“I have found one thought experiment very effective in introducing sobriety to minds drunk on human supremacy. Start with the idea that in the hierarchy of being humans rank higher than trees. When we breathe, human inhale oxygen and exhale carbon dioxide. In the presence of the sun trees do the opposite. As part of their life process of photosynthesis, they take in carbon dioxide and emit oxygen. Photosynthesis is responsible for producing a great amount of the oxygen content of the Earth’s atmosphere. Take away trees, and humans would suffocate. Take away humans, and trees would do just fine (probably better, for we wouldn’t be cutting them down). Who needs whom more? Which is more valuable? By what criterion? In view of the human need to breathe, the hierarchy of being based on matter-spirit dualism does not make sense.”