13 ideas
10528 | Definitions concern how we should speak, not how things are [Fine,K] |
21566 | 'Propositional functions' are ambiguous until the variable is given a value [Russell] |
21567 | 'All judgements made by Epimenedes are true' needs the judgements to be of the same type [Russell] |
10529 | If Hume's Principle can define numbers, we needn't worry about its truth [Fine,K] |
10530 | Hume's Principle is either adequate for number but fails to define properly, or vice versa [Fine,K] |
23457 | Type theory cannot identify features across levels (because such predicates break the rules) [Morris,M on Russell] |
21556 | Classes are defined by propositional functions, and functions are typed, with an axiom of reducibility [Russell, by Lackey] |
21568 | A one-variable function is only 'predicative' if it is one order above its arguments [Russell] |
10527 | An abstraction principle should not 'inflate', producing more abstractions than objects [Fine,K] |
17402 | Mendeleev saw three principles in nature: matter, force and spirit (where the latter seems to be essence) [Mendeleev, by Scerri] |
17399 | Elements don't survive in compounds, but the 'substance' of the element does [Mendeleev] |
17400 | Mendeleev focused on abstract elements, not simple substances, so he got to their essence [Mendeleev, by Scerri] |
17401 | Mendeleev had a view of elements which allowed him to overlook some conflicting observations [Mendeleev] |