‘The whole pleasure of marriage’, according to G K Chesterton, ‘is that it is a perpetual crisis.’ He had no time for David Copperfield’s second wife, Agnes – an embodiment of lifeless perfection to be rated far below David’s charming, domestically incompetent first love:

 David Copperfield and Dora quarrelled over the cold mutton; and if they had gone on quarrelling to the end of their lives, they would have gone on loving each other to the end of their lives; it would have been a human marriage. But David Copperfield and Agnes would agree about the cold mutton. And that cold mutton would be very cold.

Jane Austen, no fan of novelistic paragons either, wrote to her niece that ‘pictures of perfection … make me sick & wicked’. One of the many pleasures of John Mullan’s absorbing new book on Austen is how it handles the affectionate contempt of ordinary married life. Take Charles and Mary Musgrove in Persuasion: they bicker endlessly in public, but their quarrels also serve to unite them. From an initial query about how characters address one another, Mullan develops an energetic appreciation of how formality yields to familiarity, and vice versa, throughout the novels. To call someone by their first name might be endearing or slyly impertinent, but formality – where once there was intimacy – can be even more painful. Captain Wentworth’s ‘madam’, in his earliest direct address to Anne Elliot (also in Persuasion), is as chilly as the Copperfields’ mutton. It is only in the agony of Louisa Musgrove’s fall from the Cobb at Lyme Regis that he is finally provoked to cry ‘Anne!’ (even then, he says it to someone else).

What Matters in Jane Austen? is not really an exercise in problem-solving, and it therefore stands in a slightly tangential relationship to its full title. Rather, it pursues Austen’s own celebrated method of working on a ‘little bit (two Inches wide) of Ivory … with so fine a Brush’. Starting