When you are famous, working for charity has become almost de rigueur, and while it can be stunningly effective (witness Brad Pitt in New Orleans) it can also be profoundly off-putting. That is perhaps why I’ve tried to work out a few helpful hints for myself.

I’ve only just started to understand that being a celebrity means dealing with this large projection that I lug around with me. It’s a bit like being on a promenade, pulling around a great big bunch of multicoloured balloons — something inflated and distracting that follows me wherever I go. So, if I happen to be shouting about HIV or poverty or torture, I cannot blame people for asking themselves why I’m shouting about that when I’m clearly selling balloons. And of course, on the whole, people prefer balloons to poverty, so a public profile may guarantee me attention, but it doesn’t guarantee that anyone will hear what I’m saying. Far from it.

A good start is to learn as much as you can about a subject and then work out how useful you can actually be. Being practical about it is vital. This is advice that I would tender to anyone interested in activism of any kind: ask yourself why you want to do it and remember that self-righteousness irritates rather than inspires.

Part of the problem lies in semantics. Words such as “charity”, “cause”, “development”, “human rights” and “activism” can all become skewed with misuse. At best, overuse renders them banal. But at worst they become counterproductive. Say “human rights activist” and increasing numbers of people will just slam their hands over their ears. There is causeweariness even before you prefix “human rights activist” with that extra soul-sapping tag “celebrity”.

The question I dread most is: “What’s your favourite charity?” You might as well ask: “What’s your favourite war zone?” To talk about charity in this way compartmentalises it, separates it from the day-to-day stuff of life. Yet what we are talking about is something fundamentally life-enhancing; engaging with people whose lives are often much more challenging than yours, gaining understanding of what they may have been through and sometimes actually being able to contribute. At various points in my life there have been many issues that I have learnt about and worked on. Whether it’s domestic violence, poverty, Aids, the environment or the plight of refugees, I firmly believe that all these causes are connected, connected to our darkness and connected to the human condition. But when we think about “causes” we tend to think about something that has no direct relevance to our day-to-day lives.

Thinking, and listening, and sometimes acting to help other people who may have survived and endured terrible situations can be (and this sounds very selfish, but it’s true) a fascinating practical investigation into how one can achieve some kind of progress in the business of being human. It takes only a tiny twist of consciousness to make the leap from a save-the-world complex to something much more honest, fulfilling and achievable.

I was in my twenties when I first encountered the children of Víctor Jara, the musician and theatre director, who was murdered during the coup in Chile in 1973. They came to London and were exactly the same age as my sister and me. The parallel lives of those girls flung a very resonant, life-changing light over my life. What struck me was that people could be walking side by side and yet have experienced completely alternate universes. I might be being picked up by my dad after school while they were remembering a dad shot by soldiers in the pay of the Government. It helped me to understand that the world was more complicated than I thought and that things I took for granted, such as the rule of law, were not immutable. That we didn’t live in different universes; like it or not, we lived in the same one.

Later on I met survivors of torture from Chile and Argentina and, while horrified by what they had experienced, I was fascinated by their mechanisms of survival. It was then that I started to understand how the survivor contributes to the development of human character — how the stories of those who have endured inhumanity can enrich us in the same way that listening to poetry can enrich us.

Helen Bamber, whom I first met in my twenties, once told me that victims of torture have their voice taken away from them twice over. During incarceration and torture, they are deprived of a voice. Then, if they survive, often nobody wants to hear about what has happened to them. It’s too disturbing. Thus, they lose their voices for a second time in the very place they may have expected to be heard. Some of them, having survived torture, cannot survive this rejection. What she has always said is that the hardest stories to listen to are often the most rewarding stories to hear. If you are interested in helping anyone, the simple act of listening is your first proper contribution.

She also pointed this out: human rights are no more set and reliable than the trees in the rainforest. If someone wants to cut them down and has the power to cut them down, they’re gone in an instant. They only remain solid if every generation works to keep them alive and that means a lot of work and a lot of understanding.

My experience is that it is the sort of work that makes you happy and keeps you alive. But I’m still selling those balloons.

Emma Thompson was talking to Luke Leitch The Art of Survival: Helen Bamber Foundation Art Auction is at Maddox Arts, 52 Brook Street, London W1, on Thurs, 6-8pm. The exhibition is on May 5-7 (www.theartofsurvival.org)

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