How we cite our quotes: Citations follow this format: (Chapter.Paragraph)
Quote #1
"Thank you; for now we shall soon be acquainted, as I am authorized to tease you on this subject whenever we meet, and nothing in the world advances intimacy so much." (3.50)
Henry's ideas on friendship are closely linked to his sense of humor, which contrasts to some of the other views of friendship and 'intimacy' that we get in the book, namely those of Isabella.
Quote #2
Friendship is certainly the finest balm for the pangs of disappointed love. (4.6)
This is one of the best thematic statements in the whole text, since Northanger Abbey is not only concerned with romantic love, but with friendship as well. In fact, friendship might arguably play a more important role in the bulk of the text than romantic love.
Quote #3
The progress of the friendship between Catherine and Isabella was quick as its beginning had been warm, and they passed so rapidly through every gradation of increasing tenderness, that there was shortly no fresh proof of it to be given to their friends or themselves. (5.4)
Friendship has a lot to do with performance here, and it can be demonstrated or "proven" to others. The speed with which Catherine and Isabella pass through all the stages of friendship suggests that they are following some sort of prescribed, or set, route for being friends.