39 ideas
3123 | Science is in the business of carving nature at the joints [Segal] |
3125 | Psychology studies the way rationality links desires and beliefs to causality [Segal] |
21752 | Prior to Gödel we thought truth in mathematics consisted in provability [Gödel, by Quine] |
17835 | Gödel show that the incompleteness of set theory was a necessity [Gödel, by Hallett,M] |
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] |
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] |
10132 | There can be no single consistent theory from which all mathematical truths can be derived [Gödel, by George/Velleman] |
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] |
8747 | Realists are happy with impredicative definitions, which describe entities in terms of other existing entities [Gödel, by Shapiro] |
14979 | Being alone doesn't guarantee intrinsic properties; 'being alone' is itself extrinsic [Lewis, by Sider] |
15454 | Extrinsic properties come in degrees, with 'brother' less extrinsic than 'sibling' [Lewis] |
15455 | Total intrinsic properties give us what a thing is [Lewis] |
3105 | Is 'Hesperus = Phosphorus' metaphysically necessary, but not logically or epistemologically necessary? [Segal] |
3106 | If claims of metaphysical necessity are based on conceivability, we should be cautious [Segal] |
3113 | The success and virtue of an explanation do not guarantee its truth [Segal] |
3192 | Basic logic can be done by syntax, with no semantics [Gödel, by Rey] |
3112 | Folk psychology is ridiculously dualist in its assumptions [Segal] |
3108 | If 'water' has narrow content, it refers to both H2O and XYZ [Segal] |
3110 | Humans are made of H2O, so 'twins' aren't actually feasible [Segal] |
3124 | Externalists can't assume old words refer to modern natural kinds [Segal] |
3117 | Concepts can survive a big change in extension [Segal] |
3104 | Must we relate to some diamonds to understand them? [Segal] |
3103 | Maybe content involves relations to a language community [Segal] |
3111 | Externalism can't explain concepts that have no reference [Segal] |
3109 | If content is external, so are beliefs and desires [Segal] |
3116 | Maybe experts fix content, not ordinary users [Segal] |
3121 | If content is narrow, my perfect twin shares my concepts [Segal] |
3118 | If thoughts ARE causal, we can't explain how they cause things [Segal] |
3119 | Even 'mass' cannot be defined in causal terms [Segal] |