Half Empty?

So is the glass half empty or is the glass half full?
I guess it all depends, of course, upon your frame of mind.
Some people will keep searching; they’re never satisfied.
They’ll dig and dig and dig some more to see what they can find.
They never stop to question the way that others live.
They only think about themselves. They might as well be blind.
That glass is always lacking; it never is enough.
They fear that someone else has more and they’ll be left behind.
But those that see it half full are much more satisfied.
The lives they live are sure to be more full, more rich, more kind.