63 ideas
6887 | Linguistic philosophy approaches problems by attending to actual linguistic usage [Mautner] |
6881 | Analytic philosophy studies the unimportant, and sharpens tools instead of using them [Mautner] |
5439 | The 'hermeneutic circle' says parts and wholes are interdependent, and so cannot be interpreted [Mautner] |
15663 | Adorno and Horkheimer subjected the Enlightenment to 'critical theory' analysis [Adorno/Horkheimer, by Finlayson] |
17774 | Definitions make our intuitions mathematically useful [Mayberry] |
9959 | 'Real' definitions give the essential properties of things under a concept [Mautner] |
9961 | 'Contextual definitions' replace whole statements, not just expressions [Mautner] |
9958 | Recursive definition defines each instance from a previous instance [Mautner] |
9960 | A stipulative definition lays down that an expression is to have a certain meaning [Mautner] |
9957 | Ostensive definitions point to an object which an expression denotes [Mautner] |
17773 | Proof shows that it is true, but also why it must be true [Mayberry] |
6219 | The fallacy of composition is the assumption that what is true of the parts is true of the whole [Mautner] |
6888 | Fuzzy logic is based on the notion that there can be membership of a set to some degree [Mautner] |
17795 | Set theory can't be axiomatic, because it is needed to express the very notion of axiomatisation [Mayberry] |
17796 | There is a semi-categorical axiomatisation of set-theory [Mayberry] |
17800 | The misnamed Axiom of Infinity says the natural numbers are finite in size [Mayberry] |
17801 | The set hierarchy doesn't rely on the dubious notion of 'generating' them [Mayberry] |
17803 | Limitation of size is part of the very conception of a set [Mayberry] |
17786 | The mainstream of modern logic sees it as a branch of mathematics [Mayberry] |
17788 | First-order logic only has its main theorems because it is so weak [Mayberry] |
17791 | Only second-order logic can capture mathematical structure up to isomorphism [Mayberry] |
6877 | Entailment is logical requirement; it may be not(p and not-q), but that has problems [Mautner] |
6880 | Strict implication says false propositions imply everything, and everything implies true propositions [Mautner] |
6879 | 'Material implication' is defined as 'not(p and not-q)', but seems to imply a connection between p and q [Mautner] |
6878 | A person who 'infers' draws the conclusion, but a person who 'implies' leaves it to the audience [Mautner] |
6889 | Vagueness seems to be inconsistent with the view that every proposition is true or false [Mautner] |
6890 | Quantifiers turn an open sentence into one to which a truth-value can be assigned [Mautner] |
17787 | Big logic has one fixed domain, but standard logic has a domain for each interpretation [Mayberry] |
17790 | No Löwenheim-Skolem logic can axiomatise real analysis [Mayberry] |
17779 | 'Classificatory' axioms aim at revealing similarity in morphology of structures [Mayberry] |
17778 | Axiomatiation relies on isomorphic structures being essentially the same [Mayberry] |
17780 | 'Eliminatory' axioms get rid of traditional ideal and abstract objects [Mayberry] |
17789 | No logic which can axiomatise arithmetic can be compact or complete [Mayberry] |
17784 | Real numbers can be eliminated, by axiom systems for complete ordered fields [Mayberry] |
17782 | Greek quantities were concrete, and ratio and proportion were their science [Mayberry] |
17781 | Real numbers were invented, as objects, to simplify and generalise 'quantity' [Mayberry] |
17799 | Cantor's infinite is an absolute, of all the sets or all the ordinal numbers [Mayberry] |
17797 | Cantor extended the finite (rather than 'taming the infinite') [Mayberry] |
17775 | If proof and definition are central, then mathematics needs and possesses foundations [Mayberry] |
17776 | The ultimate principles and concepts of mathematics are presumed, or grasped directly [Mayberry] |
17777 | Foundations need concepts, definition rules, premises, and proof rules [Mayberry] |
17804 | Axiom theories can't give foundations for mathematics - that's using axioms to explain axioms [Mayberry] |
17792 | 1st-order PA is only interesting because of results which use 2nd-order PA [Mayberry] |
17793 | It is only 2nd-order isomorphism which suggested first-order PA completeness [Mayberry] |
17794 | Set theory is not just first-order ZF, because that is inadequate for mathematics [Mayberry] |
17802 | We don't translate mathematics into set theory, because it comes embodied in that way [Mayberry] |
17805 | Set theory is not just another axiomatised part of mathematics [Mayberry] |
17785 | Real numbers as abstracted objects are now treated as complete ordered fields [Mayberry] |
6882 | Counterfactuals presuppose a belief (or a fact) that the condition is false [Mautner] |
6886 | Counterfactuals are not true, they are merely valid [Mautner] |
6885 | Counterfactuals are true if in every world close to actual where p is the case, q is also the case [Mautner] |
6884 | Counterfactuals say 'If it had been, or were, p, then it would be q' [Mautner] |
6883 | Maybe counterfactuals are only true if they contain valid inference from premisses [Mautner] |
5449 | Essentialism is often identified with belief in 'de re' necessary truths [Mautner] |
6898 | Fallibilism is the view that all knowledge-claims are provisional [Mautner] |
6452 | 'Sense-data' arrived in 1910, but it denotes ideas in Locke, Berkeley and Hume [Mautner] |
4783 | Observing lots of green x can confirm 'all x are green' or 'all x are grue', where 'grue' is arbitrary [Mautner, by PG] |
4782 | 'All x are y' is equivalent to 'all non-y are non-x', so observing paper is white confirms 'ravens are black' [Mautner, by PG] |
6899 | The references of indexicals ('there', 'now', 'I') depend on the circumstances of utterance [Mautner] |
6896 | Double effect is the distinction between what is foreseen and what is intended [Mautner] |
6897 | Double effect acts need goodness, unintended evil, good not caused by evil, and outweighing [Mautner] |
20572 | De Sade said it was impossible to rationally argue against murder [Adorno/Horkheimer] |
5452 | 'Essentialism' is opposed to existentialism, and claims there is a human nature [Mautner] |