In three comprehensive volumes, Logic of the Future presents a fullpanorama of Charles S. Peirce s important late writings. Among themost influential American thinkers, Peirce took his existential graphs tobe his greatest contribution to human thought. The manuscriptsfrom 1895-1913, most of which are published here for the first time, testify therichness and open-endedness of his theory of logic and its applications. They also invite us to reconsider our ordinary conceptions of reasoning aswell as the conventional stories told about the evolution of modern logic. Peirce s 1904-1908 writings on pragmaticism define his mature philosophy, grounded upon the principles of logical analysis as provided by existential graphs. This third volume of the series includes a comprehensive selection of letters exchanged from 1898-1913 between Peirce and his colleagues and collaborators on the logic and philosophy of existential graphs.