Ibn Al-Haytham: The Father of Modern Optics
After failing in his attempt to regulate the flow of the Nile, Ibn Al-Haytham feared that al-Hakim would punish him. To avoid punishment, he pretended to be insane until al-Hakim's death. He also traveled to Spain and during this period, he had ample time for his scientific pursuits, which included optics, mathematics, physics, medicine and development of scientific methods -- on each of which he has left several outstanding books.