Suppose you warn your brother that if he doesn’t get his car fixed it will break down. He doesn’t do it and, sure enough, it breaks down late at night in the middle of nowhere. Or maybe you advised your friend to leave their job and they didn’t listen. Now the firm is going into receivership. Or perhaps your colleague didn’t believe you when you said that the company was relocating – and they’ve just found out you were right. Now, how are you going to respond to all these things, when it turns out you were right all along?

If you’re thinking the answer is to say, ‘told you so’ then go to the back of the class and stay in after lessons. You can write out 100 times ‘I must not say “I told you so”’. But, of course, you’re a Rules player, so you won’t have been thinking any such thing, will you?

If you’re following the last Rule, and not giving anyone advice, this Rule is much easier to stick to. You may privately have foreseen the outcome, but if you resisted proffering advice, well done, and now there’s no temptation to say ‘I told you so’.

So what’s wrong with saying it? Well, the only times the phrase is ever used is when something bad has happened to someone and you predicted it. Or when something good has happened that you predicted and they failed to. So what the expression actually means is, ‘Look! I’m right and you’re wrong. See?’

Now just explain to me how this is ever a helpful, supportive, kind or considerate thing to say. The fact it’s true is neither here nor there. The fact is you’re talking to someone who is at best wrong, and at worst also in a hole because of it, and choosing to rub their nose in that fact. Is that Rules behaviour? No it isn’t.

When was the last time someone said ‘told you so’ to you, and you felt grateful to them, appreciative that they’d drawn your attention to how wrong you’d been in contrast to their own rightness? When did hearing those words cause a warm feeling of love and thankfulness to flow through your veins?

Never, is my guess. Because no one wants to hear it. And I don’t blame them. So next time you’re right and someone else is wrong, just button it. You know you were right, and that will have to be enough.