55 ideas
1798 | He studied philosophy by suspending his judgement on everything [Pyrrho, by Diog. Laertius] |
19199 | Some say metaphysics is a highly generalised empirical study of objects [Tarski] |
6118 | Philosophy is logical analysis, followed by synthesis [Russell] |
19193 | Disputes that fail to use precise scientific terminology are all meaningless [Tarski] |
6116 | A logical language would show up the fallacy of inferring reality from ordinary language [Russell] |
6117 | Philosophy should be built on science, to reduce error [Russell] |
1800 | Sceptics say reason is only an instrument, because reason can only be attacked with reason [Pyrrho, by Diog. Laertius] |
19179 | For a definition we need the words or concepts used, the rules, and the structure of the language [Tarski] |
19178 | Definitions of truth should not introduce a new version of the concept, but capture the old one [Tarski] |
19177 | A definition of truth should be materially adequate and formally correct [Tarski] |
19186 | A rigorous definition of truth is only possible in an exactly specified language [Tarski] |
19194 | We may eventually need to split the word 'true' into several less ambiguous terms [Tarski] |
19180 | It is convenient to attach 'true' to sentences, and hence the language must be specified [Tarski] |
19181 | In the classical concept of truth, 'snow is white' is true if snow is white [Tarski] |
19196 | Scheme (T) is not a definition of truth [Tarski] |
19183 | Each interpreted T-sentence is a partial definition of truth; the whole definition is their conjunction [Tarski] |
19182 | Use 'true' so that all T-sentences can be asserted, and the definition will then be 'adequate' [Tarski] |
19198 | We don't give conditions for asserting 'snow is white'; just that assertion implies 'snow is white' is true [Tarski] |
19184 | The best truth definition involves other semantic notions, like satisfaction (relating terms and objects) [Tarski] |
19191 | Specify satisfaction for simple sentences, then compounds; true sentences are satisfied by all objects [Tarski] |
19188 | We can't use a semantically closed language, or ditch our logic, so a meta-language is needed [Tarski] |
19189 | The metalanguage must contain the object language, logic, and defined semantics [Tarski] |
10824 | If listing equivalences is a reduction of truth, witchcraft is just a list of witch-victim pairs [Field,H on Tarski] |
19190 | We need an undefined term 'true' in the meta-language, specified by axioms [Tarski] |
19197 | Truth can't be eliminated from universal claims, or from particular unspecified claims [Tarski] |
19185 | Semantics is a very modest discipline which solves no real problems [Tarski] |
19195 | Truth tables give prior conditions for logic, but are outside the system, and not definitions [Tarski] |
6110 | Subject-predicate logic (and substance-attribute metaphysics) arise from Aryan languages [Russell] |
6107 | It is logic, not metaphysics, that is fundamental to philosophy [Russell] |
19192 | The truth definition proves semantic contradiction and excluded middle laws (not the logic laws) [Tarski] |
6115 | Vagueness, and simples being beyond experience, are obstacles to a logical language [Russell] |
6109 | Some axioms may only become accepted when they lead to obvious conclusions [Russell] |
19187 | The Liar makes us assert a false sentence, so it must be taken seriously [Tarski] |
6108 | Maths can be deduced from logical axioms and the logic of relations [Russell] |
10968 | Russell gave up logical atomism because of negative, general and belief propositions [Russell, by Read] |
6113 | To mean facts we assert them; to mean simples we name them [Russell] |
6114 | 'Simples' are not experienced, but are inferred at the limits of analysis [Russell] |
21722 | Better to construct from what is known, than to infer what is unknown [Russell] |
6111 | As propositions can be put in subject-predicate form, we wrongly infer that facts have substance-quality form [Russell] |
6595 | If we need a criterion of truth, we need to know whether it is the correct criterion [Pyrrho, by Fogelin] |
6593 | The Pyrrhonians attacked the dogmas of professors, not ordinary people [Pyrrho, by Fogelin] |
6592 | Academics said that Pyrrhonians were guilty of 'negative dogmatism' [Pyrrho, by Fogelin] |
1805 | Judgements vary according to local culture and law (Mode 5) [Pyrrho, by Diog. Laertius] |
1803 | Objects vary according to which sense perceives them (Mode 3) [Pyrrho, by Diog. Laertius] |
1807 | Perception varies with viewing distance and angle (Mode 7) [Pyrrho, by Diog. Laertius] |
1810 | Perception and judgement depend on comparison (Mode 10) [Pyrrho, by Diog. Laertius] |
1802 | Individuals vary in responses and feelings (Mode 2) [Pyrrho, by Diog. Laertius] |
1801 | Animals vary in their feelings and judgements (Mode 1) [Pyrrho, by Diog. Laertius] |
1804 | Perception varies with madness or disease (Mode 4) [Pyrrho, by Diog. Laertius] |
1808 | Perception of things depends on their size or quantity (Mode 8) [Pyrrho, by Diog. Laertius] |
1806 | Perception of objects depends on surrounding conditions (Mode 6) [Pyrrho, by Diog. Laertius] |
1809 | Perception is affected by expectations (Mode 9) [Pyrrho, by Diog. Laertius] |
6112 | Meaning takes many different forms, depending on different logical types [Russell] |
3062 | There are no causes, because they are relative, and alike things can't cause one another [Pyrrho, by Diog. Laertius] |
3063 | Motion can't move where it is, and can't move where it isn't, so it can't exist [Pyrrho, by Diog. Laertius] |