1. i think  Richard Avedon mean when he calls the face complex,connected and contradiction is the face has lots of detail and can be compared to a piece of art or in some way a piece of fashion because he use to do fashion photography that what i think he means when he says the face is complex,connected and contradiction.

2.i feel like he achieved something more simple but with the same complexity as fashion photography 
without using lot of prop and stuff and with the white background help you focus on the person then props or cloths.

3. i think he mean a photo capture a moment or a statement in time and leave it there
forever.