My friend Andrea, cooking supper for a group of us at his home, mentioned that a mutual friend hadn't been able to join us because he was at the 'fish extinction awards, otherwise known as the sushi awards'. And so we got talking about the perilous state of bluefin tuna stocks (this magnificent fish is almost certain to be extinct within three years - just watch The End of the Line to see why).

And what I really wondered was why the Japanese, who have so much to lose, are so utterly cavalier in their approach to over-fishing. After all, there is very little meat in traditional Japanese cooking - their entire culinary culture, their identity, their way of life, their health, is bound up with fish. Japanese cuisine without raw fish, without bonito (that magic ingredient in dashi) is almost unimaginable. And with the loss of bluefin tuna such an immediate prospect, and the loss of so many other types of fish also looming in the not-distant future, why isn't there more public concern, and action? It's insane.

But then I reflected that it's not much different from the staggering blindness of most of the human race - after, most of us are blithely trying to carry on as normal while we wipe out other species at a terrifying rate, pollute our surroundings, avoid thinking about the End of Oil, and chit-chat about climate change as if destabilising the ecological systems which sustain us was just another little political issue... Viewed with detachment, it's as inexplicable as the behaviour of the Easter Islanders, who chopped down all their trees upon which their civilisation depended, and disappeared from the face of the earth. (Of course I'm thinking here of Jared Diamond's brilliant Collapse, an account of how and why societies self-destruct.)