An exemplum (Latin for "example", pl. exempla, exempli gratia = "for example", abbr.: e.g.) is a moral anecdote, brief or extended, real or fictitious, used to illustrate a point. The word is also used to express an action performed by another and used as an example or model.
This genre sprang from the above, in classical, medieval and Renaissance literature, consisting of lives of famous figures, and using these (by emphasizing good or bad character traits) to make a moral point.
Collections of Exempla helped medieval preachers to adorn their sermons, to emphasize moral conclusions or illustrate a point of doctrine. The subject matter could be taken from fables, folktales, legends or real history. Jacques de Vitry's book of exempla, c. 1200, was one of the most famous collections. Geoffrey Chaucer's The Miller's Prologue and Tale became a vivid satire on these collections and the abuse they found wherever they were just brought into monotonous litanies. Examples include:
The Norton Anthology of Western Literature includes three exempla (singular, exemplum), stories that illustrate a general principle or underscore a moral lesson: "The Two City Dwellers and the Country Man" and "The King's Tailor's Apprentice" (both from The Scholar's Guide) and "The Cursed Dancers of Colbeck."
"The Friar's Tale" in Chaucer's The Canterbury Tales is a longer example of an exemplum.
A father tells the first story from The Scholar's Guide, and his son tells the second.
In "The Two City Dwellers and the Country Man," told by the father, the three traveling companions of the tale's title are on a pilgrimage to Mecca. Near their destination, their provisions are nearly depleted, and the two city dwellers attempt to cheat the country man by telling him that whoever of them dreams the most extraordinary dream shall get the last of their bread.
As the city dwellers sleep, the country man, alert to their intended deception, eats the half-baked bread before retiring.