He wants to prepare us for what he describes as a "transformative moment," when we look at the meat or animal product on our plate (fish, fowl, mammal, egg, milk, cheese) and acknowledge that it came from a living being, capable, he has no doubt, of suffering and happiness. Like children when they are first told that the drumstick is actually a leg, the tongue is really a tongue, the bacon was once a pig like Wilbur in "Charlotte's Web," Masson hopes, with all his heart, that we will say, "Eeeuwww, yuck."

It's a challenge to create transformative moments with books, but he does it. Pages lack the physical threat, the shock of the Buddhist master's stick on the back to wake up the wayward meditator. They lack the drumbeat. Words travel, so often, through the head on their long journey to the heart. Masson is a wise, clear writer, but it doesn't hurt, while reading this important book, to look at the image of the young cow on the cover or the 67-year-old author's vivid, healthy photo on the back flap.

Here's how Masson builds his argument: First, we've been fed a myth of man as hunter; structurally, we lack the teeth, the jaw and the digesting enzymes of carnivores. A false sense of our uniqueness as humans, as opposed to true understanding of our animal nature and the fact that we share more than 95% of our DNA with some animals (depending, of course, on the animal), has allowed us to deny their suffering or to rationalize killing them for food as their subservient role on the planet.

Second, supporting agribusiness, which is responsible for three-fourths of the nitrous oxide emissions and two-thirds of the methane in our atmosphere, and particularly supporting killing animals, contributes more to global warming and toxicity in our environment than any other human activity. Third, and most people know this by now, meat is not good for us. We can get our protein elsewhere and our B vitamins from supplements.

Finally, the happiness of animals matters. Denying our instinct -- the voice that tells us this when we eat animals, when we hear about how they are raised and mistreated -- is unhealthy for us. Masson does not hold back here; he is hard even on fellow local, organic food proponents like Barbara Kingsolver, whose book "Animal, Vegetable, Miracle: A Year of Food Life" included sections on animal slaughter that Masson found offensively cavalier. He depends, in his own life, on the Buddhist concept of ahimsa, or nonviolence, and in the effort to live without causing harm.

Masson began his public life as a Sanskrit scholar. After finding and reading some of Freud's letters on child sexual abuse, he studied and wrote extensively about Freudian psychoanalysis. In the last two decades, he has written several books on the emotional lives of animals: elephants, farm animals, cats and dogs. He grew up in Los Angeles, the son of two vegetarians, and moved in and out of vegetarianism. He has been vegan for many years now and includes his own experience (including what he eats on an average day) here.

"The Face on Your Plate" is one of many by scholars, scientists, fiction writers, animal-rights activists, environmentalists and journalists (Kingsolver, Michael Pollan, Peter Singer, Theo Colborn, Alice Waters, Jane Goodall, Marion Nestle, Carl Honoré and Eric Schlosser, to name a few) written in the last few years that implore readers to consider and reimagine how what they eat affects not just their own health but the health of the Earth. Each has a different slant -- eat local, buy organic, etc. Masson's aim is a life with a purpose; his interests follow a powerful trajectory that has led him here, bringing everything to bear on the certainty that eating meat is cruel and immoral.