I know parables, metaphors, and figures of speech rely for their effectiveness on their clarity, brevity, and simplicity. But sometimes, they're just two simplified to be illuminating.
Take the "glass is half full/empty" figure of speech.
I don't think I know a single person who would look at the proverbial glass of water and say either of the two proverbial options. I don't know anyone who is, simply, a glass-is-half-full kind of guy, nor a glass-is-half-empty kind of gal.
Now, me? I look at the glass and say, "Wow. We are so lucky that this glass is half full of water--do you realize how many things could have gone wrong with getting the water into the glass?"
Stephen? He's more likely to say, "The glass is already half empty. We need to think about what we're going to do with the rest of the water--what are all our options?" Except for when he says, "Well, the glass is half full. But do you realize how many things could still go wrong and then where will the water be?"
Isaac? "Water!! Can I have it? I'm really thirsty."
Mom? "Okay, this is a good start. Water is at the lowest level of Maslow's hierarchy of needs. We do need to move on from here, though."
Tia Marleny? "Mom, I got this glass of water for you! I only filled it up half way, because I knew you were exactly this thirsty. That's why you like me best, isn't it?"
Dr. Hall? "It's only because we're trapped in an ethic of scarcity that we would even worry about questions of whether the glass was half empty or half full. What we need to be able to see is that there is more than enough water to meet our needs."
Dad S: "You know, this reminds me. I went to school with a guy named Fred Hammersmith, and he got married and moved to Nebraska and had three kids. Well, one of them worked at a water bottling company for about four years after he finished college--he went to Kansas State on a lacrosse scholarship--and the last time I saw him (I think it was at a Christmas party at his parents' house) he told me an interesting story about how they measure the quantity of water that goes into each bottle."
Dr. Hauerwas? "Who was it that taught you to measure the water by the glass that it's in? Why is the value of the water correlative to the glass of any importance to us?"
Grandma Jackie: "Oh, look at this, Jane! This glass is half full, but
I only paid twenty-five cents for it, because I took it to the guy at the counter and
I said, 'Hey! This glass is half empty!' And he gave it to me for twenty-five cents! It was three dollars, Jane, and I got it for twenty-five cents!"
Theo: "I can put my meatball in my water, Mommy?"
See? There are so many kinds of people in the world. You really can't limit yourself to those two options.