Satire. Satire is a biting literary tool, one that Geoffery Chaucer used liberally when he wrote his Canterbury Tales. Webster's New World Dictionary says that satire is "the use of ridicule, sarcasm, etc. to attack vices, follies, etc." Using that definition, I think that all of the pilgrims in the Canterbury Tales are satirized to some extent; some of the satirizations are more subtle than others. The Knight is one of the pilgrims that is more subtly satirized.
Chaucer satirizes knights and chivalry in two different ways: in the prologue and in the Knight's Tale. The first way in the prologue is with the pilgrim Knight's character. Chaucer wanted to present a realistic knight, but he also wanted to give the Knight some very real, and obvious flaws, as a sort of social commentary on the way that knight's were perceived in the 14th century. To that end, he gave the Knight some qualities that could be termed as the antithesis of the qualities that a good and honorable knight should have. The second way I see Chaucer as satirizing chivalry is through the Knight's Tale. The Knight's Tale presents the "ideal" knights. They follow the codes of chivalry. They follow the graces of courtly love. They have duels. Have battle honorably. And, they also make fools of themselves on more than one occasion. Palamon and Arcita are so perfect, that they become parodies of the perfect knights. And, in the end of the tale, everyone ends up somewhat unhappy, and there is no clear winner. By writing this parody, Chaucer is trying to convey the idea that a lot of the ideals of chivalry are a bit silly. And, as all of the different tales reflect back on the characters of the pilgrims who tell them, the ideas in the Knight's Tale can be reflected back on the Knight.
In the article "Costume Rhetoric in the Knight's Portrait: Chaucer's Every-Knight and his Bismotered Gyphon," by Laura F.