50 ideas
13252 | Some truths have true negations [Beall/Restall] |
13247 | A truthmaker is an object which entails a sentence [Beall/Restall] |
13249 | (∀x)(A v B) |- (∀x)A v (∃x)B) is valid in classical logic but invalid intuitionistically [Beall/Restall] |
13243 | Excluded middle must be true for some situation, not for all situations [Beall/Restall] |
13242 | It's 'relevantly' valid if all those situations make it true [Beall/Restall] |
13245 | Relevant consequence says invalidity is the conclusion not being 'in' the premises [Beall/Restall] |
13246 | Relevant logic does not abandon classical logic [Beall/Restall] |
13254 | A doesn't imply A - that would be circular [Beall/Restall] |
13255 | Relevant logic may reject transitivity [Beall/Restall] |
13250 | Free logic terms aren't existential; classical is non-empty, with referring names [Beall/Restall] |
15845 | It seems absurd that seeing a person's limbs, the one is many, and yet the many are one [Plato] |
13235 | Logic studies consequence; logical truths are consequences of everything, or nothing [Beall/Restall] |
13238 | Syllogisms are only logic when they use variables, and not concrete terms [Beall/Restall] |
13234 | The view of logic as knowing a body of truths looks out-of-date [Beall/Restall] |
13232 | Logic studies arguments, not formal languages; this involves interpretations [Beall/Restall] |
13241 | The model theory of classical predicate logic is mathematics [Beall/Restall] |
13253 | There are several different consequence relations [Beall/Restall] |
13240 | A sentence follows from others if they always model it [Beall/Restall] |
13236 | Logical truth is much more important if mathematics rests on it, as logicism claims [Beall/Restall] |
13237 | Preface Paradox affirms and denies the conjunction of propositions in the book [Beall/Restall] |
9867 | It is absurd to define a circle, but not be able to recognise a real one [Plato] |
9865 | Daily arithmetic counts unequal things, but pure arithmetic equalises them [Plato] |
14503 | If a mixture does not contain measure and proportion, it is corrupted and destroyed [Plato] |
15857 | Any mixture which lacks measure and proportion doesn't even count as a mixture at all [Plato] |
4447 | If the good is one, is it unchanged when it is in particulars, and is it then separated from itself? [Plato] |
15856 | A thing can become one or many, depending on how we talk about it [Plato] |
374 | If one object is divided into its parts, someone can then say that one are many and many is one [Plato] |
13244 | Relevant necessity is always true for some situation (not all situations) [Beall/Restall] |
389 | How can you be certain about aspects of the world if they aren't constant? [Plato] |
13239 | Judgement is always predicating a property of a subject [Beall/Restall] |
13965 | Semantics as theory of meaning and semantics as truth-based logical consequence are very different [Soames] |
13964 | Semantic content is a proposition made of sentence constituents (not some set of circumstances) [Soames] |
13248 | We can rest truth-conditions on situations, rather than on possible worlds [Beall/Restall] |
13233 | Propositions commit to content, and not to any way of spelling it out [Beall/Restall] |
390 | If goodness involves moderation and proportion, then it seems to be found in beauty [Plato] |
392 | Neither intellect nor pleasure are the good, because they are not perfect and self-sufficient [Plato] |
391 | The good involves beauty, proportion and truth [Plato] |
393 | Good first, then beauty, then reason, then knowledge, then pleasure [Plato, by PG] |
385 | Some of the pleasures and pains we feel are false [Plato] |
387 | A small pure pleasure is much finer than a large one contaminated with pain [Plato] |
379 | The good must be sufficient and perfect, and neither intellect nor pleasure are that [Plato] |
376 | Would you prefer a life of pleasure without reason, or one of reason without pleasure? [Plato] |
371 | Reason, memory, truth and wisdom are far better than pleasure, for those who can attain them [Plato] |
373 | Pleasure is certainly very pleasant, but it doesn't follow that all pleasures are good [Plato] |
382 | It is unlikely that the gods feel either pleasure or pain [Plato] |
381 | We feel pleasure when we approach our natural state of harmony [Plato] |
386 | Intense pleasure and pain are not felt in a good body, but in a worthless one [Plato] |
388 | Hedonists must say that someone in pain is bad, even if they are virtuous [Plato] |
377 | If you lived a life of maximum pleasure, would you still be lacking anything? [Plato] |
378 | A life of pure pleasure with no intellect is the life of a jellyfish [Plato] |