After her aunt leaves, Catherine sits alone by the parlour fire for more than an hour, feeling old and grave as she judges Lavinia's foolish aggression. Her terrible plan ripens: she will speak to her father though she is afraid of him, and at eleven she knocks on his study door. She tells him she has not seen Morris again but would like to, not to say goodbye forever but to ask him to wait. Dr. Sloper calls her a dear faithful child, kisses her, and then asks whether she will make him happy by giving Morris up.
When she pleads for time and gradual persuasion, he turns affection into leverage, saying she may wait until he dies and that engagement to Morris means simply waiting for his death with impatience. Catherine answers with a desperate inspiration: if she does not marry before his death, she will not marry after. He treats that as another epigram, refuses ever to consent, and tells her to inform Morris that marriage without paternal consent means not a farthing of inheritance.
Catherine says that would be right, which confuses him, and when she asks to see Morris once, he opens the door as if turning her off, saying she will be cruel and ungrateful if she does. She sobs in the hall while he listens, then returns to his study thinking, by Jove, she will stick. The chapter is the emotional center of the book's battle: inheritance, duty, love, and fear are spoken with terrifying clarity.
Coming Up in Chapter 19
Dr. Sloper summons Mrs. Penniman and warns her that aiding Catherine's romance is treason in his house. Catherine, after a dreadful night, will still come down to breakfast and write Morris to meet her face to face..