The great virtue of a diversified food economy, like a diverse pasture or farm, is its ability to withstand any shock. The important thing is that there be multiple food chains, so that when any one of them fails-when the oil runs out, when mad cow or other food-borne diseases become epidemic, when the pesticides no longer work, when drought strikes and plagues come and soils blow away-we'll still have a way to feed ourselves.

There's a lot of research that suggests that organic yields are close or superior to conventional yields depending on factors like climate. In a drought year an organic field of corn will yield more - considerably more - than a conventional field; organic fields hold moisture better so they don't need as much water. It simply isn't true that organic yields are lower than conventional yields.

The correlation between poverty and obesity can be traced to agricultural policies and subsidies.

To ferment your own food is to lodge a small but eloquent protest - on behalf of the senses and the microbes - against the homogenization of flavors and food experiences now rolling like a great, undifferentiated lawn across the globe.

There are fundamental tensions between the biological reality of the planet and the economic reality. To some extent you can adapt the economy, create a new set of rules and incentives to send it down a better track, but finally people in the first world are going to have to consume a whole lot less.

One surprise is how deeply the food system is implicated in climate change. I don't think that has really been on people's radar until very recently. 25 to 33 percent of climate change gases can be traced to the food system. I was also surprised that those diseases that we take for granted as what will kill us - heart disease, cancer, diabetes - were virtually unknown 150 years ago, before we began eating this way.

I really do think that cooking is very important. It's really important for the farmers because it means you're going to be buying real food and not processed food, so that means the farmers will capture more of your food dollar.