sports in particular offer satisfying opportunities for class warfare, as when the middle class lobbies to outlaw the cockfighting enjoyed by the lower classes and the foxhunts enjoyed by the upper ones.262 Thomas Macaulay’s remark that “the Puritan hated bearbaiting, not because it gave pain to the bear, but because it gave pleasure to the spectators” can mean that campaigns against violence tend to target the mindset of cruelty rather than just the harm to victims. But it also captures the insight that zoophily can shade into misanthropy.
The Jewish dietary laws are an ancient example of the confused motives behind taboos on meat. Leviticus and Deuteronomy present the laws as unadorned diktats, since God is under no obligation to justify his commandments to mere mortals. But according to later rabbinical interpretations, the laws foster a concern with animal welfare, if only by forcing Jews to stop and think about the fact that the source of their meat is a living thing, ultimately belonging to God.263 Animals must be dispatched by a professional slaughterer who severs the animal’s carotid artery, trachea, and esophagus with a clean swipe of a nick-free knife. This indeed may have been the most humane technology of the time, and was certainly better than cutting parts off a living animal or roasting it alive. But it is far from a painless death, and some humane societies today have sought to ban the practice. The commandment not to “seethe a kid in its mother’s milk,” the basis for the prohibition of mixing meat with dairy products, has also been interpreted as an expression of compassion for animals. But when you think about it, it’s really an expression of the sensibilities of the observer. To a kid that is about to be turned into stewing meat, the ingredients of the sauce are the least of its concerns.
Cultures that have gone all the way to vegetarianism are also driven by a mixture of motives.264 In the 6th century BCE Pythagoras started a cult that did more than measure the sides of triangles: he and his followers avoided meat, largely because they believed in the transmigration of souls from body to body, including those of animals. Before the word vegetarian was coined in the 1840s, an abstention from meat and fish was called “the Pythagorean diet.” The Hindus too based their vegetarianism on the doctrine of reincarnation, though cynical anthropologists like Marvin Harris have offered a more prosaic explanation: cattle in India were more precious as plow animals and dispensers of milk and dung (used as fuel and fertilizer) than they would have been as the main ingredient in beef curry.265 The spiritual rationale of Hindu vegetarianism was carried over into Buddhism and Jainism, though with a more explicit concern for animals rooted in a philosophy of nonviolence. Jain monks sweep the ground in front of them so as not to tread on insects, and some wear masks to avoid killing microbes by inhaling them.
But any intuition that vegetarianism and humanitarianism go together was shattered in the 20th-century by the treatment of animals under Nazism.266 Hitler and many of his henchmen were vegetarians, not so much out of compassion for animals as from an obsession with purity, a pagan desire to reconnect to the soil, and a reaction to the anthropocentrism and meat rituals of Judaism. In an unsurpassed display of the human capacity for moral compartmentalization, the Nazis, despite their unspeakable experiments on living humans, instituted the strongest laws for the protection of animals in research that Europe had ever seen. Their laws also mandated humane treatment of animals in farms, movie sets, and restaurants, where fish had to be anesthetized and lobsters killed swiftly before they were cooked. Ever since that bizarre chapter in the history of animal rights, advocates of vegetarianism have had to retire one of their oldest arguments: that eating meat makes people aggressive, and abstaining from it makes them peaceful.
Some of the early expressions of a genuinely ethical concern for animals took place in the Renaissance. Europeans had become curious about vegetarianism when reports came back from India of entire nations that lived without meat. Several writers, including Erasmus and Montaigne, condemned the mistreatment of animals in hunting and butchery, and one of them, Leonardo da Vinci, became a vegetarian himself.
But it was in the 18th and 19th centuries that arguments for animal rights began to catch on. Part of the impetus was scientific. Descartes’ substance dualism, which considered consciousness a free-floating entity that works