Robert Collier

Robert Collier (1885–1950) was an American author associated with self-help and advertising. He is best known for *The Secret of the Ages*, a work that presents ideas about personal success and the power of thought, and for *The Robert Collier Letter Book*, a widely read guide to writing sales letters and advertising copy. Collier’s writing helped popularize early twentieth-century motivational themes and practical persuasion techniques for business. His books have remained in print and are frequently cited in discussions of copywriting and positive-thinking literature. He died in 1950, leaving a legacy tied to both inspirational writing and direct-response advertising.