Something that applies to all forms of storytelling:
“Not all guidelines are acceptable to everyone, and certainly there are several schools of thought regarding the importance of emotion. Some argue that plays communicate to the audience’s intellect when emotions are evoked. On the other hand, some echo Plato’s belief, later reinforced by Bertolt Brecht’s concept of “epic theatre”, that audiences stop thinking when emotional. (It should be pointed out that even Brecht’s plays do use emotional appeal, although he sometimes includes scenes or effects that briefly cancel emotional response.) In any case, wisdom points out that it is senseless to treat emotions and intellect like two unrelated parts of the human response. In fact, they cannot be separated.
Many theatre workers believe that plays are enhanced when characters have reason to experience strong emotions such as love and hate; the weaker versions such as “like a little” or “sort of dislike” are as unsatisfactory as musical minor chords. Without adequate motivation those emotions may degrade to soap opera qualities, but we can safely say that when characters care deeply about the issues and problems they face, the audience also will care, through the process of empathy. Not unimportant for the playwright, actors are apt to become more involved with characters who experience emotional ranges, resulting in powerful interpretations of a play.”
An extract from the book The Elements of Playwriting by Louis E. Catron