Cliff asked:

Is the glass half empty or half full?

If you drank from the glass when it was full, it's half empty.

If you fill it half way when it's empty, it's half full.

Is this like a 'which came first' philosophy question? i.e. the chicken or the egg?

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If you are trying to puzzle us with those questions, I think you can do that even better with this
paragraph of the Chinese 'tao te ching', give it a look!

"The Way (Tao) is like an empty vessel
That may yet be drawn from
Without ever needing to be filled.
It is bottomless: the very progenitor of all things in the world...

It is like a deep pool that never dries. I do not know whose child it could be. It looks as if it were prior
to God."

Arthur Brown

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