The half glass full person is optimistic the barman is still serving.

Myself, I think a true optimist would see the glass always half empty. After all there is only ‘one glass’ any person should consider. The half glass full belongs to somebody else. My rational for this is as follows:

1. The glass to be considered is one’s individual glass.
2. This defines the liquid not to be water as most presume, but instead to be the ‘elixir of life’.
3. One should always sip/drink/swill from said elixir. (this might describe the person’s nature, but not the persons quality)
4. No one really knows how big their glass is. They only realise ‘in the end’.
5. Despite how one consumes the elixir, when it is gone it is finished. (ie. some lead full but short-lived lives, whilst some get old doing nothing).
6. The size of the glass is not a reflection of the quality of life. The taste of the liquid is.

For the reason I conclude it is a Half Glass (neither full nor empty, but always mine to drink).
This also sits with the notion that I am not waiting on someone else to satisfy me.

Where do you place the Horse and the Cart?

*Better to know life's question than pertain to know it's answer.