Extramission Theory

Extramission theory is an early model of how vision was understood in ancient philosophy and science. It says that the eyes, like a flashlight, outwardly project rays, light, or a visual power outward into the surrounding world, and when these rays reach an object, vision occurs through contact between the eye and what is seen. This model helped explain distance vision, attention, and focus in pre-modern and pre-scientific thought. Extramission theory was influential in the ancient Near East, in Greek philosophy, and is referred to in the New Testament and Rabbinic traditions well into antiquity. Later discussions of perception and remained important in philosophical and metaphorical language long after scientific models of vision became dominant.