If it's a pint glass for beer, then there's a debate to be had
If it's a wine glass then half full is perfect; if it's half empty then there's actualy only a quarter of a glass and then you're on a slippery slope ...
The real question with wine is whether the bottle is half empty ...
No, but I sometimes lower my expectations for the back 9 if I've had a good front 9. Let's say I'm 4 over, I don't expect to have another 4 over (just because I'm playing OK), half my handicap will suffice.....