Vegetarianism is ahimsa in action, toward animals and the environment, and such ethical eating is at the heart of celebrating the Earth today and every day.

This Earth Day, I found myself reading a New York Times interview with Colin Spencer, a great food historian, artist, novelist, analyst, activist, playwright, and journalist. According to Spencer, vegetarianism is "heretical" eating—it is "not simply a criticism of meat-eating but a criticism ...