Ibn al-Haytham writes the Book of Optics

1021

In Cairo, under house arrest for failing to dam the Nile, the Basra-born scientist completed a seven-volume treatise arguing that vision happened when light reflected from objects struck the eye. His experimental method, controlled and geometrical, was a foundation stone of the modern scientific revolution. The work overturned a thousand years of Greek theory and would profoundly influence Bacon, Kepler, and Descartes centuries later.