Environmental problems are closely related to human activities, especially economic activities. Nevertheless, on a personal level, we do not face these problems and seem to avoid them. Why are environmental problems not taken seriously despite their urgency? As economic activities for self-profit, including money, are the essence of human behavior, we have hypothesized that, "selfishness and endless desire are the essence of human beings' instinct for survival, and as a result, environmental destruction occurs". In this paper, first, we describe through the prism of evolution how the "selfish gene" affects the survival of cells, individuals, and human society. At the same time, we detail how humans have developed the cerebrum, acquired intelligence, and developed science. Second, we describe the mechanism of modern capitalism and the global environmental situation at present. Third, we consider the relationship between human selfishness and environmental problems from three viewpoints: game theory, behavioral economics, and sociology. Finally, we propose countermeasures to environmental problems from three perspectives: social psychology, social system, and new technologies.
Keywords: economics; environment; game theory; gene; selfishness.