What are Benjamin Fatalist quote in The Fatalist short story by Isaac Bashevis Singer

How does the author use structure to create tension in the excerpt

"as one of our outstanding historical figures once said, ‘when a great democracy is destroyed, it will not be because of enemies from without but rather because of enemies from within.’" (paragraph 7) how does this quote reveal mccarthy’s point of view and advance the purpose of his speech?

What is one way to appeal to ethos?