Mencius’ famous saying, “If one enters the country, he will be helpless, and if he goes out he will be invincible, and the country will perish.” This reveals the key factors for the survival of a country. It emphasizes that if a country lacks firm internal enforcers of laws and talented people who can assist the monarch, and at the same time does not have sufficient rivals and external threats abroad, such a country will often find it difficult to achieve lasting stability. Through the article "Born in Sorrow, Die in Ease", Mencius used rigorous arguments and vivid historical examples to explain how difficulties and challenges can promote the growth of countries and individuals, while a comfortable life may lead to the decline of a country. Only when people face difficulties and challenges can they correct their mistakes and stimulate their potential. The same is true for countries. Only when driven by internal and external pressure can they maintain progress and strength. Therefore, this famous saying profoundly explains the importance of hardship to the survival of the country, reminding us that neither individuals nor countries can ignore the value of growth and challenges in difficult times.