Alhazan (c. 965 – c. 1040 CE)
Abu ?Ali al-?asan ibn al-?asan ibn al-Haytham (known in the West as Alhazan) born in Basra, present-day Iraq, wrote the influential Kitab Al Manazer or the Book of Optics, in addition to several significant books and chapters on philosophy, theology physics, mathematics, engineering, astronomy, medicine, psychology, anatomy, visual perception and ophthalmology. He: established the mathematical calculations to prove light travels in a straight line; developed the camera obscura (effectively a pinhole camera); proposed that eyes receive light reflected from objects, rather than emanating light themselves, contradicting contemporary beliefs including that established by Euclid; developed rigorous experimental methods of controlled scientific testing in order to verify theoretical hypotheses and substantiate inductive conjectures, very similar to the modern scientific method and consisted of a repeating cycle of observation, hypothesis, experimentation, and the need for independent verification; combined observations with rational arguments. The Book of Optics, written in Egypt during 10111021, has been ranked alongside Isaac Newtons Philosophiae Naturalis Principia Mathematica as one of the most influential books ever written in physics, and drastically transformed the understanding of light and vision.