Because we know there are people who call themselves knowledgeable about Austen out there who have never read Northanger Abbey, here’s a message right from the narrator:
Alas! if the heroine of one novel be not patronized by the heroine of another, from whom can she expect protection and regard? I cannot approve of it. Let us leave it to the Reviewers to abuse such effusions of fancy at their leisure, and over every new novel to talk in threadbare strains of the trash with which the press now groans. Let us not desert one another; we are an injured body.
From Volume I, Chapter V. Here endeth the lesson.