Here are four people who've done just that. They believe all these things that we take for granted are poisonous to society, detrimental to our health and are killing the planet.

They're not your typical penniless tree-huggers. They are entrepreneurs, teachers, agriculturalists and designers. They are rational people with their minds on the bigger picture. They walk among us and they are changing the landscape of our country . . . one free thought at a time.

Whole world in your hands Jan Golden, founder of Tai Chi Ireland, has given up drinking tap water; he rarely drinks anything that he hasn't distilled himself. He runs the tai chi school on Baggot Street, Dublin (www. taichi-ireland. com) and it's from there that he teaches his students about their bodies, and their health.

When it comes to water, Golden believes you have to be very careful. "Water is the element in which all of your body's essential chemical reactions take place: the protein synthesis, the blood supply, the digestion, the movement of your hormones. The water you drink therefore should be of a high quality."

Having a built-in filter is not practical for Golden, so after he distils his tap water he treats it using a device that looks like a jug with a spoon stuck to the inside lid. The water is spun so fast that it causes a vortex. This vortex is said to stimulate the water, causing an effect its makers say is the "closest thing to a fresh mountain spring".

What sets the water that undergoes this process apart from bottled spring water involves a theory based on the studies of Austrian scientist Viktor Schauberger, says Golden. The 'implosion theory' Schauberger developed has been continually researched and new findings are emerging all the time.

The main results so far are that "water that has been stimulated is closer to fresh running water in molecular structure.

This water is better for us because it more closely resembles the water that surrounds our cells, when we are born. The water surrounding our cells when we are born is charged with electromagnetic energy and is as toxin free as its going to get."

When our cells lose this water, it is not easily replaced. And dehydration of this kind is now said to cause aging.

Golden treats all his water with this 'energiser'. And he has developed a timeless, healthy look about him.

In restaurants he only drinks bottled water, with no ice. At home he eats organic wherever possible and when he does go out for food he'll chose seafood. To the onlooker, Golden's lifestyle might seem complicated, but he stresses that anyone can do it, once they see it through. "It's all about having the will and the perseverance."

Golden believes the personal, internal environment and a larger ecological worldview are one and the same. "The first step to changing the external environment is to change the internal environment, change your dietary habits, eat whole foods. I try to live ethically because, in addition to the ecologist movement, within a lot of the meditation I practise there is a respect for the earth.

"People think of the environment as a political issue, as something outside of themselves. In tai chi, what I try to teach people is to respect there own internal environment because they are the environment. Once they respect that, the rest will follow."

But starting off isn't easy. It's been a long hard process for Golden, and people often resist the changes. That's why, as Golden says himself, "you can't force this stuff down people's throats. They'll only change if they want to."

Changing the channel Kaethe Burt-O'Dea is a product designer by trade. She lives in Stoneybatter with her youngest daughter. Burt-O'Dea has miraculously managed to raise her family without television.

"Children always find something to do, and if there is no television they find something else to do quicker!" she says.

That sounds like a big ordeal. But the proof is in Burt-O'Dea's daughter. She is not only energetic and enthusiastic about all sorts of other extra-curricular activities, but she is perhaps a little better educated than the average 12-year old.

Burt-O'Dea feels that TV isn't the be all and end all of quality media. "We all suffer from information overload. I am very selective about how I source my news. I get a paper once a week, usually Saturday, to get a view of the week, and listen to radio news. I subscribe to email news highlights and scan them every morning."

And when it comes to home entertainment, "TV saps time, particularly when you are tired and have very little resistance.

I would rather spend that time getting out, reading or working on creative projects."

"I resent the materialistic lifestyle and the shallow values and culture that are dominant in TV programming. It is relentless, you cannot escape the corporate view that all we want is to consume. I am aware of how the rest of the world lives and simply refuse to support a communication medium that promotes destructive disregard of our global responsibility."

Burt-O'Dea says most people are envious that she has managed to accomplish life without television with all the accompanying stress involved arguing over who has the remote. Recently, she attended a conflict resolution workshop in her daughter's school, which only confirmed her feelings towards the box. "When the children were asked what causes conflict in their homes, TV was the first thing mentioned."

Burt-O'Dea would encourage everyone to give up television.

"Give up TV and spend the extra time with real people! Join or start some form of group activity, preferably within your local community. The most sustainable changes start gradually and develop slowly. We hardly know our neighbours any more and we all have so much to offer each other. Knowing, understanding, and supporting the people in our own community brings immediate benefits and is the best training for tackling the daunting barrage of global issues we are facing today."

Eat green, think green Patrick Finnegan, in his 50s, is the co-ordinator of Grian, and among other things writes Enfo sheets on energy awareness. He has been banging his head against a brick wall (metaphorically that is) for the past 30 years. This is because Patrick has given up fossil fuels. (And if that's not enough, he's a vegetarian too. ) As Finnegan says himself, climate change and vegetarianism are inextricably linked. "As it turns out, vegetarianism is one of the best solutions to climate change. Protein from meat requires 10 times the land area, energy and water as vegetable protein. The more people who swapped to vegetable protein, the less energy and water we would use.

"Ninety per cent of agricultural land could be freed up for energy crops and/or trees to soak up carbon."

An expert in agriculture and energy, Finnegan decided to give up unnecessary energy consumption years ago. His turning point was in 1972, when he was studying in UCD.

"I realised we were being taught how to do agriculture and economics in a completely unsustainable large-scale manner that took no account of environmental impact."

Now Finnegan has learned to limit his impact on the environment. "I have never had a car. I use public transport, my bike, trains and my feet. I don't have a washing machine. I use a launderette instead, and use only biodegradable washing powder when I'm there. I don't have a toaster, microwave, freezer, or TV either. But I do have three guitars, which is enough for anybody!"

When he can, Finnegan tries to convert the masses, household by household. He gets immense satisfaction "every time I convert a completely non-environmental, middle-class Dublin household to recycling and compost-making. The economic argument for compost was the one that always wins it."

Lessons learned Joseph Fogarty is a 26-year-old primary school teacher living in Glasnevin, Dublin. He believes in being a responsible teacher, and as such, he has a taken a strong stand against commercial sponsorship in schools. This is at a time when he sees advertisers increasingly encroach upon the education system.

From the start of his career, he began to notice "the number of companies who were seeking to advertise or sell their goods through our school.

"Historically, commercial schemes have been commonplace and have been unopposed within Irish schools for years.

But now they are becoming an industry unto themselves, as in the US, Britain and Australia."

With a group of teachers, parents and "concerned individuals", Fogarty established the Campaign for Commercial Free Education in 2005, "to draw attention to the scale and the dangers of corporate exploitation of Irish schools". "We've been kept busy assessing schemes from Tesco, Supervalu, Spar, Renault, Cadbury, Le Crunch, Scholastic, McDonalds, Primary Times, Domestos, Hewlett Packard and many others."

These days commercial sponsorship is flashy, expensive, and as Fogarty points out, exploitative. "In 2002, the government cut the PE equipment grant to Irish schools and it wasn't long before McDonalds capitalised with heavily branded footballs and bibs in 92% of primary schools, turning children into walking sandwich boards."

Fogarty feels attempting to build brand loyalty at such an early age smacks of exploiting the young and under-privileged.

In 2005, Tesco launched its celebrity-endorsed Sports for Schools programme which offered 'free' equipment in exchange for vouchers for every 10 spent with the supermarket chain.

"A captain's armband (retail: 3.50) meant spending 900 at Tesco, " says Fogarty. "More recently, Supervalu dived into the market with Kids in Action. This required a total spend of 3,950 to obtain a single gaelic football (retail: 18)."

In defence of their marketing initiatives, one advertising executive says: "Parents collecting tokens to redeem free goods, be it computers or sports equipment, is hardly the effect of sinister marketing to children. These types of campaigns tend to be highly successful, because customers are rewarded for their custom; it's as simple as that."

But Fogarty claims, "These schemes require teachers and children to do the work of supermarket promoters. They pressurise parents unfairly and discriminate against smaller and disadvantaged schools who can't achieve the enormous volume of shopping required. We believe the quality of education available to your child shouldn't depend on where you shop, as that has nothing to do with teachers or school."

Fogarty doesn't shop in Tesco, eat McDonalds or parade around in Nike t-shirts. At heart, he's just a man with principles. And that's precisely what he prescribes to those seeking to live more ethically.

"I would say establish a principle, something you feel committed to, and don't be shy about defending it. In a world full of PR spin and hidden agendas, it's important to stand firm in defence of your beliefs . . . that's how things change ultimately."