Charles Sanders Peirce was an American philosopher, logician, scientist, and founder of pragmatism whose life moved between brilliant insight and professional frustration. Born in 1839 in Cambridge, Massachusetts, and educated in an intellectually distinguished household, he spent much of his career working as a scientist and surveyor for the U.S. Coast and Geodetic Survey while pursuing a vast, original body of philosophical and scientific writing on the side. Though he never achieved the full academic recognition he deserved in his lifetime, Peirce became one of the most inventive thinkers of the nineteenth century, making major contributions to logic, semiotics, the philosophy of science, and theories of inquiry and truth. His essays explore how human beings reason under uncertainty, how signs create meaning, and how belief is shaped through experience, experiment, and community rather than by certainty alone. At the heart of his work are ideas that remain strikingly modern: the importance of testing ideas against reality, the role of chance in nature and thought, and the need for humility in the search for knowledge. Peirce's legacy is immense because he helped lay the groundwork for analytic philosophy, modern semiotics, and pragmatic approaches to science and communication, influencing thinkers across disciplines long after his death in 1914. Readers today still turn to him for a vision of intelligence that is rigorous yet open-ended, skeptical yet hopeful. He will especially appeal to readers interested in philosophy, logic, science, and anyone drawn to big ideas about how we know what we know.