59 ideas
8013 | In the Reformation, morality became unconditional but irrational, individually autonomous, and secular [MacIntyre] |
8021 | The Levellers and the Diggers mark a turning point in the history of morality [MacIntyre] |
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] |
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] |
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] |
10888 | Sets can be defined by 'enumeration', or by 'abstraction' (based on a property) [Zalabardo] |
10889 | The 'Cartesian Product' of two sets relates them by pairing every element with every element [Zalabardo] |
10890 | A 'partial ordering' is reflexive, antisymmetric and transitive [Zalabardo] |
10886 | Determinacy: an object is either in a set, or it isn't [Zalabardo] |
10887 | Specification: Determinate totals of objects always make a set [Zalabardo] |
10897 | A first-order 'sentence' is a formula with no free variables [Zalabardo] |
10893 | Γ |= φ for sentences if φ is true when all of Γ is true [Zalabardo] |
10899 | Γ |= φ if φ is true when all of Γ is true, for all structures and interpretations [Zalabardo] |
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] |
10896 | Propositional logic just needs ¬, and one of ∧, ∨ and → [Zalabardo] |
6890 | Quantifiers turn an open sentence into one to which a truth-value can be assigned [Mautner] |
10898 | The semantics shows how truth values depend on instantiations of properties and relations [Zalabardo] |
10902 | We can do semantics by looking at given propositions, or by building new ones [Zalabardo] |
10892 | We make a truth assignment to T and F, which may be true and false, but merely differ from one another [Zalabardo] |
10895 | 'Logically true' (|= φ) is true for every truth-assignment [Zalabardo] |
10900 | Logically true sentences are true in all structures [Zalabardo] |
10894 | A sentence-set is 'satisfiable' if at least one truth-assignment makes them all true [Zalabardo] |
10901 | Some formulas are 'satisfiable' if there is a structure and interpretation that makes them true [Zalabardo] |
10903 | A structure models a sentence if it is true in the model, and a set of sentences if they are all true in the model [Zalabardo] |
10891 | If a set is defined by induction, then proof by induction can be applied to it [Zalabardo] |
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] |
8006 | When Aristotle speaks of soul he means something like personality [MacIntyre] |
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] |
5452 | 'Essentialism' is opposed to existentialism, and claims there is a human nature [Mautner] |
8002 | Sophists don't distinguish a person outside one social order from someone outside all order [MacIntyre] |
8012 | The value/fact logical gulf is misleading, because social facts involve values [MacIntyre] |
8005 | 'Happiness' is a bad translation of 'eudaimonia', which includes both behaving and faring well [MacIntyre] |
8001 | 'Dikaiosune' is justice, but also fairness and personal integrity [MacIntyre] |
8023 | My duties depend on my identity, which depends on my social relations [MacIntyre] |
8022 | I am naturally free if I am not tied to anyone by a contract [MacIntyre] |
8031 | Fans of natural rights or laws can't agree on what the actual rights or laws are [MacIntyre] |
8008 | The Bible is a story about God in which humans are incidental characters [MacIntyre] |