Book excerpt: In three comprehensive volumes divided into five books, Logic of the Future presents a full panorama of Charles S. Peirce's important late writings. Among the most influential American thinkers, Peirce took his existential graphs to be his greatest contribution to human thought. The manuscripts and letters from 1895–1913, most of which are published here for the first time, testify the richness and open-endedness of his theory of logic and its applications. They also invite us to reconsider our ordinary conceptions of reasoning as well as the conventional stories told about the evolution of modern logic. This first part of the third volume (Volume 3/1) of the Logic of the Future series contains Peirce's 1904–1909 writings on his mature philosophy of pragmaticism, which is grounded upon the principles of logical analysis as provided by existential graphs.