79 ideas
| 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] |
| 22246 | A train of reasoning must be treated as all happening simultaneously [Recanati] |
| 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] |
| 15407 | Formalising arguments favours lots of connectives; proving things favours having very few [Burgess] |
| 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] |
| 16357 | Mental files are the counterparts of singular terms [Recanati] |
| 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] |
| 10185 | Set theory is the standard background for modern mathematics [Burgess] |
| 10184 | Structuralists take the name 'R' of the reals to be a variable ranging over structures, not a structure [Burgess] |
| 10189 | There is no one relation for the real number 2, as relations differ in different models [Burgess] |
| 10186 | If set theory is used to define 'structure', we can't define set theory structurally [Burgess] |
| 10187 | Abstract algebra concerns relations between models, not common features of all the models [Burgess] |
| 10188 | How can mathematical relations be either internal, or external, or intrinsic? [Burgess] |
| 16360 | Identity statements are informative if they link separate mental files [Recanati] |
| 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] |
| 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] |
| 16374 | There is a continuum from acquaintance to description in knowledge, depending on the link [Recanati] |
| 18409 | Indexicals apply to singular thought, and mental files have essentially indexical features [Recanati] |
| 22247 | Indexicality is not just a feature of language; examples show it also occurs in thought [Recanati] |
| 22248 | How can we communicate indexical thoughts to people not in the right context? [Recanati] |
| 16354 | Indexicality is closely related to singularity, exploiting our direct relations with things [Recanati] |
| 16371 | Files can be confused, if two files correctly have a single name, or one file has two names [Recanati] |
| 16373 | Encylopedic files have further epistemic links, beyond the basic one [Recanati] |
| 16375 | Singular thoughts need a mental file, and an acquaintance relation from file to object [Recanati] |
| 16377 | Expected acquaintance can create a thought-vehicle file, but without singular content [Recanati] |
| 16378 | An 'indexed' file marks a file which simulates the mental file of some other person [Recanati] |
| 16387 | Reference by mental files is Millian, in emphasising acquaintance, rather than satisfaction [Recanati] |
| 16358 | The reference of a file is fixed by what it relates to, not the information it contains [Recanati] |
| 16361 | A mental file treats all of its contents as concerning one object [Recanati] |
| 16367 | There are transient 'demonstrative' files, habitual 'recognitional' files, cumulative 'encyclopedic' files [Recanati] |
| 16368 | Files are hierarchical: proto-files, then first-order, then higher-order encyclopedic [Recanati] |
| 16370 | A file has a 'nucleus' through its relation to the object, and a 'periphery' of links to other files [Recanati] |
| 22242 | Mental files are concepts, which are either collections or (better) containers [Recanati] |
| 22243 | The Frege case of believing a thing is both F and not-F is explained by separate mental files [Recanati] |
| 16381 | The content of thought is what is required to understand it (which involves hearers) [Recanati] |
| 16365 | Mental files are individual concepts (thought constituents) [Recanati] |
| 16356 | There may be two types of reference in language and thought: descriptive and direct [Recanati] |
| 16393 | In super-direct reference, the referent serves as its own vehicle of reference [Recanati] |
| 16386 | Direct reference is strong Millian (just a tag) or weak Kaplanian (allowing descriptions as well) [Recanati] |
| 16372 | Sense determines reference says same sense/same reference; new reference means new sense [Recanati] |
| 16388 | We need sense as well as reference, but in a non-descriptive form, and mental files do that [Recanati] |
| 16359 | Sense is a mental file (not its contents); similar files for Cicero and Tully are two senses [Recanati] |
| 16355 | Problems with descriptivism are reference by perception, by communications and by indexicals [Recanati] |
| 16348 | Descriptivism says we mentally relate to objects through their properties [Recanati] |
| 16384 | Definite descriptions reveal either a predicate (attributive use) or the file it belongs in (referential) [Recanati] |
| 16352 | A rigid definite description can be attributive, not referential: 'the actual F, whoever he is….' [Recanati] |
| 22245 | A linguistic expression refers to what its associated mental file refers to [Recanati] |
| 16353 | Singularity cannot be described, and it needs actual world relations [Recanati] |
| 16382 | Fregean modes of presentation can be understood as mental files [Recanati] |
| 16389 | If two people think 'I am tired', they think the same thing, and they think different things [Recanati] |
| 16363 | Indexicals (like mental files) determine their reference relationally, not by satisfaction [Recanati] |
| 16364 | Indexical don't refer; only their tokens do [Recanati] |
| 16351 | In 2-D semantics, reference is determined, then singularity by the truth of a predication [Recanati] |
| 16350 | Two-D semantics is said to help descriptivism of reference deal with singular objects [Recanati] |
| 16380 | Russellian propositions are better than Fregean thoughts, by being constant through communication [Recanati] |
| 22250 | There are speakers' thoughts and hearers' thoughts, but no further thought attached to the utterance [Recanati] |
| 22249 | The Naive view of communication is that hearers acquire exactly the thoughts of the speaker [Recanati] |
| 1513 | The Egyptians were the first to say the soul is immortal and reincarnated [Herodotus] |