In Next Screen I speculated:

I wonder if we might not be nearing another inflection point where there is a general awakening and resultant collapse of totalitarian forces. . . We can already see that the Kyoto block has failed to cut emissions . . . I think that we have the information needed to refute the Kyoto bloc but it may still be some time before that information penetrates public consciousness.

Perhaps these crumbs mark a trail of sorts.

Values, the refuge of scoundrels.

the debate over next steps is as much about values as data. The consequences of various decisions over greenhouse gases are framed by science. But choices made by countries, communities and individuals are being shaped by a mix of history, geographic circumstance, money and – especially – values. . .

It’s not just banner-waving environmentalists and banjo-plucking folkies who see values as a key to the climate question. Last week, Jerry Taylor, who writes on economics and the environment for the libertarian Cato Institute, chided a group of climate scientists for issuing a call in Bali for sharp cuts in greenhouse gases, saying their expertise in climate science gave them no special standing to dictate how society should respond to warming.

How do you choose between alternative and equally ineffective pseudo-green fashion statements?

The local food, or locavore, movement has so much momentum that some of the food glitterati have declared that such food is better than organic.

But now comes a team of researchers from the University of California, Davis, who have started asking provocative questions about the carbon footprint of food. Those questions threaten to undermine some of the feel-good locavore story line . . .

If a low-carbon diet is your goal, Mr. Tomich suggests, it may be more effective to change your diet than to focus on eating local. After all, a plant-based diet tends to have a much smaller carbon footprint than a diet that includes meat. That is because a pound of steak requires many more pounds of grain as feed — and all the carbon emissions associated with that, from fertilizers that are derived from fossil fuels to the fuel for the combines used for the harvest, he said.

And if you insist on eating meat, as I do, then perhaps it’s better for the environment to eat poultry rather than red meat and grass-fed rather than grain-fed. Mr. Tomich’s team is trying to sort that out. . .

At some point, the ethical maze can make you dizzy. But there was one line of inquiry from the California researchers that hit particularly close to home: the carbon impact of shoppers themselves. . .

Certainly, there are many reasons for eating local food — from supporting local farmers to a desire for fresher, potentially tastier food. The research in California, however, offers the prospect of a more nuanced debate on eating a low-carbon diet. In the meantime, Ms. Feenstra said, the research has already led her to one conclusion:

Don’t drive your sport utility vehicle to the farmers’ market, buy one food item and drive home again. Even if you are using reusable bags.

Briefly, values are a tertiary consideration. First, one must bravely face reality without value filters. Then, one must admit abysmal ignorance, an embarrassingly meager ability to grasp reality. In the remote chance that one has mastered the primary and secondary considerations then values can be a tie breaker between near equal choices.

For example: local or organic? In truth, neither are effective ways to respond to climate change, and neither are particularly relevant to any other real world measure. So, values are all that matter. It's a fashion statement, a life-style choice, a way to signal status or at least aspiration to a particular status (it isn't clear if this is truly high status), or maybe just a way to meet babes. Whatever.

But, be careful of misinformation. The claim that "a plant-based diet tends to have a much smaller carbon footprint than a diet that includes meat" is false. It depends on which plants, which meats, and how they were produced. Moreover, there are other issues an aspiring fashion victim should consider such as the impact on biodiversity, water etc. There are also socio-economic considerations. Environmental concern isn't the only value a poser needs to fake.

My advice to aspiring rationalists is to go for the gusto. If it tastes good eat it. The difference between fashionable food and common food in environmental terms is so small, plus or minus either way, that it is irrelevant. Health considerations are more important. If it tastes good and is good for you - be careful of quacks here too - then enjoy it with a clear conscience and a contented smile.