30 ideas
8092 | Logic was merely a branch of rhetoric until the scientific 17th century [Devlin] |
4739 | In "if and only if" (iff), "if" expresses the sufficient condition, and "only if" the necessary condition [Engel] |
4737 | Are truth-bearers propositions, or ideas/beliefs, or sentences/utterances? [Engel] |
4750 | The redundancy theory gets rid of facts, for 'it is a fact that p' just means 'p' [Engel] |
4744 | We can't explain the corresponding structure of the world except by referring to our thoughts [Engel] |
4738 | The coherence theory says truth is an internal relationship between groups of truth-bearers [Engel] |
4745 | Any coherent set of beliefs can be made more coherent by adding some false beliefs [Engel] |
4753 | Deflationism seems to block philosophers' main occupation, asking metatheoretical questions [Engel] |
4755 | Deflationism cannot explain why we hold beliefs for reasons [Engel] |
4751 | Maybe there is no more to be said about 'true' than there is about the function of 'and' in logic [Engel] |
8081 | 'No councillors are bankers' and 'All bankers are athletes' implies 'Some athletes are not councillors' [Devlin] |
8085 | Modern propositional inference replaces Aristotle's 19 syllogisms with modus ponens [Devlin] |
8086 | Predicate logic retains the axioms of propositional logic [Devlin] |
8091 | Situation theory is logic that takes account of context [Devlin] |
8087 | Golden ages: 1900-1960 for pure logic, and 1950-1985 for applied logic [Devlin] |
8089 | Montague's intensional logic incorporated the notion of meaning [Devlin] |
8082 | Where a conditional is purely formal, an implication implies a link between premise and conclusion [Devlin] |
4752 | Deflationism must reduce bivalence ('p is true or false') to excluded middle ('p or not-p') [Engel] |
8072 | Sentences of apparent identical form can have different contextual meanings [Devlin] |
8075 | Space and time are atomic in the arrow, and divisible in the tortoise [Devlin] |
12887 | A whole must have one characteristic, an internal relation, and a structure [Rescher/Oppenheim] |
4762 | The Humean theory of motivation is that beliefs may be motivators as well as desires [Engel] |
4754 | Our beliefs are meant to fit the world (i.e. be true), where we want the world to fit our desires [Engel] |
4763 | 'Evidentialists' say, and 'voluntarists' deny, that we only believe on the basis of evidence [Engel] |
4746 | Pragmatism is better understood as a theory of belief than as a theory of truth [Engel] |
4764 | We cannot directly control our beliefs, but we can control the causes of our involuntary beliefs [Engel] |
8088 | People still say the Hopi have no time concepts, despite Whorf's later denial [Devlin] |
4759 | Mental states as functions are second-order properties, realised by first-order physical properties [Engel] |
8073 | How do we parse 'time flies like an arrow' and 'fruit flies like an apple'? [Devlin] |
8076 | The distinction between sentences and abstract propositions is crucial in logic [Devlin] |