Is the glass half empty or half full?

Question for everyone. Is the glass half empty or half full?

The Engineer looked at me aghast and did not know what to say. Finally, he chirped up and said "it is obvious that it is half full of liquid and half full of air, so the only thing that counts is whether it moves." And the bartender nodded his head in agreement. Before everybody burst into song, the Scientist said " It is half full of liquid, the air is all around us, not just inside the glass..." Not it isn't, it is completely empty!" said the drunkard.