The glass half full / empty question is used often to see if someone is a pessimist or an optimist. To some, saying that the glass is half full, is using a euphemism and that you're lying to yourself. Those who see the glass as half full, will argue that the pessimists are downers and looking at the world as half empty is depressing.
I've never really looked at the glass as half empty or half full. The reality is, there is half a glass of water. Whether or not the glass is half empty or half full is irrelevant; it's what you do with this bit of information. Regardless which side of the fence you sit on, the fact of the matter is, there is 50% there. I don't care if you think it's 50% full or 50% empty. The fact remains that there is 50%. The more important question, is what are you going to do with that 50%?
Are you going to complain and whine that you didn't get 80%? Are you going to enjoy the remaining 50%? Or maybe, are you going to see what you can do with that 50% and see if you can't increase it to 55%?
The reality of the world cannot be changed. If you break an arm, it's broken. It doesn't matter what euphemism you use. It really doesn't matter to me if someone should be considered visually impaired, or if someone is blind. Regardless of politically correct terms and / or euphemisms, the fact remains that this person can't see. What's important, is what they do with this bit of fact. Arguing that we have to be politically correct and calling them visually impaired doesn't change the fact that they cannot see.
The question remains. What are we going to do about it? Because arguing about the phrase / term that's used doesn't fix / rectify / solve anything. Instead of debating about labels, we should more interested in what next steps we can do to make things better. And while you can't change the reality that's in front of you, there are always still choices. You can deal with it with a smile, or you can deal with it with a frown. Either way, you're still going to have to deal with it.