This woman is reading from a book to the man laying behind her. Every once in a while he lift up his head, when he hasn't understood, to ask her to repeat it. Then he looks at her. For the rest he listenens and she reads. Nice form of communication, especially observed from a distance.

I filmed a man who was simultaneously walking and reading.
This way I captured the world for him that was passing him by.

The loosely held pages tremble and move up and down. Through the motion of the subway but also through the natural trembling of the man’s hand and arm.

Show the resemblance between pages and thoughts: first film the loose pages and then move the camera up to his head. Then keep the camera still and focus on his forehead.