Before Ibn al-Haitham, most scholars believed the eye sent something out in order to see. He worked out that it is the other way round — light travels from the object into the eye.
He tested the idea rather than merely arguing it, which is part of why he is often credited with an early form of the scientific method. He is known across the world as the father of optics.
Part of the Muslim Scientists Series, introducing children to figures from the Golden Age of Islam through short, illustrated biographies.
