Acurious thing happened to me while I was writing my second novel, Affinity. It is set in the 1860s, partly in a women's prison, partly in an upper-middle-class home. It's a rather gothic novel, full of twists and reversals, and for the purposes of theme and plot, there's a foregrounding at certain moments of hands - the drawing of attention, for example, to the strong, possibly sinister, hands of at least two female characters. As I was putting the book together, I was dimly aware that the hands I was describing were recalling some other hands to me; and at last I realised whose those were. They were the scarred and powerful hands of Jaggers' housekeeper, Molly, in Great Expectations - that "wild beast tamed", as Wemmick dubs her.
His phrase is telling: Molly's hands are over-determined in Dickens' text because of the secret to which they gesture - the final secret of the book, the secret of Estella's criminal origins - but I'd always been impressed and unsettled by what seemed to me to be the novel's frankly fetishistic treatment of them, the oddly magnified space they occupy within its narrative economy. Now, writing Affinity, striving after a fetishised and magnified literary effect of my own, I realised they had lodged themselves in my imagination, much as a splinter would; and, like a splinter, they had worked their way to the surface of my mind as part of a creative process over which, it seemed to me, I had disquietingly little control.
But it's one of the defining qualities of great fiction, I think, that its motifs become part of the fabric of one's imaginative life in this way; and it's a feature of the charged experience of reading that those motifs can change their resonance and meaning for us over time. I first began to read classic 19th-century fiction as a teenager, after being introduced to the novels at school; in fact, however - and quite without knowing it - I had become acquainted with some of their major players much earlier than that, through the lurid Friday-night horror films I watched as a child.
It's startling to realise just how many Victorian novels and stories are definitive tales of terror, how many 19th-century characters - Dracula, Dr Jekyll and Mr Hyde, Dorian Gray, Frankenstein, the tormented protagonists of Poe - would come to dominate the imagination and even the vocabulary of 20th- and 21st-century unease. My adult reading of the texts from which those characters emerged has inevitably stripped them of the moistness, the sexiness, the high Hammer colour and gloss lent to them by popular film; but it has discovered them to be, if anything, more genuinely disturbing.
Frankenstein I understand now as, among other things, a parable of traumatised maternity. Dracula reveals itself as a wild invasion narrative, a nightmare vision of the rupturing of the insecure borders of nation and sex. Dr Jekyll and Mr Hyde appeals with awful intimacy to that part of me which knows itself a prey to compulsive behaviour, vulnerable to transformation by the unruliest emotions: desire, envy, jealousy, spite.
In the same way, my tastes in classic fiction more generally have changed as I've grown older. Thomas Hardy I once adored; I now find my gloomy teenage favourites Tess of the d'Urbervilles and Jude the Obscure rather tiresome. Wuthering Heights seemed to me, at 17, to be the definitive statement of romantic love; what I notice when I read it these days are its shocking levels of violence. I like it better, however, for that reason - and I like even more its savage relatives, The Tenant of Wildfell Hall and Jane Eyre.
Only the novels of Dickens, perhaps, continue to overawe me with their originality and linguistic verve just as they did 20 years ago: Great Expectations , in particular, impresses me more deeply with every read, and there are moments in it of which I never grow tired. Jaggers' odd displaying of his housekeeper's hands is one; the return of Magwitch - a magnificent "return of the repressed", in every sense - is another. A third, short, passage I have read so often, I now know it by heart. It comes at the end of Pip's description of his first visit to Satis House: the start of what will prove to be his long and tortured relationship with Miss Havisham and Estella. "That was a memorable day to me," he tells us, "for it made great changes in me." He goes on:
"But, it is the same with any life. Imagine one selected day struck out of it, and think how different its course would have been. Pause you who read this, and think for a moment of the long chain of iron or gold, of thorns or flowers, that would never have bound you, but for the formation of the first link on one memorable day."
I like this passage for many reasons. It is, for one thing, a thoroughly Victorian moment - for a considerable driving force behind much Victorian fiction was the attempt to make sense of modern life precisely by tracing through it chains of causality and connection; and Dickens in particular was supremely good at excavating the submerged and sometimes fatal intimacies between people of different classes and clans. But there is also something here, I think, about the nature of fiction - for what is fiction but the following of imaginary lives along lines of possibility and hazard? - and, more importantly, a sort of enactment of the romance of storytelling itself.
With his direct appeal to the reader, Dickens bursts through the textual membrane of his novel and, paradoxically, draws us closer to the heart of Pip's imaginary emotional life. One hundred and forty years after it was first written, the passage is startling, and fantastically persuasive: I can never read it without doing just as Dickens instructs - nor can I help thinking of the many, many readers who, in the past century and a half, must have lifted their heads from the page before them to brood for a moment, as I do, on the chance encounters, the lost opportunities, the wise or unwise decisions, that have shaped and coloured their lives.
And that, after all, is the final pull of classic fiction: that we come to it as to a community of readers; that it speaks to us in the most intimate and yet the most public of ways, in voices which have retained their extraordinary clarity and pertinence across decades of change.
· Sarah Waters' latest book is Fingersmith (Virago Press), price £12.99.