95 ideas
501 | Reason is a more powerful persuader than gold [Democritus (attr)] |
10987 | Three traditional names of rules are 'Simplification', 'Addition' and 'Disjunctive Syllogism' [Read] |
11004 | Necessity is provability in S4, and true in all worlds in S5 [Read] |
11018 | There are fuzzy predicates (and sets), and fuzzy quantifiers and modifiers [Read] |
11011 | Same say there are positive, negative and neuter free logics [Read] |
11020 | Realisms like the full Comprehension Principle, that all good concepts determine sets [Read] |
14187 | If logic is topic-neutral that means it delves into all subjects, rather than having a pure subject matter [Read] |
10986 | Not all validity is captured in first-order logic [Read] |
10972 | The non-emptiness of the domain is characteristic of classical logic [Read] |
11024 | Semantics must precede proof in higher-order logics, since they are incomplete [Read] |
10985 | We should exclude second-order logic, precisely because it captures arithmetic [Read] |
14188 | Not all arguments are valid because of form; validity is just true premises and false conclusion being impossible [Read] |
14182 | If the logic of 'taller of' rests just on meaning, then logic may be the study of merely formal consequence [Read] |
14183 | Maybe arguments are only valid when suppressed premises are all stated - but why? [Read] |
10970 | A theory of logical consequence is a conceptual analysis, and a set of validity techniques [Read] |
10984 | Logical consequence isn't just a matter of form; it depends on connections like round-square [Read] |
14184 | In modus ponens the 'if-then' premise contributes nothing if the conclusion follows anyway [Read] |
14186 | Logical connectives contain no information, but just record combination relations between facts [Read] |
10973 | A theory is logically closed, which means infinite premisses [Read] |
11007 | Quantifiers are second-order predicates [Read] |
10978 | In second-order logic the higher-order variables range over all the properties of the objects [Read] |
10971 | A logical truth is the conclusion of a valid inference with no premisses [Read] |
10988 | Any first-order theory of sets is inadequate [Read] |
10974 | Compactness is when any consequence of infinite propositions is the consequence of a finite subset [Read] |
10975 | Compactness does not deny that an inference can have infinitely many premisses [Read] |
10977 | Compactness blocks the proof of 'for every n, A(n)' (as the proof would be infinite) [Read] |
10976 | Compactness makes consequence manageable, but restricts expressive power [Read] |
11014 | Self-reference paradoxes seem to arise only when falsity is involved [Read] |
11025 | Infinite cuts and successors seems to suggest an actual infinity there waiting for us [Read] |
10979 | Although second-order arithmetic is incomplete, it can fully model normal arithmetic [Read] |
10980 | Second-order arithmetic covers all properties, ensuring categoricity [Read] |
10997 | Von Neumann numbers are helpful, but don't correctly describe numbers [Read] |
11016 | Would a language without vagueness be usable at all? [Read] |
11019 | Supervaluations say there is a cut-off somewhere, but at no particular place [Read] |
11012 | A 'supervaluation' gives a proposition consistent truth-value for classical assignments [Read] |
11013 | Identities and the Indiscernibility of Identicals don't work with supervaluations [Read] |
10995 | A haecceity is a set of individual properties, essential to each thing [Read] |
11001 | Equating necessity with truth in every possible world is the S5 conception of necessity [Read] |
10992 | The point of conditionals is to show that one will accept modus ponens [Read] |
10989 | The standard view of conditionals is that they are truth-functional [Read] |
11017 | Some people even claim that conditionals do not express propositions [Read] |
14185 | Conditionals are just a shorthand for some proof, leaving out the details [Read] |
10983 | Knowledge of possible worlds is not causal, but is an ontology entailed by semantics [Read] |
10982 | How can modal Platonists know the truth of a modal proposition? [Read] |
10996 | Actualism is reductionist (to parts of actuality), or moderate realist (accepting real abstractions) [Read] |
10981 | A possible world is a determination of the truth-values of all propositions of a domain [Read] |
11000 | If worlds are concrete, objects can't be present in more than one, and can only have counterparts [Read] |
6346 | The main epistemological theories are foundationalist, coherence, probabilistic and reliabilist [Pollock/Cruz] |
6351 | Most people now agree that our reasoning proceeds defeasibly, rather than deductively [Pollock/Cruz] |
6374 | To believe maximum truths, believe everything; to have infallible beliefs, believe nothing [Pollock/Cruz] |
6355 | Direct realism says justification is partly a function of pure perceptual states, not of beliefs [Pollock/Cruz] |
6359 | Phenomenalism offered conclusive perceptual knowledge, but conclusive reasons no longer seem essential [Pollock/Cruz] |
6366 | Perception causes beliefs in us, without inference or justification [Pollock/Cruz] |
6362 | Sense evidence is not beliefs, because they are about objective properties, not about appearances [Pollock/Cruz] |
6371 | Bayesian epistemology is Bayes' Theorem plus the 'simple rule' (believe P if it is probable) [Pollock/Cruz] |
6373 | Internalism says if anything external varies, the justifiability of the belief does not vary [Pollock/Cruz] |
6353 | People rarely have any basic beliefs, and never enough for good foundations [Pollock/Cruz] |
6361 | Foundationalism requires self-justification, not incorrigibility [Pollock/Cruz] |
6357 | Reason cannot be an ultimate foundation, because rational justification requires prior beliefs [Pollock/Cruz] |
6363 | Foundationalism is wrong, because either all beliefs are prima facie justified, or none are [Pollock/Cruz] |
6365 | Negative coherence theories do not require reasons, so have no regress problem [Pollock/Cruz] |
6354 | Coherence theories fail, because they can't accommodate perception as the basis of knowledge [Pollock/Cruz] |
6367 | Coherence theories isolate justification from the world [Pollock/Cruz] |
6370 | Externalism comes as 'probabilism' (probability of truth) and 'reliabilism' (probability of good cognitive process) [Pollock/Cruz] |
6358 | One belief may cause another, without being the basis for the second belief [Pollock/Cruz] |
6364 | We can't start our beliefs from scratch, because we wouldn't know where to start [Pollock/Cruz] |
6352 | Enumerative induction gives a universal judgement, while statistical induction gives a proportion [Pollock/Cruz] |
6372 | Since every tautology has a probability of 1, should we believe all tautologies? [Pollock/Cruz] |
6360 | Scientific confirmation is best viewed as inference to the best explanation [Pollock/Cruz] |
10998 | The mind abstracts ways things might be, which are nonetheless real [Read] |
11005 | Negative existentials with compositionality make the whole sentence meaningless [Read] |
10966 | A proposition objectifies what a sentence says, as indicative, with secure references [Read] |
514 | Beauty is merely animal without intelligence [Democritus (attr)] |
525 | Behave well when alone, and feel shame in you own eyes [Democritus (attr)] |
502 | Good breeding in men means having a good character [Democritus (attr)] |
507 | Virtuous love consists of decorous desire for the beautiful [Democritus (attr)] |
521 | We should only choose pleasures which are concerned with the beautiful [Democritus (attr)] |
505 | Good and true are the same for everyone, but pleasures differ [Democritus (attr)] |
508 | Only accept beneficial pleasures [Democritus (attr)] |
520 | The great pleasures come from the contemplation of noble works [Democritus (attr)] |
522 | Moderation brings more pleasures, and so increases pleasure [Democritus (attr)] |
506 | Immoderate desire is the mark of a child, not an adult [Democritus (attr)] |
523 | It is as brave to master pleasure as to overcome the enemy [Democritus (attr)] |
503 | Virtue doesn't just avoid evil, but also doesn't desire it [Democritus (attr)] |
518 | A bad life is just a drawn-out death [Democritus (attr)] |
497 | Be virtuous from duty, not from fear [Democritus (attr)] |
499 | Repentance of shameful deeds is salvation [Democritus (attr)] |
524 | Virtue comes more from practice than from nature [Democritus (attr)] |
519 | One must avoid even speaking of evil deeds [Democritus (attr)] |
500 | The wrongdoer is more unfortunate than the person wronged [Democritus (attr)] |
526 | Small appetite makes poverty equal to wealth [Democritus (attr)] |
1539 | The endless desire for money is a crueller slavery than poverty [Democritus (attr)] |
511 | It is better to have one intelligent friend than many unintelligent [Democritus (attr)] |
498 | It is a great thing, when one is in adversity, to think of duty [Democritus (attr)] |
1541 | It is better to be poor in a democracy than be rich without freedom [Democritus (attr)] |