Signs and Symptoms
Blindness is defined by the World Health Organization as vision in a person's best eye of less than 20/500 or a visual field of less than 10 degrees. This definition was set in 1972 and there is ongoing discussion on if it should be altered somewhat.
Read more about this topic: Blind People
Famous quotes containing the words signs and/or symptoms:
“All signs of superhuman nature appear in man as illness or insanity.”
—Friedrich Nietzsche (1844–1900)
“A certain kind of rich man afflicted with the symptoms of moral dandyism sooner or later comes to the conclusion that it isn’t enough merely to make money. He feels obliged to hold views, to espouse causes and elect Presidents, to explain to a trembling world how and why the world went wrong. The spectacle is nearly always comic.”
—Lewis H. Lapham (b. 1935)