He used them to illustrate a political point, or, more frequently, to humanize himself with his audience.
The scene is meant to illustrate how depraved his character has become, but the moment is a turning point for another reason.
But it was well worth it—the Reys went on to author and illustrate more than 30 books, seven of which star Curious George.
1520s, "light up, shed light on;" 1610s, "educate by means of examples," back-formation from illustration, and in some cases from Latin illustratus, past participle of illustrare (see illustration). Sense of "provide pictures to explain or decorate" is 1630s. Related: Illustrated; illustrating.