On May 14, 1867, the 27-year-old
Charles Sanders Peirce, who eventually founded
Pragmatism, presented a paper entitled "" to the
American Academy of Arts and Sciences. Among other things, this paper outlined a theory of predication involving three universal
categories that Peirce continued to apply in philosophy and elsewhere for the rest of his life. In the categories one will discern, concentrated, the pattern which one finds formed by the three grades of clearness in "" (1878 foundational paper for pragmatism), and in numerous other three-way distinctions in his work.