For me this is a really hard one. I do love to have a good shout. I came from a big robust family where shouting was a way of life and the only way to get yourself heard, get any attention or to make a point. Dysfunctional? Yes. Noisy? Yes. Helpful? Probably not.

One of my sons has inherited the shouting gene and he is very good at it. The temptation is to join in. Luckily this Rule is be the last to raise your voice, so I do have a get-out clause. If he shouts first, I’m allowed to shout back. But I do try really hard not to. For me, shouting in any form is a bad thing, a sign that I have lost control, lost the argument. The son of a vicar once saw his father’s sermon notes and in the margin he had pencilled, ‘Shout here, argument weak’. I think this just about sums it all up.

But I have shouted at various times and invariably I regret each and every occasion. I know I’ve dined out on the time I was very shouty in a well-known high street electrical chain over a damaged DVD player. At that time I did get my own way, but the reality is that it was a bad thing and deep down I’m quite ashamed of myself.

So what do you do if you too have inherited the shouty gene like me? I find that I have to walk away to stop the inevitable decline into shouting in a challenging situation. Tough one, especially if you know you’re right. There are so many things that make us shout, so many situations where we feel that a judicious loss of temper will get us our own way. But we are dealing with real live human beings who have their own feelings, and shouting is not justified – even if they start it first.

There are two situations where people lose their temper – justified and manipulative. The first is where you run over their foot with your car and refuse to apologize or acknowledge you have done anything wrong. In this situation they are allowed to shout. The second situation is where people use anger to get their own way – a sort of emotional blackmail. You are allowed to ignore them, or to be assertive to control the situation. You are not allowed to shout back.

I know, I know, there are all sorts of situations where shouting seems appropriate – the dog is stealing the Sunday dinner; the kids won’t tidy their room; your computer has crashed again and the repair department won’t fix it quickly enough; the local hooligans are adorning your wall, again; after going through the umpteen options over and over again you fail to get through to the switchboard after holding for 20 minutes; they put up the closed sign just as you get to the counter; someone is clearly being stupid and deliberately choosing to misunderstand you.

And on and on and on. But if you take this Rule as a simple ‘I don’t do shouting’, it becomes an easy benchmark to stick to. You get known as someone who is incredibly calm no matter what is happening. Calm people get trusted. Calm people get relied on. Calm people get looked up to and given responsibility. Calm people last longer.