When I was 12 years old, my school arranged for our local MPs to each visit our class.

I remember David Carter coming and speaking to us. I remember Ruth Dyson doing the same thing. And last but not least, Rod Donald came and spoke to Room 22 at St Martins School. 

I can’t tell you what any of them said. I don’t know if I could have distinguished at that time what each of them stood for, but I remember looking out the window at the end of the class and seeing Rod Donald push off down the street on his bike, and thinking wow! A bike? That man must really care about conservation.

A couple of years later, I was doing my paper round, and I bumped into Jeanette Fitzsimons. I recognised her from the news. I knew she was a Green MP. But she was lost and she asked me how to get to the closest bus stop. Wow! I thought. The bus? She must really care about conservation.

In the US, they reckon politicians become Senators for one of two reasons. Number one: principle. They genuinely want to affect change. They want to better the lives of their constituents. Number Two, the second reason: Power. They want to be President.

That might be a little crude and I’m sure there’s some grey between that black and white, but I’ve always admired politicians who are clearly in politics for the right reasons. People who are drawn to politics on the strength of their convictions. They don’t realistically expect to be President or Prime Minister. They’re not drawn to the baubles of office. The fancy-schmancy dinners, the office full of staff, the chauffeur-driven ministerial limosines. None of that. They’re in it because they genuinely believe in the cause.

Now I should point out, no political party or philosophy has a monopoly on conviction. People on the left, the right, and the centre - if those definitions exist anymore - have all dedicated themselves to political work and service on the basis of authetically-held conviction.

And you would have to say, regardless of your opinion on the Green Party, that all of all us, at least to some extent, consider conservation and environmentalism a worthy and important cause. Sure we might disagree on specific policies and just how far we should go, but I would hope no reasonable person wants to destroy the Earth.

And so, when I think of Jeanette Fitzsimons, that’s it. I think of someone who clearly was in politics for the right reasons. Someone who didn’t seek fame or power but genuinely thought they could make the world a better place. Whether or not you agreed with her or not, she lived what she preached. In an individualistic age, she believed in the greater good. And in politics, a world that exposes hypocrites, there’s a lot to be said for integrity.

• Green Party's former co-leader Jeanette Fitzsimons dies