I've read trough "About The Face", w and here are some points that promoted consideration.
It's only a fragment :
"People were coming face to face with their images for the first time, and <...> had never even seen a clear and crisp reflection of themselves in a mirror"
SO, they haven't seen themselves trough the whole life, but they had to hold some kind of image of their faces in their heads.. So this projection of their face, (undisturbed by the actually known appearance of it) is what's the most interesting for me.
Could this image resemble the "inner-face" (soul, the essence of the personality) just by a tiny bit?
And one more interesting line:
"Love of portraits may be regarded as an index of civilization itself"