I think Evans wants to capture the regular side of people. The way they act during a normal day on the subways. If the people knew their picture were being taken, you would not be able to see the expressions they make. At that time, subways were fairly new to many. They saw faces they never knew, which made feel awkward and confused. In many of the photos, the subjects are not looking at the camera. You could tell that the picture was taken secretly. Back then there were people listening to music, reading newspapers, people talking. There would always be a mother and a child on the train. Today is the same, many people on the train do the same things as a century ago. The facial expressions are not that different. They mostly have the going-to-work-in-a-rush face. Occasionally there is a person sleeping on the subways. The people in the Depression Era, look somewhat more depressed, and emotionless. People on the subways today smile at other strangers they do not even know.
