Ano Internacional da Luz 2015

Homenagem a Abu Ali Hasan Ibn al-Haitham



“Ibn al-Haytham is universally acknowledged to be one of, if not, the most creative scientist Islamic civilization had ever known.  He did not only critique the inherited Greek theories of light and vision, in his ‘Book On Optics’, and managed to create his own experimentally tested theories to replace them, thereby ushering the first building blocks for the modern understanding of how human vision takes place, but also subjected Greek cosmological doctrines in his other book “Doubts Against Ptolemy”, to a most devastating criticism that managed to undermine the very foundations of those doctrines, thereby initiating a sustained program of research to replace them; a program that lasted for centuries after him and culminated with the ultimate overthrow of the Aristotelian universe and the birth of the modern astronomy of the European Renaissance.”
Professor George Saliba of Columbia University, New York City, USA








“O dever do homem que investiga os escritos de cientistas, se tem como propósito chegar à verdade, é colocar-se a si próprio como opositor de tudo o que lê, e dele duvidar por todas as formas. Deve igualmente suspeitar de si mesmo ao examinar criticamente o que lê, de forma a evitar quer o preconceito quer a complacência.”


Ibn al-Haytham (latinizado: Alhazen)

(n.965, Basra, Iraque; m.1040, Cairo, Egipto)



 Image source: Typ 620.47.452, Houghton Library, Harvard University