37 ideas
8092 | Logic was merely a branch of rhetoric until the scientific 17th century [Devlin] |
3750 | "It is true that x" means no more than x [Ramsey] |
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] |
13430 | Infinity: there is an infinity of distinguishable individuals [Ramsey] |
13428 | Reducibility: to every non-elementary function there is an equivalent elementary function [Ramsey] |
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] |
13427 | Either 'a = b' vacuously names the same thing, or absurdly names different things [Ramsey] |
8072 | Sentences of apparent identical form can have different contextual meanings [Devlin] |
13334 | Contradictions are either purely logical or mathematical, or they involved thought and language [Ramsey] |
8075 | Space and time are atomic in the arrow, and divisible in the tortoise [Devlin] |
6409 | The 'simple theory of types' distinguishes levels among properties [Ramsey, by Grayling] |
13426 | Formalists neglect content, but the logicists have focused on generalizations, and neglected form [Ramsey] |
13425 | Formalism is hopeless, because it focuses on propositions and ignores concepts [Ramsey] |
8495 | The distinction between particulars and universals is a mistake made because of language [Ramsey] |
8493 | We could make universals collections of particulars, or particulars collections of their qualities [Ramsey] |
8494 | Obviously 'Socrates is wise' and 'Socrates has wisdom' express the same fact [Ramsey] |
13766 | 'If' is the same as 'given that', so the degrees of belief should conform to probability theory [Ramsey, by Ramsey] |
10993 | Ramsey's Test: believe the consequent if you believe the antecedent [Ramsey, by Read] |
14279 | Asking 'If p, will q?' when p is uncertain, then first add p hypothetically to your knowledge [Ramsey] |
3212 | Beliefs are maps by which we steer [Ramsey] |
22328 | I just confront the evidence, and let it act on me [Ramsey] |
22325 | A belief is knowledge if it is true, certain and obtained by a reliable process [Ramsey] |
19724 | Belief is knowledge if it is true, certain, and obtained by a reliable process [Ramsey] |
8088 | People still say the Hopi have no time concepts, despite Whorf's later denial [Devlin] |
6894 | Mental terms can be replaced in a sentence by a variable and an existential quantifier [Ramsey] |
19143 | Ramsey gave axioms for an uncertain agent to decide their preferences [Ramsey, by Davidson] |
18818 | Sentence meaning is given by the actions to which it would lead [Ramsey] |
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] |
9418 | All knowledge needs systematizing, and the axioms would be the laws of nature [Ramsey] |
9420 | Causal laws result from the simplest axioms of a complete deductive system [Ramsey] |
1513 | The Egyptians were the first to say the soul is immortal and reincarnated [Herodotus] |