So similar to a parable, that it is usually considered a synonym, the rhetoricians' apologue is a brief fiction with pointed or exaggerated details, illustrating a moral truth without explicitly stating it. Unlike a fable, the moral is more important than the narrative details. Like the parable the apologue is a tool of rhetorical argument introduced in order to convince or persuade. For a good example of an apologue, see [1].

Montesquieu wrote a propos his Persian Letters "There are certain truths of which it is not enough to persuade, but which must be made to be felt Such are the moral verities. Perhaps a bit of history will be more touching than subtle philosophy."