21 ideas
10757 | Henkin semantics has a second domain of predicates and relations (in upper case) [Rossberg] |
10751 | Second-order logic needs the sets, and its consequence has epistemological problems [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] |
7720 | Two things can only resemble one another in some respect, and that may reintroduce a universal [Lowe] |
7712 | On substances, Leibniz emphasises unity, Spinoza independence, Locke relations to qualities [Lowe] |
5040 | Necessary truths can be analysed into original truths; contingent truths are infinitely analysable [Leibniz] |
13159 | Only God sees contingent truths a priori [Leibniz] |
5039 | If non-existents are possible, their existence would replace what now exists, which cannot therefore be necessary [Leibniz] |
7710 | Perception is a mode of belief-acquisition, and does not involve sensation [Lowe] |
7711 | Science requires a causal theory - perception of an object must be an experience caused by the object [Lowe] |
7714 | Personal identity is a problem across time (diachronic) and at an instant (synchronic) [Lowe] |
7715 | Mentalese isn't a language, because it isn't conventional, or a means of public communication [Lowe] |
7722 | If meaning is mental pictures, explain "the cat (or dog!) is NOT on the mat" [Lowe] |
5041 | God does everything in a perfect way, and never acts contrary to reason [Leibniz] |