VISION AND COGNITION IN THE NATURAL-PHILOSOPHY OF ALBERT-THE-GREAT (ALBERTUS-MAGNUS)

Albert the Great (Albertus Magnus, ca. 1197-1280) descended from a nob leman's family in Upper Suebia and studied natural philosophy and theo logy at the University of Padova, where he joined the Dominican order. Confronted with Aristotelian thought mainly in its Arabic modificatio n (Avicenna, Al-Farabi, Averroes, Alhazen, Costa ben Luca and others) from his days in Padova, he elaborated in several books on the princip les of natural philosophy, biology, brain and sense functions and psyc hology in addition to his theological and exegetic works. His observat ions and concepts on vision are discussed in detail. It is pointed out that Albert discovered some phenomena of vision not before known such as vestibular nystagmus and rod monochromacy, i.e. total colour blind ness accompanied by photophobia. Based on clinical observations Albert also postulated a decussation of the optic nerve fibres at the optic chiasm. Albert's concept of higher order cognitive function is discuss ed and some of his explanations of dreams and neuropsychiatric disease on the basis of his cognitive model are mentioned. Albert's thoughts on vision and other sense perceptions, higher brain functions and cogn ition are considered as progressive elaborations of Galenic concepts a s adapted by some Patristic theologians and the Arabic natural scienti sts and philosophers of the 9th-11th century.