Long And Difficult Art

Few persons care to study logic, because everybody conceives himself to be proficient enough in the art of reasoning already.  But I observe that this satisfaction is limited to one's own ratiocination and does not extend to that of other men.

We come to the full possession of our power of drawing inferences the last of all our faculties, for it is not so much a natural gift as a long and difficult art.

-- Charles Sanders Peirce [pronounced like purse] (10 September 1839 - 19 April 1914), American philosopher, chemist, and polymath, now remembered as a pioneer of the field of semiotics and, with the formulation of the pragmatic maxim, the founder of the philosophies of Pragmatism and Pragmaticism, "Illustrations of the Logic of Science" First Paper -- The Fixation of Belief", in Popular Science Monthly, Vol. 12 (November 1877)