Paul Laffitte (1864–1949) was a multifaceted figure—financier, journalist, publisher, and cultural entrepreneur—active in early twentieth-century Paris. Known for his investments in cinema, theater, and publishing, he also wrote satirical reflections on finance, in his best-known work, Jéroboam ou la finance sans méningite (1920), later expanded in Les Nouveaux propos de Jéroboam (1939). The book blends humor and sharp observation, offering aphorisms like “A poor idiot is an idiot, but a rich idiot is a rich man.” Through concise, ironic commentary, Laffitte exposes the vanity, herd behavior, and irrationality of financiers. He mocks financial fashions, speculative booms, and misplaced faith in statistics. He shows how numbers can seduce and mislead, and how business decisions often rely more on intuition, belief, and chance than on logic. Laffitte’s style recalls moralists and satirists, mixing wit with insight. His portrayal of “affairs” emphasizes their metaphysical, almost poetic nature rather than purely economic logic. The book was well-received for its humor and truth, praised by critics for combining entertainment with moral reflection. Though largely forgotten today, Laffitte’s work remains a unique, insider’s critique of early twentieth-century finance.