"Perhaps one of the most important things you can do for human beings is wean them off an animal-based diet. It hardens the arteries and runs up our health-care costs. The last thing a poor person can afford is a heart attack or cancer or a stroke. And that's all linked to a meat-based diet. I think animal liberation is human liberation."

Next Quote

Typically, defenders of experiments on animals do not deny that animals suffer. They cannot deny the animals' suffering, because they need to stress the similarities between humans and other animals in order to claim that their experiments may have some relevance for human purposes. The experimenter who forces rats to choose between starvation and electric shock to see if they develop ulcers (which they do) does so because the rat has a nervous system very similar to a human being's, and presumably feels an electric shock in a similar way.

— Peter Singer