Buddhism vegetarian, also based on the principle of equality. The Buddhist thought, all beings have Buddha nature, the future can become a buddha. In other words, now all beings is the future buddha. Buddha said: "every man is my father, my mother and all women." Push and, to all sentient beings, the male is the father, the female is the mother. So, today killed by eating animals, is in the past, the future Buddha parents. The Buddha said "parents" is a convenient argument, the Buddhists have precaution heart, so as to avoid the carnivorous.
Of course, to analyze the theory from the view of modern science, there is no reason. We said "parents", is entirely from the blood relationship, social distinction. But from look on the relationship between the species, with people and other animal, to create harmony, respect each other's survival chain, this notion is meaningful. From the species coexistence perspective, human and other species are equally valuable. Net due to master in "kill cruel" in say: "man is an animal, or omnivorous animal. Nobody said this would be to eat meat. We can eat vegetables, fruits and nuts. We think very noble, but never equal heart, never and we have the same life animal thought. We all look down their feelings, deny their existence significance, that the other animal existence, in order that we taste. We don't keep the animal and people as equal...... Our moral in where? We all know we can't kill, can we can kill other non-human animal? They like us, is the right to life." Some of these species equal natural humanitarianism view and modern animal protector of the concept is the same. The scholar said "no mercy, the body great mercy" concept, and some propositions of modern ecological ethics is the same.