The history of philosophy is not like the history of the sciences to be studied with the intellect alone. That which is receptive in us and that which impinges upon us from history is the reality of man's being unfolding itself in thought.
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.