Little wonder that it can seem unthinkable to say "no, thanks" to the modern-day equivalent of our tribe - our fear-driven culture.

Fear doesn't necessarily mean that we have to stop. It doesn't mean that we are failures. It doesn't mean that we are cowards.

We can choose who we bring into our lives. We can choose who will reinforce our risk taking.

I think of Wangari Mathai in Kenya. If she started out saying she wanted to plant 20 million trees, she would have been laughed at. In fact, the foresters and the government did laugh at her. They said, "Villagers? Un-schooled villagers? Planting trees? No, no, no, it takes foresters." So she planted trees anyway.

We are very much social creatures who model ourselves on one another.

Making conscious choices about what we eat, based on what the earth can sustain and what our bodies need, can help remind us that our whole society must begin to balance sustainable production with human need.

I understand, of course, that grain-fed meat is not the cause of the world hunger problem - and eating some of it doesn't directly take food out of the mouths of starving people - but it is, to me, a symbol and a symptom of the basic irrationality of a food system that's divorced from human needs. Therefore, using less meat can be an important way to take responsibility. Making conscious choices about what we eat, based on what the earth can sustain and what our bodies need, can help remind us that our whole society must begin to balance sustainable production with human need.