Diction, or word choice, is another source of greatness in writing. In the next set of chapters, Longinus discusses how to select the most beautiful and apt words. Effective word choice brings the following aesthetic qualities to prose: “grandeur, beauty, mellowness, weight, strength, power, and a certain brightness” (41). “Weighty words” are not to be used on all occasions, however, only where they are truly appropriate.

After a lacuna in the text, Longinus’s first examples of effective diction are vulgarisms: commonplace, coarse, or earthy words and expressions. Their expressive power is sometimes preferable to that of more refined diction because vulgarisms are connected with “our common experience” (41), and “what is familiar is more convincing” (42).

Longinus praises Plato’s use of metaphors for the parts of the body (43). Such metaphors have a “natural loftiness” and bring us “delight.” Metaphors must “appear necessary” and convey emotion, and writers should limit their use of metaphors to two, or at most three, in a single passage.

After another lacuna in the text, Longinus discusses hyperbole, a form of amplification through exaggeration. Comic hyperbole, for instance, exaggerates the small so as to provoke ridicule and laughter.