I certainly esteem myself a steady, reasonable kind of body… I have undergone sharp discipline, which has taught me wisdom; and then, I have read more than you would fancy, Mr. Lockwood.
Nelly states her credentials as narrator: experience and reading. ‘Discipline’ that ‘taught’ her personifies hardship as a tutor, and she’s proud of having learned. She’s conscious of class prejudice and quietly pushes back. The line reminds us that the great chronicle of Wuthering Heights comes from a working woman’s mind. It invites trust while hinting that her ‘wisdom’ has edges and blind spots. She reminds Lockwood that books and labor can live in the same pair of hands.