How thin is a demon?

Widespread assumptions about the material constitution of demons in Roman and later antiquity have much to teach us about conceptions of the cosmos and the human person. Focusing on spiritual, psychological, or even the social implications of demons, the sophisticated readings of recent scholarship have proved so fruitful that more fundamental ideas about matter, physics, and biology are easy to miss. Exploring the physical “science” of demons, however, need not preclude their psychological interpretation. On the contrary, simultaneous attention to matter and spirit suggests that demons and people had more in common than we might otherwise suspect.