98 ideas
| 2797 | As coherence expands its interrelations become steadily tighter, culminating only in necessary truth [Dancy,J] |
| 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] |
| 2768 | The correspondence theory also has the problem that two sets of propositions might fit the facts equally well [Dancy,J] |
| 2765 | Rescher says that if coherence requires mutual entailment, this leads to massive logical redundancy [Dancy,J] |
| 2769 | If one theory is held to be true, all the other theories appear false, because they can't be added to the true one [Dancy,J] |
| 2766 | Even with a tight account of coherence, there is always the possibility of more than one set of coherent propositions [Dancy,J] |
| 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] |
| 3198 | Gödel showed that arithmetic is either incomplete or inconsistent [Gödel, by Rey] |
| 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] |
| 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] |
| 2781 | Realism says that most perceived objects exist, and have some of their perceived properties [Dancy,J] |
| 2745 | A pupil who lacks confidence may clearly know something but not be certain of it [Dancy,J] |
| 2755 | If senses are fallible, then being open to correction is an epistemological virtue [Dancy,J] |
| 5677 | Naďve direct realists hold that objects retain all of their properties when unperceived [Dancy,J] |
| 5678 | Scientific direct realism says we know some properties of objects directly [Dancy,J] |
| 5681 | Maybe we are forced from direct into indirect realism by the need to explain perceptual error [Dancy,J] |
| 5682 | Internal realism holds that we perceive physical objects via mental objects [Dancy,J] |
| 5683 | Indirect realism depends on introspection, the time-lag, illusions, and neuroscience [Dancy,J, by PG] |
| 2778 | Phenomenalism includes possible experiences, but idealism only refers to actual experiences [Dancy,J] |
| 5684 | Eliminative idealists say there are no objects; reductive idealists say objects exist as complex experiences [Dancy,J] |
| 2777 | Extreme solipsism only concerns current experience, but it might include past and future [Dancy,J] |
| 2794 | Knowing that a cow is not a horse seems to be a synthetic a priori truth [Dancy,J] |
| 2780 | Perception is either direct realism, indirect realism, or phenomenalism [Dancy,J] |
| 5679 | We can't grasp the separation of quality types, or what a primary-quality world would be like [Dancy,J] |
| 5680 | For direct realists the secondary and primary qualities seem equally direct [Dancy,J] |
| 2782 | We can be looking at distant stars which no longer actually exist [Dancy,J] |
| 2775 | It is not clear from the nature of sense data whether we should accept them as facts [Dancy,J] |
| 2784 | Appearances don't guarantee reality, unless the appearance is actually caused by the reality [Dancy,J] |
| 2785 | Perceptual beliefs may be directly caused, but generalisations can't be [Dancy,J] |
| 2788 | If perception and memory are indirect, then two things stand between mind and reality [Dancy,J] |
| 2787 | Memories aren't directly about the past, because time-lags and illusions suggest representation [Dancy,J] |
| 2791 | Phenomenalism about memory denies the past, or reduces it to present experience [Dancy,J] |
| 2790 | I can remember plans about the future, and images aren't essential (2+3=5) [Dancy,J] |
| 2754 | Foundations are justified by non-beliefs, or circularly, or they need no justification [Dancy,J] |
| 2749 | For internalists we must actually know that the fact caused the belief [Dancy,J] |
| 2770 | Internalists tend to favour coherent justification, but not the coherence theory of truth [Dancy,J] |
| 2752 | Foundationalism requires inferential and non-inferential justification [Dancy,J] |
| 2771 | Foundationalists must accept not only the basic beliefs, but also rules of inference for further progress [Dancy,J] |
| 2756 | If basic beliefs can be false, falsehood in non-basic beliefs might by a symptom [Dancy,J] |
| 2753 | Beliefs can only be infallible by having almost no content [Dancy,J] |
| 2773 | Coherentism gives a possible justification of induction, and opposes scepticism [Dancy,J] |
| 2779 | Idealists must be coherentists, but coherentists needn't be idealists [Dancy,J] |
| 2786 | For coherentists justification and truth are not radically different things [Dancy,J] |
| 2767 | If it is empirical propositions which have to be coherent, this eliminates coherent fiction [Dancy,J] |
| 2776 | Externalism could even make belief unnecessary (e.g. in animals) [Dancy,J] |
| 2746 | How can a causal theory of justification show that all men die? [Dancy,J] |
| 2747 | Causal theories don't allow for errors in justification [Dancy,J] |
| 2772 | Coherentism moves us towards a more social, shared view of knowledge [Dancy,J] |
| 3061 | Anaxarchus said that he was not even sure that he knew nothing [Anaxarchus, by Diog. Laertius] |
| 2743 | What is the point of arguing against knowledge, if being right undermines your own argument? [Dancy,J] |
| 2751 | Probabilities can only be assessed relative to some evidence [Dancy,J] |
| 2757 | The argument from analogy rests on one instance alone [Dancy,J] |
| 2758 | You can't separate mind and behaviour, as the analogy argument attempts [Dancy,J] |
| 3192 | Basic logic can be done by syntax, with no semantics [Gödel, by Rey] |
| 2744 | Verificationism (the 'verification principle') is an earlier form of anti-realism [Dancy,J] |
| 2760 | Logical positivism implies foundationalism, by dividing weak from strong verifications [Dancy,J] |
| 2761 | If the meanings of sentences depend on other sentences, how did we learn language? [Dancy,J] |
| 2763 | There is an indeterminacy in juggling apparent meanings against probable beliefs [Dancy,J] |
| 2762 | Charity makes native beliefs largely true, and Humanity makes them similar to ours [Dancy,J] |
| 7260 | If there are intuited moral facts, why should we care about them? [Dancy,J] |
| 7261 | Internalists say that moral intuitions are motivating; externalist say a desire is also needed [Dancy,J] |
| 7262 | Obviously judging an action as wrong gives us a reason not to do it [Dancy,J] |
| 7265 | Moral facts are not perceived facts, but perceived reasons for judgements [Dancy,J] |
| 18681 | The base for values has grounds, catalysts and intensifiers [Dancy,J, by Orsi] |