34 ideas
| 10282 | Logic is the study of sound argument, or of certain artificial languages (or applying the latter to the former) [Hodges,W] |
| 10283 | A formula needs an 'interpretation' of its constants, and a 'valuation' of its variables [Hodges,W] |
| 10284 | There are three different standard presentations of semantics [Hodges,W] |
| 10285 | I |= φ means that the formula φ is true in the interpretation I [Hodges,W] |
| 10288 | Down Löwenheim-Skolem: if a countable language has a consistent theory, that has a countable model [Hodges,W] |
| 10289 | Up Löwenheim-Skolem: if infinite models, then arbitrarily large models [Hodges,W] |
| 10287 | If a first-order theory entails a sentence, there is a finite subset of the theory which entails it [Hodges,W] |
| 10286 | A 'set' is a mathematically well-behaved class [Hodges,W] |
| 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] |
| 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] |
| 1748 | Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius] |
| 5989 | Archelaus said life began in a primeval slime [Archelaus, by Schofield] |