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, signs and/or symptoms:
“But I will harden Pharaoh’s heart, and I will multiply my signs and wonders in the land of Egypt.”
—Bible: Hebrew, Exodus 7:3.
“So saying, her rash hand in evil hour
Forth-reaching to the Fruit, she plucked, she eat.
Earth felt the wound, and Nature from her seat,
Sighing through all her works, gave signs of woe
That all was lost.”
—John Milton (1608–1674)
“Social movements are at once the symptoms and the instruments of progress. Ignore them and statesmanship is irrelevant; fail to use them and it is weak.”
—Walter Lippmann (1889–1974)