There's a stereotype of the weary writer, struggling to meet a deadline, hunched over a typewriter - or, these days, a screen - working into the small hours while the coffee cups pile up like snowdrifts.
It's a beguiling image, and one that probably has some truth in it, especially for journalists and other writers who have such a high turnover rate that they're hardly ever not running up against a deadline.
It combines, somehow, a sense of professionalism - of being a "real" writer, in demand even! - with the romantic ideal of a bohemian poet, starving to death in a lonely, moon-washed garret, as they pen their deathless verses with ink from a frozen inkwell.
But the thing about poets starving to death in lonely garrets, the important, the most important thing, the defining feature, you might, say of their particular profession, is that however good their poetry is, they still end up dead.
And honestly, their poetry might have been a lot better if they'd had a few more meals, and a warm bed to sleep in, instead of a short, beautifully tragic life full of the first-hand experience of loss and woe that somehow never quite translates itself to the page.
Human beings need sleep to function properly: without it, all manner of things go wrong.
Take my eldest daughter, for example. She got to bed appallingly late last Friday and, after a terrible night's sleep, was still completely shattered when she got up, early on Saturday morning, to go to her first ballet class of the day.
It was suggested that perhaps she should miss this class, just this once, as she was clearly too tired to concentrate. She refused: a good dancer, she claimed, did not let a little thing like fatigue hold her back.
So we got on the bus, and then we got on the next bus, and then, just a little after we got off the last bus to head in to her class, she admitted that perhaps she was a little too tired to concentrate properly, and perhaps, after all, she should have stayed in bed. But it was too late to do that now, so in she went to class, where she staggered through all the exercises and retained basically nothing of what she was taught.
Meanwhile: because she had insisted on going to class I had also had to wake up and get out of bed; and because I had got out of bed my husband woke up; and since he was up, and had time on his hands, he decided to fix the headboard on our bed, which is a two person job, but which he had to tackle solo because I was on a bus, taking a determined somnambulist to her ill-advised ballet class.
So because he decided to tackle a two-person task single-handed he dropped the headboard on his knee, and because he'd dropped a whacking great lump of wood on his knee he was incapable of picking her up to take her to the remaining four classes she was supposed to have that day. And also he was in quite a lot of pain.
Although at least some of that pain was down to him being a blithering idiot who refused to wait until I was there to fix the headboard with him.
She gets it from him, you know.
Anyway, all of this pain, and suffering could have been avoided if she had just had a lie-in for once.
Admittedly none of this has anything to do with writing, but I know that the analogy is sound because while she was stumbling, half-awake through her class, I was writing six hundred fairly decent words in the coffee shop down the road, next to my friend Colette, who was, in fact, on a deadline, but who has far too much sense to sit up all night writing when she's already been up all day. Six hundred words isn't much, I realise, but you have to understand that a good part of my process involves banging my head on the table, howling into the void, and staring bleakly into nothingness in the hope that I might find the word that I am looking for inexplicably written there. All that takes time, you know.
So six hundred words in just under an hour and a half is honestly pretty good. It's even better, though, when you realise that these were the first words I had written in about three months that I was even vaguely happy with. I'm probably going to cut them all, but that isn't the point.
My point, which I promise I am finally getting to, is that I have spent the last three months getting very little sleep and, in consequence, writing almost nothing worth reading.
That probably goes for these blog posts, too, come to think of it. Sorry about that.
The thing is that we got a new mattress. And the new mattress was about as soft, yielding and comfortable as a slab of granite.
We mentioned this to the mattress company, who sent us a foam mattress-topper, which meant that our mattress became at least as comfortable as a slab of granite topped with a thin layer of easily compressed foam. Naturally this was not a practical solution to our problems, so we looked for a new new mattress and, in the meantime, piled every spare duvet we could find on top of the old new mattress, rendering it as comfortable as a slab of granite covered with several duvets, and allowing us to at least sort of sleep. It was not a huge success.
We slept, but only barely. Eventually we found a new new mattress, and, in the week between returning the old new mattress and installing the new new mattress, we slept better on a cheap airbed than we had on a proper bed in all the past ninety nights put together.
And then we installed the new new mattress, and everything was lovely.
But, to return to the point I promised I was making: during those past ninety nights and the days that went with them, I had written nothing but a congealed mass of badly-sprung words and half-formed ideas, tied together with square brackets full of confusion and awkward phrasing.
The six hundred words I scribbled in a coffee-shop, after a single good night's sleep were the first decent thing I'd written in about a quarter of a year. Of course not every writer is the same. Some probably do quite well on sleepless nights and coffee. Some probably thrive on it. There are famous writers, after all, who did their best work hopped up to the gills on unspeakable combinations of pills and alcohol that are very definitely not supposed to be combined.
So if you enjoy writing while your eyelids sag and the shadows beneath them render you more and yet more panda-like, more power to you: may the words be as copious as shadows in your poky, darkened room, and may your harsh, bitter coffee be an ever-present balm to the soul.
But for the rest of us: remember that you don't have to sit up all night writing if you don't want to. Deadlines are deadlines, it's true, and sometimes these things really can't be helped, but extensions are also extensions, and quite often they can. Sleep when you need to, take a break if you need it, look after your mind and body both and your writing will be the better for it. And for the pedant who's been aching this time to correct me, or for the kind, worried soul who thinks that maybe I'm still a little over-tired, and perhaps I just didn't notice: no. That title is not a mistake. I have a comfortable mattress at last, and I'm damned well going to use it. You can wake me up next Tuesday: I'm going back to bed.