So far as possible, they should act out what they are writing, even down to the characters' movements and gestures. If two writers are of equal natural ability, the more convincing will be the one who [also] shares the actual emotions, blustering like a blusterer, ranting like someone furious. Writers need to have sympathetic natures or be slightly mad. The first kind easily understand the emotions [of the characters], the second kind feel those emotions in person.
- Aristotle's Poetics