"As a man thinketh" by James Allen is a self-help book published in 1903. Drawing inspiration from a biblical proverb, Allen explores the power of thought and how it shapes our lives and circumstances. He argues that each person holds the key to their conditions through their own thinking, and by working patiently on their thoughts, they can remake their life and transform their circumstances. The book aims to be simple and practical, offering methods readers can easily apply.