words, believability, are closely related. His desire for unified and probable plots indicates that, for a poem to be good, it must be cohesive, believable, and tightly centered around a single action and its reaction.
Aristotle’s view of probability and unity aligns with Horace’s arguments throughout The Art of Poetry, where he is mainly concerned with consistency. In the second paragraph, he argues that poetry can be “anything you like” if it is “single and unified”, like Aristotle’s desire for the plot to be “a unified whole” (98). He then continues to emphasize this notion by instructing the poet to “[e]ither follow tradition, or invent something that is consistent within itself” in terms of narrative, characters, and presentation to avoid making an absurd impression (101). Horace demonstrates his aversion to absurd impressions by censuring artistic liberties that reach “the point of associating what is wild with what is tame, of pairing snakes with birds or lambs with tigers” — by pairing drastic opposites, he refers to things that are “neither probable nor necessary”, in Aristotle’s words (98). And, by tying the words “tradition” and “consistent” together, Horace implies that familiarity and patterns are paramount for good audience reception. With tradition, the audience receives something recognizable, allowing them to be immersed in the story immediately because they know what to expect. However, with new inventions, consistency allows the audience to become familiar with the rules of the narrative world throughout the composition and learn what to expect — they learn what is probable in the poet’s world. Thus, in the end, nothing should stand out as absurd in a good, consistent composition, no matter if the poet is working with pre-existing material or his own imagination.
But rather than focusing on action as central to a composition, as Aristotle does, Horace instead emphasizes wisdom as a crucial foundation for a good poem. As mentioned before, Aristotle bases his view of poetry on imitation. Horace does not explicitly describe imitation, but instead weaves the concept into his description of wisdom in poetry. He states that a “skilled imitator” should use “human life and character for his models” to “derive a language that is true to life” (107). Like Aristotle, who says tragedy is a “representation of action and life”, for Horace, poetry is also an imitation of “human life and character”. Since he lists “human life” and “character” together, he views action (“life”), and “character” as equally important, unlike Aristotle. Before, Horace mainly focuses on a composition being “consistent within itself”, but here, he also connects poetry to reality in aiming for a “language that is true to life”. Given that Horace speaks next of “maxims and well-drawn characters”, his use of the word “language” implies both the poet and his characters’ manners of expression (107). This is similar to Aristotle’s assertion that characters must be “lifelike” (76). Thus, poetry imitates human reality in all aspects, from action and character to language and life.
By emphasizing internal consistency and verisimilitude and disapproving of improbable events, Horace points to the ideal form of poetry as cohesive, believable, and unified. Despite their differing approaches, both Poetics and The Art of Poetry point toward the importance of convincing consistency.