Professor Emeritus at Harvard University, is arguably one of the most important contemporary philosophers. The richness and depth of his work not only notable for the breadth of their discussions on various philosophical topics in areas (such as the philosophy of language, philosophy of science, epistemology and philosophy of mind), but also by the remarkable transformations of its realistic over more than five decades positions. Since the second half of the eighties of the last century has been developing commensurate with its realistic moral philosophy while offering a brilliant rehabilitation of central themes of American pragmatism approaches. Among his works translated into Castilian worth noting The many faces of realism (1994), Pragmatism: an open question (1999), The collapse of the fact-value dichotomy and other essays (2004) Reason, Truth and History (2006) .