The text presented here was written by Harold Garfinkel for the Fourth World Congress of Sociology in Stresa (Italy) in 1959, where Garfinkel participated in the Section on the Sociology of Knowledge organized by Kurt Wolff. The "General Theme" of the Fourth World Congress of Sociology was "Society and Sociological Knowledge / La Société et la Connaissance Sociologique". Garfinkel's original Stresa paper had to be "heavily abridged" for publication (Garfinkel 1961).