Here's a slightly different take on that. We know how optimists and pessimists see the glass....what about other ways of thought/life?
Realists - I can touch the glass. It exists. I can touch the water. It exists too.
Nihilists - None of this exists.
Absurdists - Why are you trying to derive meaning from a glass of water? You are not going to unlock the secrets of the mind with a glass of water. Now drink your damn water and get on with your life.
Kantianists - It doesn't matter what this glass of water is to me. It is my duty to consume it.
Rastafarians - Hey, man, it don' matta. Jus' chill.
"Smooth" Talkers - Enough about this glass of water, let's talk about you.
Narcissists - Enough about this glass of water, let's talk about me.
Surrealists - Whoah. Wouldn't it be cool if this cup was a melting clock, or like, an elephant?
Cynics - Why does the water have to be in a glass?
Non-Conformists - I'm not going to conform to any of your prejudices about who I am.
Conformists - What did the previous guy say?
Agnostics - Make the water prove it exists.
Republicans - No.
Democrats - Obama!
Analysts - Actually, since we've been talking, .064% of the water has evaporated, and the glass was not 50% full in the beginning, so, neither.
Defeatists - Is there really a point in answering this? You're going to write down half-full anyways.
Capitalism - I don't know, but I'll call it half-fullif I can sell the glass for more profit.
Communism - I hope you're going to divide the water among the masses afterwards.
Democracy - Which will get me the most votes?