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Is this an oxymoron?

  1. Jul 14, 2006 #1
    People are always saying they are "legally blind" without their glasses on. However, the definintion of "legally blind" is "Central visual acuity of 20/200 or less in the better eye with corrective glasses or central visual acuity of more than 20/200 if there is a visual field defect in which the peripheral field is contracted to such an extent that the widest diameter of the visual field subtends an angular distance no greater than 20 degrees in the better eye.

    So technically you can't be legally blind without your glasses if your vision is better than 20/200 with them unless you have a severe visual field defect (tunnel vision).

    Is this an oxymoron or is there another term to succintly describe this particular misuse of legally blind?
  2. jcsd
  3. Jul 14, 2006 #2


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    That must have been writen by an optomist.
  4. Jul 14, 2006 #3


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    Optomist, optometrist hilarious. As for the oxymoron question I have no clue as I was rubbish at english.
  5. Jul 14, 2006 #4


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    I think you're right. When people say they are legally blind without their glasses, they simply wish to make a distinction from "blind", which is usually interpreted as "fully blind".

    They just mean that "their vision is so bad that, if they had this vision (even with glasses) they WOULD be legally blind".
  6. Jul 14, 2006 #5


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    Nope, not an oxymoron, but more of hyperbole...an exaggeration for emphasis. It's a way of explaining how bad their natural eyesight is without the marvelous invention known as the lens.
  7. Jul 15, 2006 #6


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    It's not an oxymoron, and it's not quite what I'd consider a hyperbole. More than anything else, it's simply wrong, or at least imprecise, use of terminology.

    Legal blindness is the condition of possessing a severe enough visual defect that is not amenable to simple refractive correction. Two conditions define the visual defect, they need not be mutually exclusive : the first is a visual acuity of less than 20/200 in the less severely afflicted eye. The second is loss of peripheral vision to less than 20 degrees of aperture in the less severely afflicted eye. If either or both of these conditions are met, *despite* the use of appropriately applied refractive correction, then, and ONLY then, is the person said to be legally blind.

    So it simply doesn't make sense for someone to say they're "legally blind without their glasses". Next time, you hear them say that, correct them. If they insist they're using it right, tell them they just might be "legally moronic" as well.
  8. Jul 15, 2006 #7
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