Emma is the only Austen book in which “money is no object”. Well, not for the main characters, anyway. In all five other stories money, or rather the lack thereof, is the key driving force behind the plot.
Think about it:
Northanger Abbey: General Tilney pushes Henry to court Catherine because he thinks she’s rich. He kicks her out when he finds out she’s not. If he hadn’t made Henry pursue her, the whole thing might have fizzled into a Bath flirtation, and nothing much might have come of it, but as is, Henry is emotionally and “in honour” engaged, so he marries her.
Sense and Sensibility: the Dashwood women’s being poor makes them move to Devonshire, where they meet Willoughby and Colonel Brandon. Edward can’t marry Elinor, because she’s poor; he gets in trouble over his engagement to Lucy because she’s poor (if either girls were wealthy, his mother wouldn’t blink at his marrying one of them) and the trouble results in him being poor, too. Willoughby dumps Marianne because she’s poor and he needs a rich wife… The whole thing revolves around poverty and inheritance.
Pride and Prejudice: the entail. Need I say more? Well, okay then: the Bennet girls must marry, or they’ll end up destitute. But they’re poor prospects because of their lack of dowry. Their mother is fully aware of this, which makes her the rapacious and obnoxious son-in-law hunter, which disgusts Mr Darcy, leading him to convince Mr Bingley to drop Jane (temporarily, anyway). Mr Collins proposes to Elizabeth to make up for inheriting her father’s estate. Wickham runs off with Lydia and needs to be bribed to marry her. Money money money…
Mansfield Park: Fanny is the poor relation and thoroughly downtrodden for it. Her family’s poverty is what makes them rather less than respectable. It’s sheer folly for her to turn down Mr Crawford; economically, she’s one step away from condemning herself to penury (there’s a good chance she’ll end up a poor old maid like Miss Bates), which makes her uncle very angry at her. Mary Crawford is after Edmund, or rather renews her interest in Edmund, when there’s a chance he’ll be Sir Edmund the estate owner after all.
Persuasion: Captain (then Mr) Wentworth’s relative poverty and lack of immediate prospect of greater wealth is what makes Lady Russell persuade Anne to break off the engagement when they’re young, leading to seven years of heartbreak. Sir Walter’s spendthrift habits land the family in deep debt, and they are forced to rent out the estate, which brings Captain Wentworth back into Anne’s life. Mr Elliot is interested in Anne because she’s the daughter of Sir Walter, and he wants to make sure he gets the title in order to be able to raise more money for himself.
And then there’s Emma. Emma, alone of all of Austen’s heroines, has no need to marry, as all the others do. With them, a husband means a home, economic security for the rest of their lives. Emma has that all on her own, husband not required; and the contrast between her attitude to the world and that of the others is striking. She alone is not hurt by the restricted society she finds herself in, as she has no need to be on the hunt and meet as many men as possible to find someone to marry. She loudly proclaims she will never marry, and means it, too. When Elizabeth turns down Mr Stupid-Clergyman Collins, she not only potentially condemns herself, but perhaps even her sisters and mother, to a life of straightened financial means; when Emma does the same with Mr Obnoxious-Clergyman Elton, she just has her nose put out of joint at his presumption. There are no practical consequences to her choice. Emma messing with Harriet’s life, making her turn down an extremely eligible match for reasons of snobbery, shows her complete lack of comprehension for those whose lives are determined by economic considerations (and Harriet is too naïve to know better herself).
In a sense, Emma is the only one of Austen’s heroines who can afford all those character flaws of hers, who can have a whole story to herself about a person who just needs to grow up, but has no economic imperative to find a spouse – who can genuinely, purely, marry for love. Emma and Mr Knightley freely choose each other, and they are able to do so – none of the others have that same unthinking freedom. For them, it’s either a question of choosing love over wealth (Edward and Elinor come to mind), or of turning down love for the sake of not enough wealth (Willoughby with Marianne; initially, Darcy and Elizabeth, Bingley and Jane, Wentworth and Anne), or of pursuing someone for the sake of their wealth or perceived wealth (Mary Crawford and the Bertrams, John Thorpe and Catherine, etc.).
One could even say that Emma is the only straight-up love story in the Austen canon. All the others are love-and-money stories. And even in Emma, there is no shortage on money-driven sub-plots – Frank Churchill and Jane Fairfax, the Bates’, Harriet Smith…
Love and romance? Not so much. Pounds, shillings and pence, rather.