Abstract
This chapter explores some basic tenets of pragmatist philosophy of logic to inquire into its fruitfulness to understand diverse patterns of thinking. Reference will be made to C. S. Peirce theory of reasoning as developed in his famous paper “The Fixation of Belief” and to John Dewey’s mature logic of inquiry. The different phases of Dewey’s philosophy of logic are examined in turn. It will be contended that Dewey completes the process of naturalization of thinking begun by Peirce, developing an anthropology of thought and logic that places the practice of doubting at its heart. The upshot of the paper is that doubting is at the same time a practice which demands training and the potential source of a pleasurable experience, provided an initial fear of incertitude is overcome. The paper follows the various logical stages through which the ambivalent value of doubt is dealt; the evolution that is observed at the level of humanity, of individual growth, and of western civilization.