33 ideas
17596 | Coherence problems have positive and negative restraints; solutions maximise constraint satisfaction [Thagard] |
17597 | Coherence is explanatory, deductive, conceptual, analogical, perceptual, and deliberative [Thagard] |
17598 | Explanatory coherence needs symmetry,explanation,analogy,data priority, contradiction,competition,acceptance [Thagard] |
17602 | Verisimilitude comes from including more phenomena, and revealing what underlies [Thagard] |
13520 | A 'tautology' must include connectives [Wolf,RS] |
13524 | Deduction Theorem: T∪{P}|-Q, then T|-(P→Q), which justifies Conditional Proof [Wolf,RS] |
13521 | Universal Specification: ∀xP(x) implies P(t). True for all? Then true for an instance [Wolf,RS] |
13522 | Universal Generalization: If we prove P(x) with no special assumptions, we can conclude ∀xP(x) [Wolf,RS] |
13523 | Existential Generalization (or 'proof by example'): if we can say P(t), then we can say something is P [Wolf,RS] |
13529 | Empty Set: ∃x∀y ¬(y∈x). The unique empty set exists [Wolf,RS] |
13526 | Comprehension Axiom: if a collection is clearly specified, it is a set [Wolf,RS] |
13534 | In first-order logic syntactic and semantic consequence (|- and |=) nicely coincide [Wolf,RS] |
13535 | First-order logic is weakly complete (valid sentences are provable); we can't prove every sentence or its negation [Wolf,RS] |
13519 | Model theory uses sets to show that mathematical deduction fits mathematical truth [Wolf,RS] |
13531 | Model theory reveals the structures of mathematics [Wolf,RS] |
13532 | Model theory 'structures' have a 'universe', some 'relations', some 'functions', and some 'constants' [Wolf,RS] |
13533 | First-order model theory rests on completeness, compactness, and the Löwenheim-Skolem-Tarski theorem [Wolf,RS] |
13537 | An 'isomorphism' is a bijection that preserves all structural components [Wolf,RS] |
13539 | The LST Theorem is a serious limitation of first-order logic [Wolf,RS] |
13538 | If a theory is complete, only a more powerful language can strengthen it [Wolf,RS] |
13525 | Most deductive logic (unlike ordinary reasoning) is 'monotonic' - we don't retract after new givens [Wolf,RS] |
13530 | An ordinal is an equivalence class of well-orderings, or a transitive set whose members are transitive [Wolf,RS] |
13518 | Modern mathematics has unified all of its objects within set theory [Wolf,RS] |
17601 | Neither a priori rationalism nor sense data empiricism account for scientific knowledge [Thagard] |
17600 | Bayesian inference is forced to rely on approximations [Thagard] |
17066 | 3: If an analogous pair explain another analogous pair, then they all cohere [Thagard, by Smart] |
17064 | 1: Coherence is a symmetrical relation between two propositions [Thagard, by Smart] |
17067 | 4: For coherence, observation reports have a degree of intrinsic acceptability [Thagard, by Smart] |
17068 | 5: Contradictory propositions incohere [Thagard, by Smart] |
17069 | 6: A proposition's acceptability depends on its coherence with a system [Thagard, by Smart] |
17065 | 2: An explanation must wholly cohere internally, and with the new fact [Thagard, by Smart] |
17599 | The best theory has the highest subjective (Bayesian) probability? [Thagard] |
9287 | Bruno said that ancient Egyptian magic was the true religion [Bruno, by Yates] |