WHENEVER OUR FAMILY went on a picnic to some fabulous riverside spot in Australia, my mother would look around and say: “Well, the blacks must have done all right for themselves here.” We’d glance around, agree, move on.

Under the surface of her words, not quite audible, were two ideas – our place once belonged to others, and they were gone.

And under the surface was where those ideas stayed. It wasn’t comfortable to look at them too clearly. As one Australian anthropologist put it: “A secret river of blood flows through Australian history: the story of our dealings with the Aboriginal people.” That river was the other one with us on those picnics, but it remained secret.

There it might have stayed for me, if I hadn’t embarked on two journeys. One was the journey of psychoanalysis. The other was the writing of The Secret River, my novel about my great-great-great grandfather, one of those early Australian settlers responsible for the “blacks” being “gone”.

I am startled at how much they had in common. Both were efforts to bring to consciousness things buried. Both used the same tools: dreams, free association, and trust in a process that for a long time seemed to go nowhere.

I began the research in a professional, workmanlike spirit: let’s find the facts, I thought briskly, and shape them into a book. I researched my ancestor’s life (he was a Thames lighterman who stole a load of timber and was transported to Australia in 1806) and gathered information about the whole sorry story of black-white encounters on the frontier.

The research took me into some well-hidden dark places. Like most nations, Australia is inclined to clean up its past.

But when the dutiful researcher went off-duty, something more began to appear. At first it happened by accident: I decided to spend the night alone in the Bush to simulate my characters’ world.

It was too dark to take notes, and the Bush at night is so huge, so full of its own wordless life, that no notes seem adequate. For once the conscientious researcher just sat. Just sitting made a space in which the voice of the busy thinking mind had to fall silent. Into that silence came the voice of the unconscious, speaking the language of feeling, intuition and synthesising leaps of the imagination. That night the surface parted and let me hear things about the place and its original people that I’d never let myself hear before. It was the start of finding the story I was trying to tell.

And I’d been there before, I realised. In my analyst’s room, there had been long silences in which nothing seemed to be happening. There was never a single eureka moment of breakthrough. Just that the surface shifted, a new kind of understanding took place, and nothing was the same.

Before I was a writer (and long before analysis), I thought writers knew in advance what their books were about. “Know what you want to say” is the advice often given to beginning writers.

My first published novel, Lilian’s Story, was written without a plan, working by free association and wild speculations. Writing it was a daily exercise in suspending judgment, listening for a voice it was hard to hear. It prepared me, in a crude homemade way, for sitting with those silences in my analyst’s room.

In writing, as with understanding the psyche, it seems that the more you think, the less you know. There are things we don’t want to have to look at, and the thinking mind can be relied on to cast clever veil after clever veil in front of them.

But writers are in the business of getting behind those veils. Kafka said that “a book should serve as an axe for the frozen sea within us”. “Us” means the reader, of course. What I discovered in my twin journeys is that it means the writer too.

Kate Grenville’s Searching for the Secret River is published by Canongate, £8.99,

Buy the book here for the offer price of £8.50 (inc p&p)

On the couch

Kate Grenville will talk to the analyst Margot Waddell about the creative process and the mysteries of her family history at the Institute of Psychoanalysis, 112a Shirland Road, London W9, on July 12 at 8.30pm, as part of Connecting Conversations, a series that links psychoanalysis and other disciplines including literature and the arts: connectingconversations.org Tickets £12/£6 concessions: www.thebloomsbury.com or from 020-7388 8822 (booking fee applies)

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