This morning (14-04-1988) I woke up with 'Musikalisches Opfer' from J.S.Bach. This music comes straight from heaven. I became interested in this after reading 'Goedel, Escher, Bach' from D.Hofstadter. The persons in the title refer to people whose works involve selfreflection. Goedel made a mathematical theory about other mathematical theories. Escher made famous selfreflecting drawings.
A hand is drawing another hand which is drawing the first drawing hand:
        
On the 'Musikalisches Opfer' Bach made many compositions which reflect upon themselves (fugas, canons etc.).
Some links
Biography Bach
Escher

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