We all love to instruct, though we can teach only what is not worth knowing.
– Jane Austen
Pride and Prejudice, Chapter 54. When Elizabeth says this to Jane, she is expressing a reluctance to teach other people. She believes that some of the most important things can only be learned by oneself, maybe with a teacher to guide, but with the greater part of the work being done by oneself. Self-knowledge and self-awareness come from one’s own experiences and self-education.