A Lexicon of Light

The 20 words defined in this lexicon reflect the ways in which light irradiates the atmosphere, the universe, and our perception of the world. Because no single system—scientific, religious, philosophical, or cultural—can possibly encompass every meaning of light, this lexicon is systematically unsystematic, exploring each of these realms through words that serve as synecdoches for ways in which we understand light and its myriad effects. 

AURORA

A flaring ring of light illuminating the night sky. Each of Earth’s poles has an aurora, which can occasionally grow large enough to be seen near the equator, inspiring visions of apocalypse. (In the biblical second Book of the Maccabees, the aurora borealis is described as “horsemen charging in midair, clad in garments interwoven with gold.”) For the Inuit, who are more accustomed to it, the aurora is perceived as a football game played by spirits in the heavens. The scientific explanation is no less astounding. Charged particles cast off by the sun are carried by our planet’s magnetic field toward the North and South Poles, colliding with atmospheric gasses and causing them to glow like neon signs.

CAMERA

A device for making photographs. Even before the invention of photography, the camera was a tool for recording observations, preserving the three dimensions of reality on a two-dimensional plane. The camera obscura—a dark room with a small hole that projected outside scenery onto a blank wall—was well known to Aristotle, and aided landscape and anatomy drawing during the . The challenges of working with a camera lucida—a related optical instrument—led William Henry Fox Talbot to co-invent a process he called of reality we actually see.