20 Ways to See the Light
The meaning of light through history in science, religion, philosophy, and culture
By Jonathon Keats
“That natural agent or influence which evokes the functional activity of the organ of sight.” So begins the first definition of light in the Oxford English Dictionary (OED). Additional definitions range from “the inward revelation of Christ” to “the answer to a clue in a crossword puzzle,” yet the seven pages of the OED devoted to defining light scarcely begin to approximate all that light means to us, let alone the significance of light throughout time. In the 13.7 billion years since the universe formed, photons have effected nearly everything, and in the 200,000 years since our species emerged, light has been as central to our existence as water and carbon.
The 20 words defined in this lexicon — from aurora to ziggurat — reflect the ways in which light irradiates the universe and illuminates 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.
