Humans live and can only live in the real world. What is the “real world” for human beings? The moment when human beings emerged, they encountered the natural world. Nature precedes human beings. Humans are products of natural evolution. Humans cannot escape nature after their emergence because they need the natural world to survive. However, the existing world is not equal to the real world for human beings. Only that world, which is fit for human nature and human life, is the real world for human beings. The original natural world is only a precondition for the survival of human beings; it does not directly satisfy the needs of the survival and life of humans. This natural world can be considered the real world for animals but not for humans. Animals emerge from nature, live in nature and are governed by nature; nature is their natural paradise.