Ibn al-Haytham

Ḥasan Ibn al-Haytham, Latinized as Alhazen[14] (/ælˈhæzən/;[15] full name Abū ʿAlī al-Ḥasan ibn al-Ḥasan ibn al-Haytham أبو علي، الحسن بن الحسن بن الهيثم; c. 965 – c. 1040), was an Arab mathematician, astronomer, and physicist of the Islamic Golden Age.[16][17][18][19][20] Referred to as "the father of modern optics",[21][22] he made significant contributions to the principles of optics and visual perception in particular. His most influential work is titled Kitāb al-Manāẓir (Arabic: كتاب المناظر, "Book of Optics"), written during 1011–1021, which survived in a Latin edition.[23] A polymath, he also wrote on philosophy, theology and medicine.[24]

Alhazen Ḥasan Ibn al-Haytham
ابن الهيثم
Personal
Born	c. 965 (0965) (c. 354 AH)[1] Basra, Buyid Emirate
Died	c. 1040 (1041) (c. 430 AH)[1] (aged around 75) Cairo, Fatimid Caliphate
Religion	Islam
Denomination	Sunni[2]
Creed	Ash'ari[2][3][4][5]
Known for	Book of Optics, Doubts Concerning Ptolemy, Alhazen's problem, analysis,[6] Catoptrics,[7] horopter, intromission theory of visual perception, moon illusion, experimental science, scientific methodology,[8] animal psychology[9]
Muslim leader
Influenced by Aristotle,[10] Euclid,[11] Ptolemy,[12] Galen, Banū Mūsā, Thābit ibn Qurra, Al-Kindi, Ibn Sahl, Abū Sahl al-Qūhī
Influenced Omar Khayyam, Taqi ad-Din Muhammad ibn Ma'ruf, Kamāl al-Dīn al-Fārisī, Averroes, Al-Khazini, John Peckham, Vitello, Roger Bacon,[13] Johannes Kepler

Ibn al-Haytham was the first to explain that vision occurs when light reflects from an object and then passes to one's eyes.[25] He was also the first to demonstrate that vision occurs in the brain, rather than in the eyes.[26] Ibn al-Haytham was an early proponent of the concept that a hypothesis must be supported by experiments based on confirmable procedures or mathematical evidence—an early pioneer in the scientific method five centuries before Renaissance scientists.[27][28][29][30] On account of this, he is sometimes described as the world's "first true scientist".[22]

Born in Basra, he spent most of his productive period in the Fatimid capital of Cairo and earned his living authoring various treatises and tutoring members of the nobilities.[31] Ibn al-Haytham is sometimes given the byname al-Baṣrī after his birthplace,[32] or al-Miṣrī ("the Egyptian").[33][34] Al-Haytham was dubbed the "Second Ptolemy" by Abu'l-Hasan Bayhaqi[35] and "The Physicist" by John Peckham.[36] Ibn al-Haytham paved the way for the modern science of physical optics.[37]