Angels do not exist, and yet they are divided into orders much like the hierarchy in an army. They fly to and fro in frescoes, act as the bearers of glad tidings in the paintings of Raphael and Giotto, serve as stone guardians by the graves of the rich in Buenos Aires and Genoa, and accompany the doomed to the outer gates of Paradise with their flaming swords held high. They have names, bodies and wings; they are genderless and yet they are not women; they are immortal, which means that no skeletal remains have ever been found, so that no one has ever been able to examine them to find out how those gigantic wings are connected to their shoulder blades - in short they are part of the world around us even though they do not exist ....