It was not until after the Chinese defeat in the First Sino-Japanese War (1894–95, fought for control of Korea) that Yan Fu became famous. He is celebrated for his translations, including Thomas Huxley's "Evolution and Ethics", Adam Smith's "The Wealth of Nations", John Stuart Mill's "On Liberty" and Herbert Spencer's "Study of Sociology". Yan critiqued the ideas of Darwin and others, offering his own interpretations. The ideas of "natural selection" and "survival of the fittest" were introduced to Chinese readers through Huxley's work. The former idea was famously rendered by Yan Fu into Chinese as "tiānzé" ().