I don't believe we ever see two gentlemen speak alone in Austen (which makes sense, since she advised to stick to what you knew). So I decided to stray from her (usually good) advice and explore what these two men in particular would say to each other: they're vastly different people, and yet also were raised together by the same strong force of nature (the 3 gentlemen my title refers to). They're pushing each other, because that's the pattern of behavior they know to fall into. Will it change though? That's part of what the book seeks to explore.
