As in Austen's other work, the marriage plot predominates, but the central themes are found in the characters' interactions with each other and the degree of intelligence, humanity, capacity for growth, and kindness they bring to their inherited social positions. Emma, who has so many gifts, abuses them for much of the novel by trying to rearrange other people's lives—she manipulates Harriet Smith's emotions, hurts those of Miss Bates, all the while not knowing where her own feelings really lie. It is her discovery, guided by Knightley, both of her shortcomings and her real feelings that in a sense earn her betrothal to Knightley. Yet Emma's machinations, reprehensible as they may be, serve not just to expose her moral shortcomings, but the failings of others and of the social system itself. This exposure is particularly evident in the secret engagement between Frank Churchill and Jane Fairfax—subterfuge forced upon the couple by superficial considerations about money and propriety, and made especially painful for Jane when Churchill flirts with other women in her presence and then ignores her, all to conceal the engagement. Indeed, an encounter between Emma and Churchill toward the end of the novel (Chapter 18 of Volume 3) shows each admitting to the other the manipulative nature they share.

Adding to the sense of complexity of the social system is the capricious ease with which some characters fall into personal happiness and prosperity without themselves suffering very much, while others achieve happiness only after long and patient struggle. Jane suffers far more than Frank in the course of their secret union, and Knightley is overtly jealous of the twenty-three-year-old Frank Churchill being handed a fortune and marrying Jane, while he is to marry Emma, whom he has known since she was a child, only after a long, careful vigil (Chapter 13, Volume 3). Churchill, in a slight way, is socially stigmatized by his own passions in arranging the secret engagement (which Jane at one point calls off), but yet his youthful rashness is ultimately rewarded. The coincidental death of Mrs. Churchill, his aunt, has also played right into his hands: She would have opposed the marriage and refused any financial backing.

Breaches of propriety and abuses of language find expression here as in Austen's other novels, most dramatically in the famous Box Hill outing, reminding one of Austen's pervasive concern with propriety and decorum for the sake of human dignity and happiness. In addition to Churchill's blatant flirting with Emma and its repercussions on Knightley and Jane Fairfax, there is Emma's abuse of Miss Bates and the events that lead up to it. After annoying Mrs. Elton, the self-proclaimed chaperon of the party, by preempting a leadership role—a perhaps forgivable breach—Emma starts a conversation game in which each person may contribute "one thing very clever, ... or two things moderately clever—or three things very dull indeed." Miss Bates takes the bait and offers "three things very dull indeed." Emma quips back, "Pardon me, but you will be limited as to number—only three at once." Miss Bates is very hurt, and apologizes about her loquacity to Mr. Knightley, yet she also notes Emma's rudeness. Later, Knightley confronts Emma with her cruelty, reaffirming the imperative that well-placed, intelligent people need to behave in a caring manner towards others, regardless of their perceived lack of intelligence. The Box Hill sequence suggests how polite behavior can mask many complex passions and motives, but also that, as often as not, there is a reason for masking them.

Gossip is a breach of decorum and abuse of language that apparently only becomes so when it...