Human economic and social activity is contingent on environmental stability. If humans are to live on the earth, the following basic principles must be adhered to: (1) Isolate human beings from nature (protect the natural environment), i.e. maximize the volume of nature and minimize contact with it be human beings, the cause of pollution, and (2) reuse items contaminated by human beings (recycling-based society), i.e. if humans, the source of contamination, cause contamination for unavoidable reasons, minimize the destruction of the natural world through reuse and recycling.