15 ideas
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] |
9186 | First-order logic concerns objects; second-order adds properties, kinds, relations and functions [Dummett] |
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] |
7544 | Many people imagine that to experience is to understand [Goethe] |
7541 | Man never understands how anthropomorphic he is [Goethe] |
7543 | We gain self-knowledge through action, not thought - especially when doing our duty [Goethe] |
7540 | Beauty is a manifestation of secret natural laws [Goethe] |
7538 | The happiest people link the beginning and end of life [Goethe] |
7542 | The best form of government teaches us to govern ourselves [Goethe] |
7539 | To get duties from people without rights, you must pay them well [Goethe] |
19399 | Prime matter is nothing when it is at rest [Leibniz] |