Before you start

This is a short book and you can read it in two or three sittings. It's about one habit, which is thinking something good about a person and keeping it to yourself. Your partner handled a bad phone call well and you noticed. A colleague's slides were the clearest in the meeting and you noticed. Your friend's garden looks better every year, your dad is patient with the grandchildren in a way he never was with you, the woman on the platform has a coat you'd have chosen yourself. You thought all of that, clearly, sometimes in a full sentence, and none of it left your head.

I'm going to argue three things. The first is that keeping it in makes sense from the inside. Saying it feels awkward, you don't know how you'd put it, it might sound like flattery, they probably know anyway, and you're not that sort of person. The second is that nearly every one of those reasons rests on a guess about how the other person will take it, and that guess has been tested, in a lot of experiments over the last few years, and it's wrong in the same direction for almost everyone. People underestimate how good a compliment makes someone feel, overestimate how awkward it'll be, and judge their own wording while the other person is hearing something else entirely. The third is practical. A good thought said out loud has two parts and takes ten seconds, and the best time to say it is within the hour. Chapters 18 to 22 cover how.

This isn't a book about thanking people for what they've done for you. That's a different habit with a different fix, and an earlier book, Thank them now, covers it. This is about the good opinion itself, the one that has nothing to do with you. It isn't a book about flattery at work, and it won't ask you to say anything you don't think. If you don't think it, this book has nothing for you to say.

Two cautions.

If the silence isn't a habit but a fear, if you worry before, during and after most social situations, avoid them where you can, and it's been like that for a long time, the NHS says that's more than shyness and worth seeing a GP about. You can also refer yourself to an NHS talking therapies service. An earlier book, Go anyway, is about turning down invitations out of nerves and may be the one to read first.

And if you've felt low most of the day, most days, for a fortnight or more, and the quiet is part of that, see a GP. This book will keep.

The notes at the back give my sources and their limits. Where I'm giving my own reasoning and not a finding, I'll say so.