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: Blindness
Famous quotes containing the words signs and/or symptoms:
“When it is evening, you say, It will be fair weather, for the sky is red. And in the morning, It will be stormy today, for the sky is red and threatening. You know how to interpret the appearance of the sky, but you cannot interpret the signs of the times.”
—Bible: New Testament, Matthew 16:2,3.
“A certain kind of rich man afflicted with the symptoms of moral dandyism sooner or later comes to the conclusion that it isnt 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)