The 73-year-old designer and campaigner on what drives her, the last time she cried and why she eats so much lettuce
I was anti-religious at one time. I'm not any more. The concept of God and the divine is very important. Human beings have the potential to evolve and become more and more wonderful because they are aiming at that perfection.
I do things that irritate people. I'm always saving things, telling people to turn taps off. My husband, Andreas, used to get fed up with me, but he's got a lot better. Some people turn on the tap before they've even put their toothpaste on [the toothbrush]. I only have a mouthful of water at the end.
I have not cried since I lived with Malcolm [McLaren, her ex-partner]. Malcolm needed me to cry every day. He just couldn't leave the house without trying to make me upset. So I stopped. I envy people who can cry.
I was born at a good time to try to understand the world. I'm aware of things that someone 100 years ago wouldn't be, such as the fact that the human race faces mass extinction pretty soon if we don't do anything. During the war, things were precious – growing up, we weren't consuming all the time. And fortunately for me the education system hadn't collapsed.
My favourite food is lettuce. Andreas and I eat one a day between us on average. I make a very good, simple salad dressing. Garlic, oil, lemon, a bit of sugar and a bit of bouillon powder – it's always different. We just love it.
Character is there from birth. The way my sons looked at me when they were first born is the same way they look at me today. My children are honourable people. They really would never shit on anybody.
The world's forgotten more than it knows. Consumption is about throwing away the past. But to engage with the world we must engage with the past through art and reading. It gives you a critique of your own life, and you realise: "I'm not doing anything. Human beings are capable of amazing things and I'm just sucking things up."
I will never vote Labour again. Not unless they get a true green economy programme in place. I said I would vote Conservative after Blair took us into Iraq. Recently I've been voting for the Green Party: they're the only ones saying something different. Ukip is the same as the others – except they don't like elephants, apparently.
Stella McCartney and I want to campaign together more. She just signed our letter demanding the government doesn't go ahead with fracking until people are made aware of the facts.
I have to like it – that's the only criteria I have when I design.
My campaigning hero is Julian Assange. He's done more to affect public opinion than anyone else. Most people don't think change is up to them; they think somehow it will just happen.
I've avoided my biography for a long time. But Andreas convinced me to do it. It's important for some people to tell you about their past, but I don't live in mine or really go over it much.
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