31 ideas
14018 | Is Sufficient Reason self-refuting (no reason to accept it!), or is it a legitimate explanatory tool? [Bourne] |
14008 | The redundancy theory conflates metalinguistic bivalence with object-language excluded middle [Bourne] |
10775 | The axiom of choice now seems acceptable and obvious (if it is meaningful) [Tharp] |
10766 | Logic is either for demonstration, or for characterizing structures [Tharp] |
10767 | Elementary logic is complete, but cannot capture mathematics [Tharp] |
10769 | Second-order logic isn't provable, but will express set-theory and classic problems [Tharp] |
10762 | In sentential logic there is a simple proof that all truth functions can be reduced to 'not' and 'and' [Tharp] |
10776 | The main quantifiers extend 'and' and 'or' to infinite domains [Tharp] |
10774 | There are at least five unorthodox quantifiers that could be used [Tharp] |
10777 | Skolem mistakenly inferred that Cantor's conceptions were illusory [Tharp] |
10773 | The Löwenheim-Skolem property is a limitation (e.g. can't say there are uncountably many reals) [Tharp] |
10765 | Soundness would seem to be an essential requirement of a proof procedure [Tharp] |
10763 | Completeness and compactness together give axiomatizability [Tharp] |
10770 | If completeness fails there is no algorithm to list the valid formulas [Tharp] |
10771 | Compactness is important for major theories which have infinitely many axioms [Tharp] |
10772 | Compactness blocks infinite expansion, and admits non-standard models [Tharp] |
10764 | A complete logic has an effective enumeration of the valid formulas [Tharp] |
10768 | Effective enumeration might be proved but not specified, so it won't guarantee knowledge [Tharp] |
13007 | Archimedes defined a straight line as the shortest distance between two points [Archimedes, by Leibniz] |
14010 | All relations between spatio-temporal objects are either spatio-temporal, or causal [Bourne] |
14009 | It is a necessary condition for the existence of relations that both of the relata exist [Bourne] |
14016 | The idea of simultaneity in Special Relativity is full of verificationist assumptions [Bourne] |
14019 | Relativity denies simultaneity, so it needs past, present and future (unlike Presentism) [Bourne] |
14013 | Special Relativity allows an absolute past, future, elsewhere and simultaneity [Bourne] |
14015 | No-Futurists believe in past and present, but not future, and say the world grows as facts increase [Bourne] |
14007 | How can presentists talk of 'earlier than', and distinguish past from future? [Bourne] |
14011 | Presentism seems to deny causation, because the cause and the effect can never coexist [Bourne] |
14017 | Since presentists treat the presentness of events as basic, simultaneity should be define by that means [Bourne] |
14003 | Time is tensed or tenseless; the latter says all times and objects are real, and there is no passage of time [Bourne] |
14005 | B-series objects relate to each other; A-series objects relate to the present [Bourne] |
14006 | Time flows, past is fixed, future is open, future is feared but not past, we remember past, we plan future [Bourne] |