Francisco Rodríguez-Consuegra
Valencia University
ABSTRACT. Tarski did research on set theory and also used
set theory in many of his emblematic writings. Yet his notion of set from
the philosophical viewpoint was almost unknown. By studying mostly the
posthumously published evidence, his still unpublished materials, and the
testimonies of some of his collaborators, I try to offer here a first,
global picture of that intuitive notion, together with a philosophical
interpretation of it. This is made by using several notions of universal
languages as framework, and by taking into consideration the evolution
of Tarski's thoughts about set theory and its relationship with logic and
mathematics. As a result, his difficulties to reconcile nominalism and
methodological Platonism are precisely located, described and much better
understood.