MIRRORS. Object and symbol, instrument of knowledge and type of reflection or speculation (the Latin word for mirror is speculum), means of visual perception and hallucination: there is scarcely a single culture that has not been interested in the mirror, first in its primitive form—a bowl filled with water, a sparkling stone (jade, obsidian)—then in more elaborate guise—polished metal discs (bronze, silver, or steel), a mirror of balloon-shaped mediaeval glass—and, finally, in the form of the plane mirror, clear as rock crystal. Because it reflects an image of the self that the eye is unable to see directly, because it traps light, because the effect of the reflection is to reveal an unseen "other," and because it faithfully reproduces its subject while making it seem different—that is, reversed—religions have made the mirror central to the mystical life and knowledge of self.

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