95 ideas
16325 | Analysis rests on natural language, but its ideal is a framework which revises language [Halbach] |
17663 | If you know what it is, investigation is pointless. If you don't, investigation is impossible [Armstrong] |
22024 | Fichte's subjectivity struggles to then give any account of objectivity [Pinkard on Fichte] |
16292 | An explicit definition enables the elimination of what is defined [Halbach] |
16307 | Don't trust analogies; they are no more than a guideline [Halbach] |
16339 | Truth axioms prove objects exist, so truth doesn't seem to be a logical notion [Halbach] |
16330 | Truth-value 'gluts' allow two truth values together; 'gaps' give a partial conception of truth [Halbach] |
16293 | Traditional definitions of truth often make it more obscure, rather than less [Halbach] |
16324 | Any definition of truth requires a metalanguage [Halbach] |
16301 | If people have big doubts about truth, a definition might give it more credibility [Halbach] |
16297 | Semantic theories avoid Tarski's Theorem by sticking to a sublanguage [Halbach] |
16337 | Disquotational truth theories are short of deductive power [Halbach] |
16294 | Axiomatic truth doesn't presuppose a truth-definition, though it could admit it at a later stage [Halbach] |
16326 | The main semantic theories of truth are Kripke's theory, and revisions semantics [Halbach] |
16299 | Gödel numbering means a theory of truth can use Peano Arithmetic as its base theory [Halbach] |
16340 | Truth axioms need a base theory, because that is where truth issues arise [Halbach] |
16305 | We know a complete axiomatisation of truth is not feasible [Halbach] |
16311 | To axiomatise Tarski's truth definition, we need a binary predicate for his 'satisfaction' [Halbach] |
16318 | Compositional Truth CT has the truth of a sentence depending of the semantic values of its constituents [Halbach] |
16322 | CT proves PA consistent, which PA can't do on its own, so CT is not conservative over PA [Halbach] |
16313 | A theory is 'conservative' if it adds no new theorems to its base theory [Halbach, by PG] |
16315 | The Tarski Biconditional theory TB is Peano Arithmetic, plus truth, plus all Tarski bi-conditionals [Halbach] |
16314 | Theories of truth are 'typed' (truth can't apply to sentences containing 'true'), or 'type-free' [Halbach] |
16327 | Friedman-Sheard is type-free Compositional Truth, with two inference rules for truth [Halbach] |
16329 | Kripke-Feferman theory KF axiomatises Kripke fixed-points, with Strong Kleene logic with gluts [Halbach] |
16331 | The KF is much stronger deductively that FS, which relies on classical truth [Halbach] |
16332 | The KF theory is useful, but it is not a theory containing its own truth predicate [Halbach] |
16317 | The main problem for deflationists is they can express generalisations, but not prove them [Halbach] |
16320 | Some say deflationism is axioms which are conservative over the base theory [Halbach] |
16338 | Deflationism says truth is a disquotation device to express generalisations, adding no new knowledge [Halbach] |
16316 | Deflationists say truth is just for expressing infinite conjunctions or generalisations [Halbach] |
16319 | Compositional Truth CT proves generalisations, so is preferred in discussions of deflationism [Halbach] |
16335 | In Strong Kleene logic a disjunction just needs one disjunct to be true [Halbach] |
16334 | In Weak Kleene logic there are 'gaps', neither true nor false if one component lacks a truth value [Halbach] |
16309 | Every attempt at formal rigour uses some set theory [Halbach] |
16333 | The underestimated costs of giving up classical logic are found in mathematical reasoning [Halbach] |
22017 | Normativity needs the possibility of negation, in affirmation and denial [Fichte, by Pinkard] |
16310 | A theory is some formulae and all of their consequences [Halbach] |
16341 | Normally we only endorse a theory if we believe it to be sound [Halbach] |
16344 | Soundness must involve truth; the soundness of PA certainly needs it [Halbach] |
16342 | You cannot just say all of Peano arithmetic is true, as 'true' isn't part of the system [Halbach] |
16347 | Many new paradoxes may await us when we study interactions between frameworks [Halbach] |
16336 | The liar paradox applies truth to a negated truth (but the conditional will serve equally) [Halbach] |
16321 | The compactness theorem can prove nonstandard models of PA [Halbach] |
16343 | The global reflection principle seems to express the soundness of Peano Arithmetic [Halbach] |
16312 | To reduce PA to ZF, we represent the non-negative integers with von Neumann ordinals [Halbach] |
16308 | Set theory was liberated early from types, and recently truth-theories are exploring type-free [Halbach] |
16345 | That Peano arithmetic is interpretable in ZF set theory is taken by philosophers as a reduction [Halbach] |
17688 | Negative facts are supervenient on positive facts, suggesting they are positive facts [Armstrong] |
17691 | Nothing is genuinely related to itself [Armstrong] |
17679 | All instances of some property are strictly identical [Armstrong] |
12677 | Armstrong holds that all basic properties are categorical [Armstrong, by Ellis] |
17667 | Dispositions exist, but their truth-makers are actual or categorical properties [Armstrong] |
17687 | If everything is powers there is a vicious regress, as powers are defined by more powers [Armstrong] |
17666 | Actualism means that ontology cannot contain what is merely physically possible [Armstrong] |
17678 | Universals are just the repeatable features of a world [Armstrong] |
17669 | Realist regularity theories of laws need universals, to pick out the same phenomena [Armstrong] |
17677 | Past, present and future must be equally real if universals are instantiated [Armstrong] |
17686 | Universals are abstractions from states of affairs [Armstrong] |
15442 | Universals are abstractions from their particular instances [Armstrong, by Lewis] |
17668 | It is likely that particulars can be individuated by unique conjunctions of properties [Armstrong] |
17680 | The identity of a thing with itself can be ruled out as a pseudo-property [Armstrong] |
16346 | Maybe necessity is a predicate, not the usual operator, to make it more like truth [Halbach] |
17693 | The necessary/contingent distinction may need to recognise possibilities as real [Armstrong] |
22018 | Necessary truths from basic assertion and negation [Fichte, by Pinkard] |
22064 | Fichte's logic is much too narrow, and doesn't deduce ethics, art, society or life [Schlegel,F on Fichte] |
22032 | Fichte's key claim was that the subjective-objective distinction must itself be subjective [Fichte, by Pinkard] |
17685 | Induction aims at 'all Fs', but abduction aims at hidden or theoretical entities [Armstrong] |
17683 | Science suggests that the predicate 'grue' is not a genuine single universal [Armstrong] |
17675 | Unlike 'green', the 'grue' predicate involves a time and a change [Armstrong] |
17674 | The raven paradox has three disjuncts, confirmed by confirming any one of them [Armstrong] |
17672 | A good reason for something (the smoke) is not an explanation of it (the fire) [Armstrong] |
17684 | To explain observations by a regular law is to explain the observations by the observations [Armstrong] |
17676 | Best explanations explain the most by means of the least [Armstrong] |
22020 | We only see ourselves as self-conscious and rational in relation to other rationalities [Fichte] |
22060 | The Self is the spontaneity, self-relatedness and unity needed for knowledge [Fichte, by Siep] |
22066 | Novalis sought a much wider concept of the ego than Fichte's proposal [Novalis on Fichte] |
22016 | The self is not a 'thing', but what emerges from an assertion of normativity [Fichte, by Pinkard] |
22019 | Consciousness of an object always entails awareness of the self [Fichte] |
22061 | Judgement is distinguishing concepts, and seeing their relations [Fichte, by Siep] |
17664 | Each subject has an appropriate level of abstraction [Armstrong] |
16298 | We need propositions to ascribe the same beliefs to people with different languages [Halbach] |
22023 | Fichte's idea of spontaneity implied that nothing counts unless we give it status [Fichte, by Pinkard] |
22065 | Fichte reduces nature to a lifeless immobility [Schlegel,F on Fichte] |
17692 | We can't deduce the phenomena from the One [Armstrong] |
17689 | Absences might be effects, but surely not causes? [Armstrong] |
17662 | Science depends on laws of nature to study unobserved times and spaces [Armstrong] |
17682 | A universe couldn't consist of mere laws [Armstrong] |
17690 | Oaken conditional laws, Iron universal laws, and Steel necessary laws [Armstrong, by PG] |
17670 | Newton's First Law refers to bodies not acted upon by a force, but there may be no such body [Armstrong] |
8582 | Regularities are lawful if a second-order universal unites two first-order universals [Armstrong, by Lewis] |
17671 | A naive regularity view says if it never occurs then it is impossible [Armstrong] |
16246 | Rather than take necessitation between universals as primitive, just make laws primitive [Maudlin on Armstrong] |
9480 | Armstrong has an unclear notion of contingent necessitation, which can't necessitate anything [Bird on Armstrong] |
17681 | The laws of nature link properties with properties [Armstrong] |