In preparation for a podcast episode on the mirror delusion, I thought it a fitting time to dip back into the Phobia of the Week series here on the blogs. After all, there's something rather profound about a psychiatric disorder that leads you to believe your body (or a certain part) is composed of fragile glass.
While modern psychologists point to a handful of contemporary cases, mirror delusion was largely a late-Medieval affair. Most of the reported suffers were melancholic, learned men who were likely to read medical and literary accounts of glass delusion and thus absorb it into their own psyche. Furthermore, the notion of the human body as a breakable vessel roots itself into biblical traditions and rises to prominence in an age of increased familiarity with glass as a luxury material.
Terror Management Theory posits that the terror of impermanence (and the quest for immortality) underlies all human endeavors, and a stained glass window presents a wonderful metaphor for mortality. It's a piece of unparalleled beauty. It captures the sun, transforms pane and space into an optical work of art.
And yet the glass is a fragile luxury. The slightest stone, a falling tree limb, a bird, hail stones or a peasant's rock can crack or even shatter it. In the words of Cormac McCarthy, we come to realize "flesh is so frail it is hardly more than a dream."
And such glass technology serves as a tantalizing, metaphoric mind-trap for the educated, contemplative European of the day. Factor in psychiatric susceptibility for delusion and our brooding, 16th-century bookworm might well come to believe his buttocks are made of glass.