65 ideas
17892 | For clear questions posed by reason, reason can also find clear answers [Gödel] |
10041 | Impredicative Definitions refer to the totality to which the object itself belongs [Gödel] |
21752 | Prior to Gödel we thought truth in mathematics consisted in provability [Gödel, by Quine] |
17751 | Gödel proved the completeness of first order predicate logic in 1930 [Gödel, by Walicki] |
8679 | We perceive the objects of set theory, just as we perceive with our senses [Gödel] |
17835 | Gödel show that the incompleteness of set theory was a necessity [Gödel, by Hallett,M] |
9942 | Gödel proved the classical relative consistency of the axiom V = L [Gödel, by Putnam] |
21716 | In simple type theory the axiom of Separation is better than Reducibility [Gödel, by Linsky,B] |
9188 | Gödel proved that first-order logic is complete, and second-order logic incomplete [Gödel, by Dummett] |
10035 | Mathematical Logic is a non-numerical branch of mathematics, and the supreme science [Gödel] |
10042 | Reference to a totality need not refer to a conjunction of all its elements [Gödel] |
10620 | Originally truth was viewed with total suspicion, and only demonstrability was accepted [Gödel] |
17886 | The limitations of axiomatisation were revealed by the incompleteness theorems [Gödel, by Koellner] |
10071 | Second Incompleteness: nice theories can't prove their own consistency [Gödel, by Smith,P] |
19123 | If soundness can't be proved internally, 'reflection principles' can be added to assert soundness [Gödel, by Halbach/Leigh] |
17883 | Gödel's Theorems did not refute the claim that all good mathematical questions have answers [Gödel, by Koellner] |
10621 | Gödel's First Theorem sabotages logicism, and the Second sabotages Hilbert's Programme [Smith,P on Gödel] |
17888 | The undecidable sentence can be decided at a 'higher' level in the system [Gödel] |
10038 | A logical system needs a syntactical survey of all possible expressions [Gödel] |
18062 | Set-theory paradoxes are no worse than sense deception in physics [Gödel] |
10132 | There can be no single consistent theory from which all mathematical truths can be derived [Gödel, by George/Velleman] |
10046 | The generalized Continuum Hypothesis asserts a discontinuity in cardinal numbers [Gödel] |
10868 | The Continuum Hypothesis is not inconsistent with the axioms of set theory [Gödel, by Clegg] |
13517 | If set theory is consistent, we cannot refute or prove the Continuum Hypothesis [Gödel, by Hart,WD] |
17885 | Gödel eventually hoped for a generalised completeness theorem leaving nothing undecidable [Gödel, by Koellner] |
10614 | The real reason for Incompleteness in arithmetic is inability to define truth in a language [Gödel] |
10072 | First Incompleteness: arithmetic must always be incomplete [Gödel, by Smith,P] |
9590 | Arithmetical truth cannot be fully and formally derived from axioms and inference rules [Gödel, by Nagel/Newman] |
3198 | Gödel showed that arithmetic is either incomplete or inconsistent [Gödel, by Rey] |
11069 | Gödel's Second says that semantic consequence outruns provability [Gödel, by Hanna] |
10118 | First Incompleteness: a decent consistent system is syntactically incomplete [Gödel, by George/Velleman] |
10122 | Second Incompleteness: a decent consistent system can't prove its own consistency [Gödel, by George/Velleman] |
10611 | There is a sentence which a theory can show is true iff it is unprovable [Gödel, by Smith,P] |
10867 | 'This system can't prove this statement' makes it unprovable either way [Gödel, by Clegg] |
10039 | Some arithmetical problems require assumptions which transcend arithmetic [Gödel] |
10043 | Mathematical objects are as essential as physical objects are for perception [Gödel] |
10271 | Basic mathematics is related to abstract elements of our empirical ideas [Gödel] |
10045 | Impredicative definitions are admitted into ordinary mathematics [Gödel] |
8747 | Realists are happy with impredicative definitions, which describe entities in terms of other existing entities [Gödel, by Shapiro] |
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] |
3192 | Basic logic can be done by syntax, with no semantics [Gödel, by Rey] |
17980 | The main theories of concepts are exemplar, prototype and knowledge [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] |
17973 | The theoretical and practical definitions for the classical view are very hard to find [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] |
17977 | The exemplar view of concepts says 'dogs' is the set of dogs I remember [Murphy] |
17981 | Children using knowing and essentialist categories doesn't fit the exemplar view [Murphy] |
17982 | Exemplar theory struggles with hierarchical classification and with induction [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] |
17974 | The most popular theories of concepts are based on prototypes or exemplars [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] |
3031 | The greatest good is not the achievement of desire, but to desire what is proper [Menedemus, by Diog. Laertius] |