16 ideas
| 11178 | The essence or definition of an essence involves either a class of properties or a class of propositions [Fine,K] |
| 9193 | ZF set theory has variables which range over sets, 'equals' and 'member', and extensionality [Dummett] |
| 9194 | The main alternative to ZF is one which includes looser classes as well as sets [Dummett] |
| 9195 | Intuitionists reject excluded middle, not for a third value, but for possibility of proof [Dummett] |
| 11175 | Logical concepts rest on certain inferences, not on facts about implications [Fine,K] |
| 11176 | The property of Property Abstraction says any suitable condition must imply a property [Fine,K] |
| 9186 | First-order logic concerns objects; second-order adds properties, kinds, relations and functions [Dummett] |
| 11174 | A logical truth is true in virtue of the nature of the logical concepts [Fine,K] |
| 9187 | Logical truths and inference are characterized either syntactically or semantically [Dummett] |
| 9191 | Ordinals seem more basic than cardinals, since we count objects in sequence [Dummett] |
| 9192 | The number 4 has different positions in the naturals and the wholes, with the same structure [Dummett] |
| 11177 | Can the essence of an object circularly involve itself, or involve another object? [Fine,K] |
| 11173 | Being a man is a consequence of his essence, not constitutive of it [Fine,K] |
| 11179 | If there are alternative definitions, then we have three possibilities for essence [Fine,K] |
| 13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
| 20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |