One of my stepsons asked: “Why have you become so grumpy?” It was a reasonable question, but I would rather he had asked it in private and not with my wife sitting at the end of the table because I knew for sure that she would proffer her own theories.

Sure enough, she suggested that if I drank only at weekends, I would be much nicer to have around. Which made me even grumpier. But it did get me thinking about how to rise above my irritability.

Middle age has something to do with it. You reach a point when there is just so much to be grumpy about. You can’t play tennis half as well as you did 20 years ago. What you see every morning in the mirror is harrowing. You haven’t achieved what you had hoped in your career, and time is slipping through your fingers faster than the grey hairs on your head.

Life has become so difficult. People are so annoying. Why do I have to spell the world “Birmingham” when ringing one of the directory inquiry services? Why are there signs in hospitals begging people not to abuse the staff?

What’s worse is that it seems constant grumpiness pays. According to a German study, you are more likely to be promoted if you are aggressive, single-minded and thoroughly unpleasant. But surely manners maketh the man? So, while sitting outside York station on a delayed, overcrowded train, I concluded that I would try to be really nice and see if that helped. I decided there and then to assume the chairmanship of a new organisation called the Really Nice Movement (RNM), with a responsibility to carry out my duties without rancour or complaint. I would liberate myself from being angry by being good.

The first few days went better than expected. It was a pleasure giving up my seat on the bus, satisfying picking up at least one piece of someone else’s rubbish every day, and a tonic saying good morning to strangers in the lift at work.

Some people think that the best way to deal with anger is to let it out, but I’ve never bought into that strategy. I remember a therapist once wanting me to punch pillows to deal with some buttoned-up repression. I just couldn’t do it with a straight face. As Paul Jenner says in his book Teach Yourself Happiness, it’s no good “venting your anger as if it’s steam escaping from a pressure cooker . . . what you actually need to do is turn off the heat”. That is where choice comes in.

Shortly after launching the RNM, I visited a relative in South London. As she put the kettle on, a neighbour knocked on the door warning that my car was about to receive a parking ticket. I rushed out and told the traffic warden that I was sorry, that I had forgotten to check the signs and was there any chance of avoiding the £50 ticket — please. Pre-RNM days, such restraint would have been out of character. On this occasion? She hit the cancel button — and suggested I move the car or buy a ticket.

Recently, the aforementioned stepson came with me to the Royal Academy, after which he wanted to show me the Abercrombie & Fitch store at the top of Savile Row. As we moved slowly around the exhibition, I kept being distracted by a couple talking at the top of their voices. I felt inclined to hiss: “Sssh!” but whispered quietly: “Would you mind speaking a little more quietly, it’s hard to concentrate.” Bingo. Well, sort of. “Terribly sorry,” the woman boomed. “We are both half deaf.”

On to the absurd Abercrombie & Fitch, where we queued for 30 minutes for the pleasure of walking past two young men stationed just inside the door, stripped to the waist but for teeny-weeny waistcoats. When I asked an assistant where I could find a leather belt, he looked up as if he had better things to do than converse with a podge such as me. Rather than muttering something unpleasant, I cracked what I thought was a clever remark about naked ambition. At least, my stepson thought it funny.

You need resilience when trying to be nice. There are daily setbacks. I find it hard to practise with those to whom I am closest. In fact, I’m not sure if my wife has noticed a difference in me at all. I still sulk when asked to empty the dishwasher. But I get the impression that kindness is in the air in these straitened times. Its day has come. Hop on board. And be nice.

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