Not the whole story. There is also dissolved oxygen bonded to water molecules in addition to the oxygen atoms within the water molecules. So if the glass looks exactly half full it's probably actually slightly less than half in reality.
The glass is always completely full*. The question is what proportion of the content is water (including solutes etc) and what proportion atmospheric gas. *although you can still get more 'stuff' in.
My glass is always half full, cracked and you can still see the remnants of the lipstick that last woman to use the glass had on - but enough about my life. In terms of the club, I think it is half full of a rather nice and expensive wine which is very enjoyable and tasty and I want to thank the owner of the club for filling my glass thus (I'm not drunk honest)
It all depends on expectations really. If you ask for a glass of water because you are thirsty and you're given half of one then obviously that has to be half empty because you were expecting it full. It is half full if you're grateful to have any water whatsoever and expected none to be given to you in first place.
Can I be the dick that says while you lot were deciding if the glass was half full (optimist) or half empty (pessimist) I came along and drank the contents (opportunist)? Yes, yes I can.
I hate to break it to you, but the glass of water was proverbial, and the writing is still there so you didn't drink the words either.
They are both the same and doesn't mean you are negative or positive based on what you say. Why is half-empty bad? If your beer glass is half empty then you are only a half away from getting another pint in. Why is that bad? Especially if you are at beer festival and want to try as many different beers as possible.
And how do we know the glass is not a figment of the imagination, or that we are all here - we may not exist
Is it right that if you view your glass as half full you're quite a positive person whereas people who view their glass as half empty have, in general, a more negative outlook?