I watch the homeless man walk past the screens. There are two stacked into a stainless steel frame, showing the movements of passengers along the platform via the CCTV-cameras hanging from the ceiling on either side. Children like to play around with their projected images, running back and forth in front of the screens until their phantom copies appear and disappear again and again.

The homeless man stops and stares for a second, then raises his fist and hits the top screen. It is not a violent gesture; it seems matter-of-factly. A few minutes ago he had tried to sell the homeless newspaper on my U-Bahn, friendly and nicely asking for change. I think that maybe he cannot show his contempt for the frozen faces on the train ignoring him and staring into nothingness, but the screen allows him to do so for the recycled projection of humanity inside the metal frame.

The doors of my train close and we leave.