25 ideas
10751 | Second-order logic needs the sets, and its consequence has epistemological problems [Rossberg] |
10757 | Henkin semantics has a second domain of predicates and relations (in upper case) [Rossberg] |
10759 | There are at least seven possible systems of semantics for second-order logic [Rossberg] |
10753 | Logical consequence is intuitively semantic, and captured by model theory [Rossberg] |
10752 | Γ |- S says S can be deduced from Γ; Γ |= S says a good model for Γ makes S true [Rossberg] |
10754 | In proof-theory, logical form is shown by the logical constants [Rossberg] |
13134 | We negate predicates but do not negate names [Westerhoff] |
10756 | A model is a domain, and an interpretation assigning objects, predicates, relations etc. [Rossberg] |
10758 | If models of a mathematical theory are all isomorphic, it is 'categorical', with essentially one model [Rossberg] |
10761 | Completeness can always be achieved by cunning model-design [Rossberg] |
10755 | A deductive system is only incomplete with respect to a formal semantics [Rossberg] |
13124 | Categories can be ordered by both containment and generality [Westerhoff] |
13117 | How far down before we are too specialised to have a category? [Westerhoff] |
13116 | Maybe objects in the same category have the same criteria of identity [Westerhoff] |
13118 | Categories are base-sets which are used to construct states of affairs [Westerhoff] |
13125 | Categories are held to explain why some substitutions give falsehood, and others meaninglessness [Westerhoff] |
13126 | Categories systematize our intuitions about generality, substitutability, and identity [Westerhoff] |
13130 | Categories as generalities don't give a criterion for a low-level cut-off point [Westerhoff] |
13131 | The aim is that everything should belong in some ontological category or other [Westerhoff] |
13123 | All systems have properties and relations, and most have individuals, abstracta, sets and events [Westerhoff] |
13115 | Ontological categories are like formal axioms, not unique and with necessary membership [Westerhoff] |
13119 | Categories merely systematise, and are not intrinsic to objects [Westerhoff] |
13135 | A thing's ontological category depends on what else exists, so it is contingent [Westerhoff] |
13129 | Essential kinds may be too specific to provide ontological categories [Westerhoff] |
20653 | Six reduction levels: groups, lives, cells, molecules, atoms, particles [Putnam/Oppenheim, by Watson] |