The Man Who Knew Coolidge, written by Sinclair Lewis, is a satirical novel that presents a humorous and critical view of American life in the 1920s. The book centers around the character Lowell Schmaltz, who claims to have personal acquaintance with President Calvin Coolidge. Schmaltz, a boastful and self-aggrandizing narrator, is a typical Lewis character used to expose the pretensions and follies of middle-class America. Lewis uses sharp wit and irony to explore themes such as the American Dream, the pursuit of success, and the emptiness of materialism. The book is also notable for its commentary on political and social issues of the era, including business ethics, corruption, and the influence of media.