How we cite our quotes: (Act.Scene.Paragraph)
Quote #7
"What did you say? Oh, there's nobody there." (4.7.1)
Harpagon is so isolated by his greed that he often hallucinates that someone is talking to him. This comes partly from his paranoia, but also from a sense of loneliness that has to come with the territory of being so isolated. After all, the guy doesn't even want people in his house because he's afraid they'll find out where he keeps his money.
Quote #8
"Are you sure he's not hiding among you? They're all staring. Now they're laughing." (4.7.1)
After his money has been stolen, Harpagon looks to the audience for help. He even wonders if the thief is hiding among the people in their seats. But he quickly realizes that the audience finds his situation very funny, which just has to be an awful feeling for him. There's nothing worse than realizing that everyone is rooting against you.
Quote #9
"In future, four solid convent walls will answer for your conduct." (5.4.1)
Being an isolated old jerk, Harpagon decides that if his daughter Élise won't marry whomever he chooses, he'll seal her up in a convent and isolate her for the rest of her life as punishment. Maybe Harpagon doesn't think this is such a bad punishment. He's already isolated, but by his own choice.