Ibn al-Haytham

Ibn al-Haytham was a scholar working in Basra and Cairo whose Book of Optics, written around 1011 to 1021, overturned the ancient idea that vision works by rays sent out from the eye and argued instead that sight results from light entering the eye from external objects. He built his case through controlled experiment and mathematical reasoning rather than appeal to authority, a method historians credit as an early form of the modern experimental scientific method. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/