The figure of the putto (often portrayed as a mischievous baby) made frequent appearances in the art and literature of Renaissance Italy. Commonly called spiritelli, or sprites, putti embodied a minor species of demon, in their nature neither good nor bad. They included natural spirits, animal spirits, and the spirits of sight and sound, as well as hobgoblin fantasies, bogeys, and the spirits contained in wine. Among the sensations ascribed to spiritelli were feelings of love, erotic arousal, and startling frights.

After discussing the many manifestations of the...