Cocteau contemplates the french words for angel (ange) and angle (angle).
He reflects that by adding an 'l' (aile) to an ange, we have constructed an ang(l)e. The aile, which sounds 'l' in english, means 'wing' in french, completing the image in both languages.
This association between Angel and Angle enables Cocteau to comment upon the properties of the double image, which may be expressed as the following fourfold:
Angel <> Reflection
Angle <> Refraction
The Angel represents 'Becoming' for both Cocteau and Rilke. Cocteau's struggle with the Angel Heurtebise can be seen as a struggle with the poetic Muse, or with Poetry Itself.
taken from here after reading Jean Cocteau's White Book