My charming, beautiful, articulate and witty daughter-in-law, Catherine Ostler, who edits Tatler, had a sneak preview of my new novel, The Misogynist, and told me that it belonged to the genre "Git Lit" — at the other opposite end of the spectrum from "chicklit". She was too polite, or too mindful of the importance of irenic relations within a family, to call it a "gaga saga". 

The publishers are happy with this categorisation. They put the novel's protagonist, Geoffrey Jomier, in the company of other "grumpy old men", no doubt hoping to entice the admirers of Kingsley Amis's The Old Devils, which won the Booker Prize in 1986, or those who have enjoyed the recent novels of Philip Roth. Or Justin Cartwright. Or Ian McEwan's Solar? 

 
How do older men fill their time? "The Connoisseurs" by Thomas Rowlandson, 1799 

Looking back to the classics, what works were the precursors of git lit? Prince Bolkonsky and General Kutuzov in War and Peace might properly be described as grumpy old gits but they are not major characters in the novel. How old was Bazarov senior in Fathers and Sons? There is the Prince of Salina in Lampedusa's The Leopard who acts old but was only 52. And Brás Cubas in that classic of ironic pessimism by the Brazilian Machado de Assis, Memórias Póstumas de Brás Cubas: the narrator here was not just old, he was dead.

However, these are exceptions to the rule. In the 19th century, men died at a younger age than they do now, and so there was not much to record about sixty-something-year-olds. And since novels were mainly bought by young women, the older men tend to be cuddly old dads like Mr Bennet in Pride and Prejudice, or ghastly pedants like Casaubon in Middlemarch to compare and contrast unfavourably with romantic juvenile leads like Darcy or Will Ladislaw who would appeal to the said novel-buying young women. As Jomier notes in The Misogynist, 19th-century novelists knew which side their bread was buttered and so, when it comes to women, "portray lovely, clever, witty, charming heroines and spin elaborate narratives around what au fond is their quest for insemination".

Perceptive critics may see my story about the late-life love affair of a divorced barrister living on the wrong side of Shepherd's Bush as an aid to the sociological understanding of a new phenomenon — our ageing population. We have never been here before. Jomier, spending Christmas in Venice with Judith, his new love, reads Svevo's Senilità — As a Man Grows Older — written across the lagoon in Trieste and notes that Svevo's older man was only in his forties. Thanks to all those well-known factors — healthier diet, medical advances, Viagra — a man's life may now continue for years, even decades after retirement. What is he meant to do to fill the time? Read? Travel? Garden? Fiddle with an iPad? Fall in love?