40 ideas
20981 | What justifies reliance on reason? Is it just a tool? Why is it better than blind belief? [Sen] |
20982 | In politics and ethics, scrutiny from different perspectives is essential for objectivity [Sen] |
10476 | The idea that groups of concepts could be 'implicitly defined' was abandoned [Hodges,W] |
10282 | Logic is the study of sound argument, or of certain artificial languages (or applying the latter to the former) [Hodges,W] |
10478 | Since first-order languages are complete, |= and |- have the same meaning [Hodges,W] |
10477 | |= in model-theory means 'logical consequence' - it holds in all models [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] |
10474 | |= should be read as 'is a model for' or 'satisfies' [Hodges,W] |
10473 | Model theory studies formal or natural language-interpretation using set-theory [Hodges,W] |
10475 | A 'structure' is an interpretation specifying objects and classes of quantification [Hodges,W] |
10481 | Models in model theory are structures, not sets of descriptions [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] |
10480 | First-order logic can't discriminate between one infinite cardinal and another [Hodges,W] |
10286 | A 'set' is a mathematically well-behaved class [Hodges,W] |
20653 | Six reduction levels: groups, lives, cells, molecules, atoms, particles [Putnam/Oppenheim, by Watson] |
20990 | Rationality is conformity to reasons that can be sustained even after scrutiny [Sen] |
21005 | A human right is not plausible if public scrutiny might reject it [Sen] |
20983 | The original position insures that the agreements reached are fair [Sen] |
20987 | The veil of ignorance encourages neutral interests, but not a wider view of values [Sen] |
20984 | A social contract limits the pursuit of justice to members of a single society [Sen] |
20986 | A person's voice may count because of their interests, or because of their good sense [Sen] |
21001 | Famines tend to be caused by authoritarian rule [Sen] |
21002 | Effective democracy needs tolerant values [Sen] |
20999 | Democracy as 'government by discussion' now has wide support [Sen] |
20979 | Democracy needs more than some institutions; diverse sections of the people must be heard [Sen] |
20993 | Eradicating smallpox does not impoverish nature [Sen] |
20995 | Capabilities are part of freedom, involving real opportunities [Sen] |
20998 | Freedom can involve capabilities, independence and non-interference [Sen] |
20997 | The need for equality among people arises from impartiality and objectivity [Sen] |
20996 | All modern theories of justice demand equality of something [Sen] |
20988 | Freedom from torture or terrorist attacks is independent of citizenship [Sen] |
20980 | You don't need a complete theory of justice to see that slavery is wrong [Sen] |
20978 | Practical justice concerns not only ideals, but ways to achieve them [Sen] |
20985 | Our institutions should promote justice, rather than embodying it [Sen] |
20994 | We must focus on removing manifest injustice, not just try to design a perfect society [Sen] |
21000 | If justice needs public reasoning, which needs democracy, then justice and democracy are linked [Sen] |