A transcendental view on the continuum: Woodin’s conditional platonism Jean PETITOT∗ December 2007 To appear in Intellectica. Abstract One of the main difficulty concerning the nature of the continuum is to do justice, inside the set theoretical Cantorian framework, to the classical conception (from Aristotle to Thom, via Kant, Peirce, Brentano, Husserl and Weyl) according to which the continuum is a non-compositional, cohesive, primitive, and intuitive datum. This pa- per investigates such possibilities, from G¨odel to Woodin, of modelling inside a ZFC -universe the transcendence of the intuitive continuum w.r.t. its symbolic determination. Keywords: constructive universe, continuum, G¨odel, forcing, Kant, large cardinals, Ω-logic, projective hierarchy, V = L, Woodin, 0#. 1 Introduction One of the main general philosophical problem raised by the nature of the continuum is the conflict between two traditions: the older one, which can be called “neo-Aristotelian”, even if this sounds rather vague, and the now the classical one, namely the Cantorian tradition. arXiv:1502.05898v1 [math.LO] 20 Feb 2015 According to the neo-Aristotelian tradition, the continuum is experi- enced and thought of as a non-compositional, cohesive, primitive, and ∗EHESS & CREA (Ecole Polytechnique), France.
[email protected]. 1 intuitive datum. It can be segmented into parts but these parts are themselves continua and points are only their boundaries. This point of view was very well defended by Kant. As soon as in his 1770 Dissertatio, he emphasized the fact that “a magnitude is continuous when it is not composed out of simple elements” (AK, II, p. 399 1), and explained that for the continuous “pure intuitions” of space and time “any part of time is still a time, and the simple elements which are in time, namely the moments, are not parts but limits between which a time takes place” (AK, II, p.