Epistemological Pluralism and the Revaluation of the Concrete By Sherry Turkle and Seymour Papert Versions of this article appeared in the Journal of Mathematical Behavior, Vol. 11, No.1, in March, 1992, pp. 3-33; Constructionism, I. Harel & S. Papert, Eds. (Ablex Publishing Corporation, 1991), pp.161-191; and SIGNS: Journal of Women in Culture and Society, Autumn 1990, Vol. 16 (1). EPISTEMOLOGICA