Here’s my cat – Keith. He looks cute, doesn’t he? But actually, he’s a killer. I’ve seen him torture things for his amusement – he wasn’t hungry and he didn’t want them to die quickly (less fun). I know without a shadow of a doubt that he’d torture and kill me if I were smaller than him and I couldn’t constantly provide him with food. Maybe he’d do it anyway.

He’s made me realise that nature is merciless. And she will show us no mercy if we refuse to respect her. Only the fittest species survive, and fitness includes the ability to see that you have to live in balance with nature. Bacteria in a petri dish can’t see it, but we should – we’re better than that.

Humans need an ‘economy’ – even a peasant economy. We need to do things – to eat, to stay warm, to stay healthy and to have a good time. I think most of us would like some sort of a surplus too – to try to increase our ability to find out more about existence. To seek enlightenment.

But we’re doing too much. It’s damaging nature.

Nature has been badly damaged before, by volcanic activity and asteroid impacts. But this time it’s human activity – toxifying, appropriating habitats and removing biomass, which causes runaway extinctions. Extinctions are growing exponentially. Anyone with a basic grasp of maths will know that means trouble.

We fight with nature at out peril. She’s much stronger than us and she shows no mercy.