But I confess that when I opened the novel last week and was greeted by its famous first sentence, which everybody, including myself, claims to know by heart, I wasn't quite sure when, or even whether, I had read the book before. I crushed my bolshie resistance to the "canonical", sharpened a pencil and sat down at the kitchen table.

Austen blasts off with a fast-moving passage of dialogue between Mr and Mrs Bennet that lays out their relationship – her garrulous stupidity, his dry, self-protective "teazing" – and the central matter of the tale: the business of getting their five daughters married. My god, Mrs Bennet is appalling. Every time her husband opens his mouth he takes revenge on her; today he is punishing her by means of a sadistic reticence about Mr Bingley, a wealthy, single young gentleman who has moved into their neighbourhood and set it abuzz.

The Bennets throw a dinner party for Bingley, who brings along his best friend, Mr Darcy. Handsome. Ten thousand a year. Large estate in Derbyshire. But wait. Darcy has a forbidding countenance. Elizabeth overhears him make a disobliging comment on her person and on the company. He's the most disagreeable man in the world, "ate up with pride". Everybody hopes that he will never come there again.

NOBODY in this society (except the soldiers) has to do anything that would nowadays be thought of as work, though some of the less-brilliant among them have made their money "in trade", or "in the north". They drive about to parties and dances, or take tea in each others' pleasant dwellings, or go for long, muddy walks.

For a while, I kept expecting Austen to tell me what things looked like. Then I remembered that Joseph Conrad was exasperated by her novels: he couldn't see anything and it drove him crazy. I accepted that the appearance of things is not what she cares about, though Elizabeth's "weary ancles and dirty stockings", and later an army camp with "its tents stretched forth in beauteous uniformity of lines", gave me a furtive visual thrill.

Elizabeth and her adorable elder sister, Jane, who is plainly going to wind up marrying Bingley, no matter what obstacles Austen might throw in their path, have cornered the brains, sweetness and decency of their family. Anyone who's ever read a book can see that Darcy will have to be brought to heel as much by the rules of narrative as by Elizabeth's admirable character and rigorous self-command.

Yet a source of chaos is needed to disrupt and delay the graceful blossoming of the plot. Austen has it covered. Younger sisters three and four, Lydia and Kitty, are "vain, ignorant, idle and uncontrouled". A militia regiment arrives in the neighbourhood. The place swarms with officers. A highly appealing fellow by the name of Wickham strolls onto the stage, eclipsing (even for Elizabeth) the snobbish Darcy.

I was no Janeite, but I knew Wickham's type. His charm is too rapid and shallow, too easy, for a heroine of Elizabeth's calibre. She falls for it, though, and takes at face value his tales of Darcy's treacherous dealings.

I lowered the blinds against the heat, unplugged the phone and moved operations to my sopha, where, dispos'd among charmingly group'd cushions, I settled in for the duration.

IN ORDER to keep my eye on how Austen was actually doing things, I was having to work hard against the seduction of her endlessly modulating, psychologically piercing narrative voice, her striding mastery of the free indirect mode.

"To interrupt a silence which might make him fancy her affected by what had passed . . . "

"Their indifference restored Elizabeth to the enjoyment of all her original dislike."

"It was a wonderful instance of advice being given without being resented."

So it came as a surprise to me that Mr Darcy makes Elizabeth his first proposal – which she repels in a scene of breathtaking muscle and spark – on page 210. Wasn't this rather premature? Had she hung out the flags of love too soon? I tilted the book and examined its profile. Exactly halfway! The cunning minx! She was going to make me wait another 218 pages for a resolution! Torn between despair and violent longing, I was obliged to rise from my sopha and take a turn around the drawing room.

Darcy, rejected and mortally offended, lurks in the garden. He emerges from behind a hedge and gives Elizabeth a letter, an elegantly written disclosure of Wickham's "vicious propensities", his "life of idleness and dissipation", and his corrupt behaviour towards Darcy's innocent younger sister. Elizabeth is thrown back upon herself in a most bracing manner.

Here Austen gives us five enthralling pages of Elizabeth thinking. She reasons like a lawyer, or, rather, like a jury, weighing up evidence, assertion, argument. She turns on herself the cool, unsparing light of her moral intelligence, and finds herself wanting.

Yet Austen never lets us, or Elizabeth, off the hook of her own detached wit: "Not a day went by without a solitary walk, in which she might indulge in all the delight of unpleasant recollections." And in the sobering facts and reasoning that stream through this chapter, in which Elizabeth is forced to acknowledge to herself the ghastliness of her own family and the rightness of Darcy's dislike of them, I almost missed the pained and gentle last line of his farewell letter: "I will only add, God bless you."

LYDIA Bennet, at 16, is a piece of trash. She earns our contempt not by eloping, but by jeering at a social inferior, an innocent waiter who has just served her: "But he is such an ugly fellow! I never saw such a long chin in my life."

We don't need Austen to explain how Lydia's coarse behaviour risks destroying her sisters' marriageability. A line of dominoes will topple whispering to the ground if her narcissism is not reined in. And Austen does not scruple to sheet home Lydia's awfulness to her ill-matched parents. Instead of putting up a sturdy resistance to his wife's idiotic indulgence, Mr Bennet has retired to his study and his sarcasm, and left his younger daughters to their own devices.

In a letter of shattering selfishness that Lydia dashes off to her married friend, merrily telling her that she and Wickham have run away, she sends a message to a servant: "I wish you would tell Sally to mend a great slit in my worked muslin gown."

If the story had not by now become so dark, this joltingly sexual image would have made me burst out laughing. What can mend the great slit that Lydia has torn in the story? While Darcy, using all his wealth and power behind the scenes, is picking up the pieces left by her heedless rampage, Austen will not allow Lydia to redeem herself. She pushes the girl's narcissism so far that it becomes grotesque, hilarious; yet I laughed with heart in mouth.

I writhed with joy on my sopha when Elizabeth takes it right up to Mr Darcy's aunt, the monstrous Lady de Bourgh, who intends her sickly daughter to marry Darcy. Under their parasols, in the copse, the two women go several savage rounds. The domineering old hag fails to lay a glove on our nimble, steely heroine.

But around page 387 I started to feel restless. All the loose ends were being tidied up and put away. It was a wrap. Wouldn't any ragged threads be left hanging, for me to be going on with?

And here she comes again, the relentless Lydia. Three pages before the end she writes the newly married Elizabeth a truly outrageous letter: "I am sure Wickham would like a place at court very much ... Any place would do, of about three or four hundred a year; but however, do not speak to Mr Darcy about it, if you had rather not. Your's, &c."

I sprang off my sopha at last, strode to the freezer for a slug of Absolut, and raised my glass in silent respect. A toast to the Empress, Jane Austen. God bless Elizabeth Bennet and Mr Darcy, and the current of deep, warm erotic attraction that flows between them. And long live the Lydias of this world, the slack molls who provide the grit in the engine of the marriage plot; for without them it would run so smoothly that the rest of us would fall into despair.