43 ideas
| 19066 | Philosophy aims to understand the world, through ordinary experience and science [Dummett] |
| 19067 | A successful proof requires recognition of truth at every step [Dummett] |
| 15879 | The Square of Opposition has two contradictory pairs, one contrary pair, and one sub-contrary pair [Harré] |
| 19060 | Truth-tables are dubious in some cases, and may be a bad way to explain connective meaning [Dummett] |
| 11066 | Deduction is justified by the semantics of its metalanguage [Dummett, by Hanna] |
| 19058 | Syntactic consequence is positive, for validity; semantic version is negative, with counterexamples [Dummett] |
| 15891 | Traditional quantifiers combine ordinary language generality and ontology assumptions [Harré] |
| 15878 | Some quantifiers, such as 'any', rule out any notion of order within their range [Harré] |
| 19063 | Beth trees show semantics for intuitionistic logic, in terms of how truth has been established [Dummett] |
| 19059 | In standard views you could replace 'true' and 'false' with mere 0 and 1 [Dummett] |
| 19062 | Classical two-valued semantics implies that meaning is grasped through truth-conditions [Dummett] |
| 14212 | A consistent theory just needs one model; isomorphic versions will do too, and large domains provide those [Lewis] |
| 19065 | Soundness and completeness proofs test the theory of meaning, rather than the logic theory [Dummett] |
| 14213 | Anti-realists see the world as imaginary, or lacking joints, or beyond reference, or beyond truth [Lewis] |
| 15874 | Scientific properties are not observed qualities, but the dispositions which create them [Harré] |
| 14210 | A gerrymandered mereological sum can be a mess, but still have natural joints [Lewis] |
| 15884 | Laws of nature remain the same through any conditions, if the underlying mechanisms are unchanged [Harré] |
| 15880 | In physical sciences particular observations are ordered, but in biology only the classes are ordered [Harré] |
| 15869 | Reports of experiments eliminate the experimenter, and present results as the behaviour of nature [Harré] |
| 15881 | We can save laws from counter-instances by treating the latter as analytic definitions [Harré] |
| 15882 | Since there are three different dimensions for generalising laws, no one system of logic can cover them [Harré] |
| 15888 | The grue problem shows that natural kinds are central to science [Harré] |
| 15887 | 'Grue' introduces a new causal hypothesis - that emeralds can change colour [Harré] |
| 15889 | It is because ravens are birds that their species and their colour might be connected [Harré] |
| 15890 | Non-black non-ravens just aren't part of the presuppositions of 'all ravens are black' [Harré] |
| 19061 | An explanation is often a deduction, but that may well beg the question [Dummett] |
| 15885 | The necessity of Newton's First Law derives from the nature of material things, not from a mechanism [Harré] |
| 15868 | Idealisation idealises all of a thing's properties, but abstraction leaves some of them out [Harré] |
| 19064 | Holism is not a theory of meaning; it is the denial that a theory of meaning is possible [Dummett] |
| 14215 | Causal theories of reference make errors in reference easy [Lewis] |
| 14209 | Descriptive theories remain part of the theory of reference (with seven mild modifications) [Lewis] |
| 15886 | Science rests on the principle that nature is a hierarchy of natural kinds [Harré] |
| 15864 | Classification is just as important as laws in natural science [Harré] |
| 15865 | Newton's First Law cannot be demonstrated experimentally, as that needs absence of external forces [Harré] |
| 15862 | Laws can come from data, from theory, from imagination and concepts, or from procedures [Harré] |
| 15870 | Are laws of nature about events, or types and universals, or dispositions, or all three? [Harré] |
| 15871 | Are laws about what has or might happen, or do they also cover all the possibilities? [Harré] |
| 15876 | Maybe laws of nature are just relations between properties? [Harré] |
| 15860 | We take it that only necessary happenings could be laws [Harré] |
| 15867 | Laws describe abstract idealisations, not the actual mess of nature [Harré] |
| 15872 | Must laws of nature be universal, or could they be local? [Harré] |
| 15892 | Laws of nature state necessary connections of things, events and properties, based on models of mechanisms [Harré] |
| 15875 | In counterfactuals we keep substances constant, and imagine new situations for them [Harré] |