It's actually ha-
If e=mc² then we must divide half
Of the cup depending on what type
Of meterial it is ,must me a clay cup
If yes then the atoms of the ²route of 2
Is 1 (probably) estimatedly the cup
Must be disolving the water if yes then 1mm
Per day so we need to multiple that by
2 as if it was day and kept out ,the atom
Of the water (hydrogen and oxygen) it
Wold have a chance of 80% of becoming into
It's gassous version, thus in 1 month the cup will remain empty.....
If you are talking about the metaphor, yes you are correct its how you see it, but if you are talking about the actual action of filling a glass halfway, then according to the english language, yes, the glass is half full/filled