20 ideas
18901 | Truthmakers are facts 'of' a domain, not something 'in' the domain [Sommers] |
18904 | 'Predicable' terms come in charged pairs, with one the negation of the other [Sommers, by Engelbretsen] |
18895 | Logic which maps ordinary reasoning must be transparent, and free of variables [Sommers] |
14970 | Normal system K has five axioms and rules [Cresswell] |
14971 | D is valid on every serial frame, but not where there are dead ends [Cresswell] |
14972 | S4 has 14 modalities, and always reduces to a maximum of three modal operators [Cresswell] |
14973 | In S5 all the long complex modalities reduce to just three, and their negations [Cresswell] |
14976 | Reject the Barcan if quantifiers are confined to worlds, and different things exist in other worlds [Cresswell] |
18897 | Predicate logic has to spell out that its identity relation '=' is an equivalent relation [Sommers] |
18893 | Translating into quantificational idiom offers no clues as to how ordinary thinkers reason [Sommers] |
18903 | Sommers promotes the old idea that negation basically refers to terms [Sommers, by Engelbretsen] |
18894 | Predicates form a hierarchy, from the most general, down to names at the bottom [Sommers] |
18900 | Unfortunately for realists, modern logic cannot say that some fact exists [Sommers] |
14974 | A relation is 'Euclidean' if aRb and aRc imply bRc [Cresswell] |
14975 | A de dicto necessity is true in all worlds, but not necessarily of the same thing in each world [Cresswell] |
7401 | Heat and colour don't exist, so cannot mislead about the external world [Galileo, by Tuck] |
5454 | Tastes, odours and colours only reside in consciousness, and would disappear with creatures [Galileo] |
16560 | Galileo introduced geometrico-mechanical explanation, based on Archimedes [Galileo, by Machamer/Darden/Craver] |
18898 | In standard logic, names are the only way to refer [Sommers] |
3645 | To understand the universe mathematics is essential [Galileo] |