The document discusses man's relationship with nature. It divides this relationship into two parts: 1) Man's interaction with the physical environment and the ecological problems this causes, and 2) Man's mastery over nature and himself, which is related to human development issues. While man enjoys nature's resources, he also inevitably destroys them in the process. This destruction is rooted in man's selfishness and lack of social consciousness. The document suggests that while man has control over the physical world, he often lacks self-control and is a slave to his own passions. True mastery involves knowing oneself.