William James' Pragmatism is a seminal work in American philosophy that explores the practical implications of ideas and beliefs. James argues that the truth of an idea lies in its practical consequences. In other words, an idea is true if it works and is useful. This pragmatic approach emphasizes the importance of experience and experimentation in determining the validity of knowledge.

The book delves into various philosophical concepts, including truth, meaning, and morality, through a pragmatic lens. James challenges traditional philosophical methods that prioritize abstract reasoning and instead advocates for a more concrete and action-oriented approach to understanding the world.