45 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] |
13838 | A decent modern definition should always imply a semantics [Hacking] |
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] |
13834 | Gentzen's Cut Rule (or transitivity of deduction) is 'If A |- B and B |- C, then A |- C' [Hacking] |
13835 | Only Cut reduces complexity, so logic is constructive without it, and it can be dispensed with [Hacking] |
13833 | 'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking] |
6888 | Fuzzy logic is based on the notion that there can be membership of a set to some degree [Mautner] |
13845 | The various logics are abstractions made from terms like 'if...then' in English [Hacking] |
13840 | First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking] |
13844 | A limitation of first-order logic is that it cannot handle branching quantifiers [Hacking] |
13842 | Second-order completeness seems to need intensional entities and possible worlds [Hacking] |
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] |
13837 | With a pure notion of truth and consequence, the meanings of connectives are fixed syntactically [Hacking] |
13839 | Perhaps variables could be dispensed with, by arrows joining places in the scope of quantifiers [Hacking] |
6890 | Quantifiers turn an open sentence into one to which a truth-value can be assigned [Mautner] |
13843 | If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking] |
7557 | To solve Zeno's paradox, reject the axiom that the whole has more terms than the parts [Russell] |
10059 | In mathematic we are ignorant of both subject-matter and truth [Russell] |
7556 | A collection is infinite if you can remove some terms without diminishing its number [Russell] |
6884 | Counterfactuals say 'If it had been, or were, p, then it would be q' [Mautner] |
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] |
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] |
7554 | Self-evidence is often a mere will-o'-the-wisp [Russell] |
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] |
5452 | 'Essentialism' is opposed to existentialism, and claims there is a human nature [Mautner] |