On my way home from Klaudio’s, I am watching the moon. It appears to hang right above me. Three days short of full, it lights my way down Borgo quite splendidly. Just before I reach my door, it crosses my mind out of the blue that the moon can actually never be full. At least not from anyplace on earth. To be really full, the moon would have to be seen from some point along the line connecting the center of the sun and that of the moon. Looking from anyplace on earth, this would entail either a partial or total eclipse of the moon. Whenever the moon appears to be full, the sun actually lights it at some small angle so as to bypass the earth. The notion of full moon is only due to the poor visual acuity of the human species. As I am unlocking my door, I start wondering about this belated discovery. How is it possible that I have realized only now that the moon can never be really full?