In bed with Susan de Muth: At night I separate fax from fantasy: Terry Pratchett

I NEVER dream about my own work, nor does the fantasy world of my books overlap with my dreaming. I have to be very careful to be in control of my imagination rather than live in it - otherwise I'd be a candidate for the white canvas jacket with the optional long sleeves.

I once got somebody else's dream. I was in some kind of weird machine that was producing a revolutionary new form of energy and a little man was patiently explaining everything to me in meticulous detail. I didn't understand a word and I thought, 'This is the big revelation after months of research and I've got it by mistake instead of some poor bugger at Cambridge'.

I work until the day seems to reach a natural conclusion - sometimes not before 2am. After dark, time becomes my own again. Nobody's going to phone me or send me faxes and that gives me a second lease of life. At night I refine what I've written during the day with some background noise from the radio - usually classical music. I always stop at a very exciting moment so that I've got a treat to look forward to when I start again in the morning.

Night is also an extremely good time for making energetic plans for tomorrow - because you don't actually have to do it. If you start thinking 'I'm going to cut the lawn' at three o'clock in the afternoon a little voice will always say to you 'well why don't you do it now?'

Before I go to bed I have to double check that everything I've written is saved on the word processor. That's the modern neurotic for you. I once lost a whole novel late at night when I kept pressing 'yes' to questions like 'do you really want to do something as bloody stupid as format your entire hard disk?'

I fall asleep the minute my head touches the pillow. I've got the sandman in a forthcoming book - only this one doesn't sprinkle sand around, he hits people with the whole bag] That's how sleep is for me. In winter I tend to be bear-like and hibernate: I don't go out and I sleep much more. Those Tupperware skies weigh heavily on me. Lyn and I ease ourselves kindly into each new day and the slow process from horizontal to vertical can take up to half an hour, with many cups of tea and lying down for another five minutes. I used to bustle down to fetch the post but there's so much of it these days that Lyn insists on filleting it first.

Since my books have become best sellers I've been away on tour a lot. Conjugal rites at such times consist of handing over a suitcase of dirty washing and picking up a new one on my very occasional free days. At other times though, Lyn sees more of me than most wives see their husbands - I'm always popping down for a cup of coffee and a chat.

I start work the minute I manage to get up - I like to make a dent on the day by getting an hour or so in before breakfast. Morning is a clear time; I often wake up with problems I'd had squiggling around in my head the night before somehow sorted out. The brain does a lot of work while you sleep, filing and tidying things up. I don't believe that dreams are generally anything more than random images thrown out as it goes about this business, but once every six weeks or so I get a real humdinger. These unnervingly convincing experiences often involve popping up in other people's relationships and affect me way into the next day.

The other night I had a dream that took place in Victorian dress. A young lady was miffed with the character I was playing because he'd promised to marry her and hadn't. I felt vaguely ashamed all the next morning . . . then by about 10 o'clock I had to say to myself, 'What are you doing? Why are you thinking like this. This is 1993]' I fight like hell against supernatural explanations but it's undeniably quite strange.

The most meaningful nocturnal experience I've ever had was when I was a boy. I was sitting on a fence, looking up at the stars and I suddenly thought 'actually, technically, in terms of the universe, I'm just as much looking down at the stars as up'. I nearly fell off the fence and I suppose that's when I realised that there is always more than one way of looking at 'reality'.

Terry Pratchett is a best-selling fantasy writer. He lives in a cottage in Somerset with his wife, Lyn, and daughter, Rhianna.

Terry Pratchett's latest book, 'Men At Arms', is published by Victor Gollancz, ( pounds 14.99).

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