Wittgenstein on Incompleteness Makes Paraconsistent Sense

Francesco Berto (1)

1 IHPST - Institut d'Histoire et de Philosophie des Sciences et des Techniques

I provide an interpretation of Wittgenstein's much criticized remarks on Gödel's First Incompleteness Theorem in the light of paraconsistent arithmetics: in taking Gödel's proof as a paradoxical derivation, Wittgenstein was right, given his deliberate rejection of the standard distinction between theory and metatheory. The reasoning behind the proof of the truth of the Gödel sentence is then performed within the formal system itself, which turns out to be inconsistent. I show that the models of paraconsistent arithmetics (obtained via the Meyer-Mortensen collapsing filter on the standard model) match with many intuitions underlying Wittgensteins philosophy of mathematics, such as its strict finitism and the insistence on the decidability of any meaningful mathematical question.

Mots clés: philosophy of science

Domaines: Histoire, Philosophie et Sociologie des sciences

Francesco Berto. Wittgenstein on Incompleteness Makes Paraconsistent Sense. Fourth World Congress of Paraconsistency, Jul 2008, Melbourne, Australia. pp.257-276, ⟨10.1007/978-94-007-4438-7⟩. ⟨halshs-00791677⟩