This is an important and beautiful book. The entire book is a narration from one speaker to another (who never speaks for himself). This narrator describes passing a  woman on a bridge, late one night. leaning against the railing staring at the water. He hesitated a moment, then went on. At the end of the bridge he walked down river for a bit when he heard a splash and a cry, repeated several times, which was going downstream; then it ceased. He wanted to run, but froze. Then it was too late to help.
    When a person makes a pivotal choice on their path and creates a belief that becomes a part of who they are -it becomes too late to change it. This is a kind of 'fall'.

“I sometimes think of what future historians will say of us. A single sentence will suffice for modern man: he fornicated and read the papers.”