I am a professor of philosophy at the University of Oslo and at Universidade Federal do Rio Grande do Norte in Brazil.
9 A question on an ordinal for ZFC- jul 31 '13
6 How short can we state the Axiom of Choice? aug 17 '14
4 A question on the minimal ordinal for ZFC aug 3 '13
4 Collection from Replacement in ZFC-extensionality dec 20 '12
4 On a modal correspondence mar 31 '14