20 ideas
21918 | Sufficient Reason can't be proved, because all proof presupposes it [Schopenhauer, by Lewis,PB] |
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] |
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] |
21920 | No need for a priori categories, since sufficient reason shows the interrelations [Schopenhauer, by Lewis,PB] |
16669 | Everything that exists is either a being, or some mode of a being [Malebranche] |
21362 | Necessity is physical, logical, mathematical or moral [Schopenhauer, by Janaway] |
21361 | For Schopenhauer, material things would not exist without the mind [Schopenhauer, by Janaway] |
21919 | Object for a subject and representation are the same thing [Schopenhauer] |
21917 | The four explanations: objects by causes, concepts by ground, maths by spacetime, ethics by motive [Schopenhauer, by Lewis,PB] |
21921 | Concepts are abstracted from perceptions [Schopenhauer, by Lewis,PB] |
21363 | Motivation is causality seen from within [Schopenhauer] |
12726 | In a true cause we see a necessary connection [Malebranche] |