Before you start

This is a short book. You can read it in two or three evenings, and I'd be pleased if you stopped each time when you got tired.

It's about one habit. You've been tired since about ten o'clock. You know you have to be up at half past six. Nothing is keeping you up, and there's no deadline or crying baby. And you stay where you are until midnight or later, because this is the first moment all day that nobody has wanted anything from you. Going to bed feels like handing the last of the day back.

I'm not going to lecture you about sleep. You already know you should get more of it, and knowing hasn't helped. I'm also not going to tell you that wanting time to yourself is self-indulgent. I think it's a real need, and much of this book is about taking it more seriously than you do now.

What I'll argue is this. The need for time of your own is sound. Taking it out of your sleep is a poor way of meeting it, because it gives you that time in the worst condition it could possibly come in and charges you for it the next day. There are better places to find it, and chapter 11 goes looking for them.

Three cautions before we start.

This book is for people who could sleep if they went to bed. If you go to bed and lie awake for a long time, or wake in the night and can't get back to sleep, that's insomnia, which is a different problem. Spending longer in bed isn't how insomnia is usually treated, so please don't take this book's advice as aimed at you. Some people stay up late precisely because they've learned that bed means lying awake. If that's you, a GP is the place to start, and chapter 14 says more.

The second caution is about tiredness that sleep doesn't fix. Suppose you get a decent number of hours and still feel very tired every day. That's worth a GP appointment, especially if someone has told you that you snore loudly or seem to stop breathing in your sleep. There are medical causes of tiredness that no change of bedtime will touch.

The third is about circumstances. If you work nights or rotating shifts, or you have a baby who wakes, or you care for someone through the night, then your sleep is short for reasons outside you. This book is about the hours that were yours to sleep in and that you spent on the sofa. It has nothing to say against people whose hours were taken.

If you take medication for sleep, mood or anything else, nothing here is a reason to stop it or change the dose.

The middle chapters each take one belief that keeps people up. "It's the only time that's mine." "I'm fine on six hours." "I'll catch up at the weekend." Each is partly true, and I'll try to give it its due before I argue with it. The notes at the back give the studies I've relied on and their limits. The rest is my own reasoning, and I'll say so where it matters.