This book analyzes the fundamental elements of human emotional evolution from the perspective of evolutionary theory, outlining the internal logic of male-female competition. It takes you directly to the essence of love and marriage, providing profound insights into marriage. The author, with subtle humor and concise, engaging writing, vividly reveals the nuanced truths of emotional interactions between the sexes. Gender relationships are the result of long-term evolution. From courtship and mate selection to marriage and reproduction, all human romantic behaviors are underpinned by an inherent logic of competition. Over time, these gender relationships have evolved into their current forms, driven by the goal of maximizing reproductive returns with minimal investment.