They juxtapose images of slim, seemingly perfect models alongside overweight individuals, insinuating that only the attractive can find love and acceptance.
His prose weaves together history, personal experience and arguments from his favourite philosophers; anecdotes about his napping schedule are juxtaposed with maxims.
In the expedition's Japanese stage, moreover, Goncharov's statements can be juxtaposed with independent sources that reveal the travelees' actual perceptions of the Russians.
Which, by the way, is another juxtaposition, because he's saying really funny things, but it's juxtaposed with his delivery, which is total straight man.