6 ideas
13831 | Logic is based on transitions between sentences [Prawitz] |
13825 | Natural deduction introduction rules may represent 'definitions' of logical connectives [Prawitz] |
13823 | In natural deduction, inferences are atomic steps involving just one logical constant [Prawitz] |
14895 | 'Superficial' contingency: false in some world; 'Deep' contingency: no obvious verification [Evans, by Macià/Garcia-Carpentiro] |
11881 | Rigid designators can be meaningful even if empty [Evans, by Mackie,P] |
21097 | Modern monarchies are (like republics) rule by law, rather than by men [Hume] |