In the year 2070, a 50-year-old individual reflects on a drastically changed world suffering from severe water scarcity and environmental degradation. The letter outlines the adverse effects of water shortages on health, society, and the economy, highlighting issues such as dehydration, synthetic food, and the high cost of breathable air. The author expresses deep regret for previous generations' neglect of environmental warnings, believing that life on Earth may soon become impossible due to irreversible damage.