us can decide how much we value, say,juicy burgersand double-dark chocolate ice cream compared to how much we value a trim waistline and longer life expectancy. And each of us values these benefits differently. The dietary choices that I make for myself are right for me, but I cannot know if they are right for anyone else. Progressives, in contrast, falsely assume there's a single correct metric, for the whole country, that determines for everyone how to trade off the satisfaction of eatingtasty but fatty foodsfor the benefit of being healthier. Here is the letter that David MacKay sent me following my article in The Times and to which I replied. (I have gone to weblinks for his charts and in one case come up with a slightly different version -- the sea ice graph I could not find the exact one he included so I have found another from the same source which has more years on it than his version, but it's the same data and the same source.) Update: all graphs now correct! Some greens have seen the light on nuclear power and GM food. It's a start. Update: I'd like to add one thing to the story below. Stewart Brand, who I know and admire, played a prominent part in the Channel 4 film. He's not a `convert' to these views. He has always been strongly pro-GM food and mildly pro-nuclear. So my comments here were not aimed at him. Last night saw a TV programme