What we read into the faces we stare at or what we project onto them can be all valid, but they are all just a slice of the truth.

“A portrait is not a likeness. The moment an emotion or fact is transformed into a photograph it is no longer a fact but an opinion. There is no such thing as inaccuracy in a photograph. All photographs are accurate. None of them is the truth. ”
― Richard Avedon

The person sitting on the tube opposite or the person projected on the wall can become a white canvas ready to be coloured up by your own prejudice and imagination.

Life is witten on their faces – wrinkles, tattoos, posture, clothes- they all talk about the person behind it .

Which slice of the second, which angle of the face, which posture you pick as a photographer is entirely up to you. Therefore You more, like anything are written on their faces.