51 ideas
| 5784 | In its primary and formal sense, 'true' applies to propositions, not beliefs [Russell] |
| 5777 | The truth or falsehood of a belief depends upon a fact to which the belief 'refers' [Russell] |
| 5783 | Propositions of existence, generalities, disjunctions and hypotheticals make correspondence tricky [Russell] |
| 10888 | Sets can be defined by 'enumeration', or by 'abstraction' (based on a property) [Zalabardo] |
| 10889 | The 'Cartesian Product' of two sets relates them by pairing every element with every element [Zalabardo] |
| 10890 | A 'partial ordering' is reflexive, antisymmetric and transitive [Zalabardo] |
| 10886 | Determinacy: an object is either in a set, or it isn't [Zalabardo] |
| 10887 | Specification: Determinate totals of objects always make a set [Zalabardo] |
| 10897 | A first-order 'sentence' is a formula with no free variables [Zalabardo] |
| 10893 | Γ |= φ for sentences if φ is true when all of Γ is true [Zalabardo] |
| 10899 | Γ |= φ if φ is true when all of Γ is true, for all structures and interpretations [Zalabardo] |
| 10896 | Propositional logic just needs ¬, and one of ∧, ∨ and → [Zalabardo] |
| 10898 | The semantics shows how truth values depend on instantiations of properties and relations [Zalabardo] |
| 10902 | We can do semantics by looking at given propositions, or by building new ones [Zalabardo] |
| 10892 | We make a truth assignment to T and F, which may be true and false, but merely differ from one another [Zalabardo] |
| 10895 | 'Logically true' (|= φ) is true for every truth-assignment [Zalabardo] |
| 10900 | Logically true sentences are true in all structures [Zalabardo] |
| 10894 | A sentence-set is 'satisfiable' if at least one truth-assignment makes them all true [Zalabardo] |
| 10901 | Some formulas are 'satisfiable' if there is a structure and interpretation that makes them true [Zalabardo] |
| 10903 | A structure models a sentence if it is true in the model, and a set of sentences if they are all true in the model [Zalabardo] |
| 10891 | If a set is defined by induction, then proof by induction can be applied to it [Zalabardo] |
| 5780 | The three questions about belief are its contents, its success, and its character [Russell] |
| 17979 | Research shows perceptual discrimination is sharper at category boundaries [Murphy] |
| 18690 | Induction is said to just compare properties of categories, but the type of property also matters [Murphy] |
| 5778 | If we object to all data which is 'introspective' we will cease to believe in toothaches [Russell] |
| 5779 | There are distinct sets of psychological and physical causal laws [Russell] |
| 17980 | The main theories of concepts are exemplar, prototype and knowledge [Murphy] |
| 17973 | The theoretical and practical definitions for the classical view are very hard to find [Murphy] |
| 17969 | The classical definitional approach cannot distinguish typical and atypical category members [Murphy] |
| 17970 | Classical concepts follow classical logic, but concepts in real life don't work that way [Murphy] |
| 17971 | Classical concepts are transitive hierarchies, but actual categories may be intransitive [Murphy] |
| 17972 | The classical core is meant to be the real concept, but actually seems unimportant [Murphy] |
| 17975 | There is no 'ideal' bird or dog, and prototypes give no information about variability [Murphy] |
| 17976 | Prototypes are unified representations of the entire category (rather than of members) [Murphy] |
| 18691 | The prototype theory uses observed features, but can't include their construction [Murphy] |
| 17983 | The prototype theory handles hierarchical categories and combinations of concepts well [Murphy] |
| 17985 | Prototypes theory of concepts is best, as a full description with weighted typical features [Murphy] |
| 17986 | Learning concepts is forming prototypes with a knowledge structure [Murphy] |
| 17974 | The most popular theories of concepts are based on prototypes or exemplars [Murphy] |
| 17977 | The exemplar view of concepts says 'dogs' is the set of dogs I remember [Murphy] |
| 17982 | Exemplar theory struggles with hierarchical classification and with induction [Murphy] |
| 17981 | Children using knowing and essentialist categories doesn't fit the exemplar view [Murphy] |
| 17984 | Conceptual combination must be compositional, and can't be built up from exemplars [Murphy] |
| 17987 | The concept of birds from exemplars must also be used in inductions about birds [Murphy] |
| 17978 | We do not learn concepts in isolation, but as an integrated part of broader knowledge [Murphy] |
| 18687 | Concepts with familiar contents are easier to learn [Murphy] |
| 18688 | Some knowledge is involved in instant use of categories, other knowledge in explanations [Murphy] |
| 18689 | People categorise things consistent with their knowledge, even rejecting some good evidence [Murphy] |
| 5781 | Our important beliefs all, if put into words, take the form of propositions [Russell] |
| 5782 | A proposition expressed in words is a 'word-proposition', and one of images an 'image-proposition' [Russell] |
| 5776 | A proposition is what we believe when we believe truly or falsely [Russell] |