52 ideas
18486 | We might define truth as arising from the truth-maker relation [MacBride] |
18484 | Phenomenalists, behaviourists and presentists can't supply credible truth-makers [MacBride] |
18466 | If truthmaking is classical entailment, then anything whatsoever makes a necessary truth [MacBride] |
18473 | 'Maximalism' says every truth has an actual truthmaker [MacBride] |
18481 | Maximalism follows Russell, and optimalism (no negative or universal truthmakers) follows Wittgenstein [MacBride] |
18483 | The main idea of truth-making is that what a proposition is about is what matters [MacBride] |
18479 | There are different types of truthmakers for different types of negative truth [MacBride] |
18477 | There aren't enough positive states out there to support all the negative truths [MacBride] |
18482 | Optimalists say that negative and universal are true 'by default' from the positive truths [MacBride] |
18474 | Does 'this sentence has no truth-maker' have a truth-maker? Reductio suggests it can't have [MacBride] |
18485 | Even idealists could accept truthmakers, as mind-dependent [MacBride] |
18490 | Maybe 'makes true' is not an active verb, but just a formal connective like 'because'? [MacBride] |
18493 | Truthmaker talk of 'something' making sentences true, which presupposes objectual quantification [MacBride] |
15413 | With four tense operators, all complex tenses reduce to fourteen basic cases [Burgess] |
15415 | The temporal Barcan formulas fix what exists, which seems absurd [Burgess] |
15430 | Is classical logic a part of intuitionist logic, or vice versa? [Burgess] |
15431 | It is still unsettled whether standard intuitionist logic is complete [Burgess] |
15429 | Relevance logic's → is perhaps expressible by 'if A, then B, for that reason' [Burgess] |
11211 | If a sound conclusion comes from two errors that cancel out, the path of the argument must matter [Rumfitt] |
15404 | Technical people see logic as any formal system that can be studied, not a study of argument validity [Burgess] |
15405 | Classical logic neglects the non-mathematical, such as temporality or modality [Burgess] |
15427 | The Cut Rule expresses the classical idea that entailment is transitive [Burgess] |
15421 | Classical logic neglects counterfactuals, temporality and modality, because maths doesn't use them [Burgess] |
15403 | Philosophical logic is a branch of logic, and is now centred in computer science [Burgess] |
18489 | Connectives link sentences without linking their meanings [MacBride] |
11210 | Standardly 'and' and 'but' are held to have the same sense by having the same truth table [Rumfitt] |
15407 | Formalising arguments favours lots of connectives; proving things favours having very few [Burgess] |
11212 | The sense of a connective comes from primitively obvious rules of inference [Rumfitt] |
18476 | 'A is F' may not be positive ('is dead'), and 'A is not-F' may not be negative ('is not blind') [MacBride] |
15424 | Asserting a disjunction from one disjunct seems odd, but can be sensible, and needed in maths [Burgess] |
15409 | All occurrences of variables in atomic formulas are free [Burgess] |
15414 | The denotation of a definite description is flexible, rather than rigid [Burgess] |
15406 | 'Induction' and 'recursion' on complexity prove by connecting a formula to its atomic components [Burgess] |
15425 | The sequent calculus makes it possible to have proof without transitivity of entailment [Burgess] |
15426 | We can build one expanding sequence, instead of a chain of deductions [Burgess] |
15408 | 'Tautologies' are valid formulas of classical sentential logic - or substitution instances in other logics [Burgess] |
15418 | Validity (for truth) and demonstrability (for proof) have correlates in satisfiability and consistency [Burgess] |
15412 | Models leave out meaning, and just focus on truth values [Burgess] |
15411 | We only need to study mathematical models, since all other models are isomorphic to these [Burgess] |
15416 | We aim to get the technical notion of truth in all models matching intuitive truth in all instances [Burgess] |
15428 | The Liar seems like a truth-value 'gap', but dialethists see it as a 'glut' [Burgess] |
18480 | Maybe it only exists if it is a truthmaker (rather than the value of a variable)? [MacBride] |
18471 | Different types of 'grounding' seem to have no more than a family resemblance relation [MacBride] |
18472 | Which has priority - 'grounding' or 'truth-making'? [MacBride] |
18475 | Russell allows some complex facts, but Wittgenstein only allows atomic facts [MacBride] |
15420 | De re modality seems to apply to objects a concept intended for sentences [Burgess] |
15419 | General consensus is S5 for logical modality of validity, and S4 for proof [Burgess] |
15417 | Logical necessity has two sides - validity and demonstrability - which coincide in classical logic [Burgess] |
18478 | Wittgenstein's plan to show there is only logical necessity failed, because of colours [MacBride] |
15422 | Three conditionals theories: Materialism (material conditional), Idealism (true=assertable), Nihilism (no truth) [Burgess] |
15423 | It is doubtful whether the negation of a conditional has any clear meaning [Burgess] |
11214 | We learn 'not' along with affirmation, by learning to either affirm or deny a sentence [Rumfitt] |