47 ideas
15842 | An ad hominem refutation is reasonable, if it uses the opponent's assumptions [Harte,V] |
13252 | Some truths have true negations [Beall/Restall] |
13247 | A truthmaker is an object which entails a sentence [Beall/Restall] |
1564 | True and false statements can use exactly the same words [Anon (Diss)] |
10688 | 'Equivocation' is when terms do not mean the same thing in premises and conclusion [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] |
13246 | Relevant logic does not abandon classical logic [Beall/Restall] |
13245 | Relevant consequence says invalidity is the conclusion not being 'in' the premises [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] |
15841 | Mereology began as a nominalist revolt against the commitments of set theory [Harte,V] |
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13234 | The view of logic as knowing a body of truths looks out-of-date [Beall/Restall] |
10690 | Formal logic is invariant under permutations, or devoid of content, or gives the norms for thought [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] |
10691 | Logical consequence needs either proofs, or absence of counterexamples [Beall/Restall] |
13253 | There are several different consequence relations [Beall/Restall] |
13240 | A sentence follows from others if they always model it [Beall/Restall] |
10695 | Logical consequence is either necessary truth preservation, or preservation based on interpretation [Beall/Restall] |
10689 | A step is a 'material consequence' if we need contents as well as form [Beall/Restall] |
10696 | A 'logical truth' (or 'tautology', or 'theorem') follows from empty premises [Beall/Restall] |
13236 | Logical truth is much more important if mathematics rests on it, as logicism claims [Beall/Restall] |
10693 | Models are mathematical structures which interpret the non-logical primitives [Beall/Restall] |
13237 | Preface Paradox affirms and denies the conjunction of propositions in the book [Beall/Restall] |
10692 | Hilbert proofs have simple rules and complex axioms, and natural deduction is the opposite [Beall/Restall] |
15858 | Traditionally, the four elements are just what persists through change [Harte,V] |
15848 | Mereology treats constitution as a criterion of identity, as shown in the axiom of extensionality [Harte,V] |
15837 | What exactly is a 'sum', and what exactly is 'composition'? [Harte,V] |
15839 | If something is 'more than' the sum of its parts, is the extra thing another part, or not? [Harte,V] |
15838 | The problem with the term 'sum' is that it is singular [Harte,V] |
13244 | Relevant necessity is always true for some situation (not all situations) [Beall/Restall] |
1561 | Anything can be acceptable in some circumstances and unacceptable in others [Anon (Diss)] |
1560 | Lydians prostitute their daughters to raise a dowery, but no Greek would marry such a girl [Anon (Diss)] |
1559 | Thracians think tattooing adds to a girl's beauty, but elsewhere it is a punishment [Anon (Diss)] |
13239 | Judgement is always predicating a property of a subject [Beall/Restall] |
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] |
1567 | How could someone who knows everything fail to act correctly? [Anon (Diss)] |
1563 | Every apparent crime can be right in certain circumstances [Anon (Diss), by PG] |
1562 | It is right to lie to someone, to get them to take medicine they are reluctant to take [Anon (Diss)] |
1566 | The first priority in elections is to vote for people who support democracy [Anon (Diss)] |
1565 | We learn language, and we don't know who teaches us it [Anon (Diss)] |