Every peasant cuisine has incredible ingenious tricks for getting a lot of nutrition out of a small amount of ingredients. There are people who don't have the money to invest in better food, but perhaps they have the time. There's a trade-off: The more time you're willing to put into food preparation, the less money you have to spend.

There are many people who don't do well on a vegetarian or vegan diet, that for them, meat is a very nutritious food. So, I'm not prepared to give up meat. I don't think we need to give up meat, but we certainly need to change the way we raise meat and diminish the amount of it in our diet.

The history of modern nutritionism has been a history of macronutrients at war: protein against carbs; carbs against proteins, and then fats; fats against carbs.

Wrangham cites several studies indicating that in fact humans don't do well on raw food: they can't maintain their body weight, and half of the women on a raw-food regimen stop menstruating. Devotees of raw food rely heavily on juicers and blenders, because otherwise they would have to spend as much time chewing as the chimps do. It is difficult, if not impossible, to extract sufficient energy from unprocessed plant matter to power a body with such a big, hungry brain.

You want to say the thing that will drive everybody in the direction you want to go. But as a writer you have a pact with your readers that you'll be really straight with them at all times.

That eating should be foremost about bodily health is a relatively new and, I think, destructive idea-destructive not just the pleasure of eating, which would be bad enough, but paradoxically of our health as well. Indeed, no people on earth worry more about the health consequences of their food choices than we Americans-and no people suffer from as many diet-related problems. We are becoming a nation of orthorexics: people with an unhealthy obsession with healthy eating.

The single greatest lesson the garden teaches is that our relationship to the planet need not be zero-sum, and that as long as the sun still shines and people still can plan and plant, think and do, we can, if we bother to try, find ways to provide for ourselves without diminishing the world.