238 ideas
19199 | Some say metaphysics is a highly generalised empirical study of objects [Tarski] |
18390 | All metaphysical discussion should be guided by a quest for truthmakers [Armstrong] |
19193 | Disputes that fail to use precise scientific terminology are all meaningless [Tarski] |
17663 | If you know what it is, investigation is pointless. If you don't, investigation is impossible [Armstrong] |
4036 | What matters is not how many entities we postulate, but how many kinds of entities [Armstrong, by Mellor/Oliver] |
19179 | For a definition we need the words or concepts used, the rules, and the structure of the language [Tarski] |
16295 | Tarski proved that truth cannot be defined from within a given theory [Tarski, by Halbach] |
15342 | Tarski proved that any reasonably expressive language suffers from the liar paradox [Tarski, by Horsten] |
19069 | 'True sentence' has no use consistent with logic and ordinary language, so definition seems hopeless [Tarski] |
10153 | In everyday language, truth seems indefinable, inconsistent, and illogical [Tarski] |
19178 | Definitions of truth should not introduce a new version of the concept, but capture the old one [Tarski] |
19177 | A definition of truth should be materially adequate and formally correct [Tarski] |
19186 | A rigorous definition of truth is only possible in an exactly specified language [Tarski] |
19194 | We may eventually need to split the word 'true' into several less ambiguous terms [Tarski] |
18467 | Truth-making can't be entailment, because truthmakers are portions of reality [Armstrong] |
18468 | Armstrong says truthmakers necessitate their truth, where 'necessitate' is a primitive relation [Armstrong, by MacBride] |
15547 | Negative existentials have 'totality facts' as truthmakers [Armstrong, by Lewis] |
18377 | Negative truths have as truthmakers all states of affairs relevant to the truth [Armstrong] |
18382 | The nature of arctic animals is truthmaker for the absence of penguins there [Armstrong] |
18394 | In mathematics, truthmakers are possible instantiations of structures [Armstrong] |
18384 | One truthmaker will do for a contingent truth and for its contradictory [Armstrong] |
18387 | The truthmakers for possible unicorns are the elements in their combination [Armstrong] |
18386 | What is the truthmaker for 'it is possible that there could have been nothing'? [Armstrong] |
18381 | Necessitating general truthmakers must also specify their limits [Armstrong] |
4742 | Correspondence may be one-many or many one, as when either p or q make 'p or q' true [Armstrong] |
16296 | Tarski's Theorem renders any precise version of correspondence impossible [Tarski, by Halbach] |
10672 | Tarskian semantics says that a sentence is true iff it is satisfied by every sequence [Tarski, by Hossack] |
13338 | '"It is snowing" is true if and only if it is snowing' is a partial definition of the concept of truth [Tarski] |
4699 | Tarski made truth relative, by only defining truth within some given artificial language [Tarski, by O'Grady] |
19324 | Tarski has to avoid stating how truths relate to states of affairs [Kirkham on Tarski] |
15339 | Tarski gave up on the essence of truth, and asked how truth is used, or how it functions [Tarski, by Horsten] |
16302 | Tarski did not just aim at a definition; he also offered an adequacy criterion for any truth definition [Tarski, by Halbach] |
19135 | Tarski enumerates cases of truth, so it can't be applied to new words or languages [Davidson on Tarski] |
19138 | Tarski define truths by giving the extension of the predicate, rather than the meaning [Davidson on Tarski] |
19180 | It is convenient to attach 'true' to sentences, and hence the language must be specified [Tarski] |
19181 | In the classical concept of truth, 'snow is white' is true if snow is white [Tarski] |
19196 | Scheme (T) is not a definition of truth [Tarski] |
19183 | Each interpreted T-sentence is a partial definition of truth; the whole definition is their conjunction [Tarski] |
19182 | Use 'true' so that all T-sentences can be asserted, and the definition will then be 'adequate' [Tarski] |
19198 | We don't give conditions for asserting 'snow is white'; just that assertion implies 'snow is white' is true [Tarski] |
15410 | Truth only applies to closed formulas, but we need satisfaction of open formulas to define it [Burgess on Tarski] |
18811 | Tarski uses sentential functions; truly assigning the objects to variables is what satisfies them [Tarski, by Rumfitt] |
15365 | We can define the truth predicate using 'true of' (satisfaction) for variables and some objects [Tarski, by Horsten] |
19314 | For physicalism, reduce truth to satisfaction, then define satisfaction as physical-plus-logic [Tarski, by Kirkham] |
19316 | Insight: don't use truth, use a property which can be compositional in complex quantified sentence [Tarski, by Kirkham] |
19175 | Tarski gave axioms for satisfaction, then derived its explicit definition, which led to defining truth [Tarski, by Davidson] |
19184 | The best truth definition involves other semantic notions, like satisfaction (relating terms and objects) [Tarski] |
19191 | Specify satisfaction for simple sentences, then compounds; true sentences are satisfied by all objects [Tarski] |
19188 | We can't use a semantically closed language, or ditch our logic, so a meta-language is needed [Tarski] |
19189 | The metalanguage must contain the object language, logic, and defined semantics [Tarski] |
19134 | Tarski defined truth for particular languages, but didn't define it across languages [Davidson on Tarski] |
16304 | Tarski didn't capture the notion of an adequate truth definition, as Convention T won't prove non-contradiction [Halbach on Tarski] |
2571 | Tarski says that his semantic theory of truth is completely neutral about all metaphysics [Tarski, by Haack] |
10821 | Physicalists should explain reference nonsemantically, rather than getting rid of it [Tarski, by Field,H] |
10822 | A physicalist account must add primitive reference to Tarski's theory [Field,H on Tarski] |
10824 | If listing equivalences is a reduction of truth, witchcraft is just a list of witch-victim pairs [Field,H on Tarski] |
16303 | Tarski made truth respectable, by proving that it could be defined [Tarski, by Halbach] |
10969 | Tarski had a theory of truth, and a theory of theories of truth [Tarski, by Read] |
17746 | Tarski's 'truth' is a precise relation between the language and its semantics [Tarski, by Walicki] |
10904 | Tarskian truth neglects the atomic sentences [Mulligan/Simons/Smith on Tarski] |
15322 | Tarski's had the first axiomatic theory of truth that was minimally adequate [Tarski, by Horsten] |
16306 | Tarski defined truth, but an axiomatisation can be extracted from his inductive clauses [Tarski, by Halbach] |
19141 | Tarski thought axiomatic truth was too contingent, and in danger of inconsistencies [Tarski, by Davidson] |
19190 | We need an undefined term 'true' in the meta-language, specified by axioms [Tarski] |
19197 | Truth can't be eliminated from universal claims, or from particular unspecified claims [Tarski] |
19185 | Semantics is a very modest discipline which solves no real problems [Tarski] |
9542 | The best known axiomatization of PL is Whitehead/Russell, with four axioms and two rules [Russell/Whitehead, by Hughes/Cresswell] |
19195 | Truth tables give prior conditions for logic, but are outside the system, and not definitions [Tarski] |
15544 | If what is actual might have been impossible, we need S4 modal logic [Armstrong, by Lewis] |
18396 | The set theory brackets { } assert that the member is a unit [Armstrong] |
18393 | For 'there is a class with no members' we don't need the null set as truthmaker [Armstrong] |
21720 | Russell saw Reducibility as legitimate for reducing classes to logic [Linsky,B on Russell/Whitehead] |
10044 | Russell denies extensional sets, because the null can't be a collection, and the singleton is just its element [Russell/Whitehead, by Shapiro] |
18208 | We regard classes as mere symbolic or linguistic conveniences [Russell/Whitehead] |
10152 | Set theory and logic are fairy tales, but still worth studying [Tarski] |
10048 | There is no clear boundary between the logical and the non-logical [Tarski] |
13337 | A language: primitive terms, then definition rules, then sentences, then axioms, and finally inference rules [Tarski] |
18812 | Split out the logical vocabulary, make an assignment to the rest. It's logical if premises and conclusion match [Tarski, by Rumfitt] |
10694 | Logical consequence is when in any model in which the premises are true, the conclusion is true [Tarski, by Beall/Restall] |
10479 | Logical consequence: true premises give true conclusions under all interpretations [Tarski, by Hodges,W] |
13344 | X follows from sentences K iff every model of K also models X [Tarski] |
8204 | Lewis's 'strict implication' preserved Russell's confusion of 'if...then' with implication [Quine on Russell/Whitehead] |
9359 | Russell's implication means that random sentences imply one another [Lewis,CI on Russell/Whitehead] |
21707 | Russell unusually saw logic as 'interpreted' (though very general, and neutral) [Russell/Whitehead, by Linsky,B] |
19192 | The truth definition proves semantic contradiction and excluded middle laws (not the logic laws) [Tarski] |
18759 | Identity is invariant under arbitrary permutations, so it seems to be a logical term [Tarski, by McGee] |
10036 | In 'Principia' a new abstract theory of relations appeared, and was applied [Russell/Whitehead, by Gödel] |
10823 | A name denotes an object if the object satisfies a particular sentential function [Tarski] |
18756 | Tarski built a compositional semantics for predicate logic, from dependent satisfactions [Tarski, by McGee] |
19313 | Tarksi invented the first semantics for predicate logic, using this conception of truth [Tarski, by Kirkham] |
13335 | Semantics is the concepts of connections of language to reality, such as denotation, definition and truth [Tarski] |
13336 | A language containing its own semantics is inconsistent - but we can use a second language [Tarski] |
13339 | A sentence is satisfied when we can assert the sentence when the variables are assigned [Tarski] |
13340 | Satisfaction is the easiest semantical concept to define, and the others will reduce to it [Tarski] |
16323 | The object language/ metalanguage distinction is the basis of model theory [Tarski, by Halbach] |
13343 | A 'model' is a sequence of objects which satisfies a complete set of sentential functions [Tarski] |
13341 | Using the definition of truth, we can prove theories consistent within sound logics [Tarski] |
8940 | Tarski avoids the Liar Paradox, because truth cannot be asserted within the object language [Tarski, by Fisher] |
19187 | The Liar makes us assert a false sentence, so it must be taken seriously [Tarski] |
18248 | A real number is the class of rationals less than the number [Russell/Whitehead, by Shapiro] |
18392 | Classes have cardinalities, so their members must all be treated as units [Armstrong] |
10157 | Tarski improved Hilbert's geometry axioms, and without set-theory [Tarski, by Feferman/Feferman] |
18152 | Russell takes numbers to be classes, but then reduces the classes to numerical quantifiers [Russell/Whitehead, by Bostock] |
10037 | 'Principia' lacks a precise statement of the syntax [Gödel on Russell/Whitehead] |
10025 | Russell and Whitehead took arithmetic to be higher-order logic [Russell/Whitehead, by Hodes] |
8683 | Russell and Whitehead were not realists, but embraced nearly all of maths in logic [Russell/Whitehead, by Friend] |
10093 | The ramified theory of types used propositional functions, and covered bound variables [Russell/Whitehead, by George/Velleman] |
8691 | The Russell/Whitehead type theory was limited, and was not really logic [Friend on Russell/Whitehead] |
10305 | In 'Principia Mathematica', logic is exceeded in the axioms of infinity and reducibility, and in the domains [Bernays on Russell/Whitehead] |
10154 | Tarski's theory of truth shifted the approach away from syntax, to set theory and semantics [Feferman/Feferman on Tarski] |
8684 | Russell and Whitehead consider the paradoxes to indicate that we create mathematical reality [Russell/Whitehead, by Friend] |
8746 | To avoid vicious circularity Russell produced ramified type theory, but Ramsey simplified it [Russell/Whitehead, by Shapiro] |
18385 | Logical atomism builds on the simple properties, but are they the only possible properties? [Armstrong] |
8507 | Some think of reality as made of things; I prefer facts or states of affairs [Armstrong] |
18391 | 'Naturalism' says only the world of space-time exists [Armstrong] |
9497 | Without modality, Armstrong falls back on fictionalism to support counterfactual laws [Bird on Armstrong] |
17688 | Negative facts are supervenient on positive facts, suggesting they are positive facts [Armstrong] |
18374 | Truthmaking needs states of affairs, to unite particulars with tropes or universals. [Armstrong] |
17691 | Nothing is genuinely related to itself [Armstrong] |
7024 | Properties are universals, which are always instantiated [Armstrong, by Heil] |
17679 | All instances of some property are strictly identical [Armstrong] |
15550 | Properties are contingently existing beings with multiple locations in space and time [Armstrong, by Lewis] |
15754 | Without properties we would be unable to express the laws of nature [Armstrong] |
18372 | We need properties, as minimal truthmakers for the truths about objects [Armstrong] |
18379 | The determinates of a determinable must be incompatible with each other [Armstrong] |
18378 | Length is a 'determinable' property, and one mile is one its 'determinates' [Armstrong] |
9478 | Even if all properties are categorical, they may be denoted by dispositional predicates [Armstrong, by Bird] |
12677 | Armstrong holds that all basic properties are categorical [Armstrong, by Ellis] |
4034 | Whether we apply 'cold' or 'hot' to an object is quite separate from its change of temperature [Armstrong] |
8535 | To the claim that every predicate has a property, start by eliminating failure of application of predicate [Armstrong] |
8537 | Tropes fall into classes, because exact similarity is symmetrical and transitive [Armstrong] |
4444 | One moderate nominalist view says that properties and relations exist, but they are particulars [Armstrong] |
18373 | If tropes are non-transferable, then they necessarily belong to their particular substance [Armstrong] |
8538 | Trope theory needs extra commitments, to symmetry and non-transitivity, unless resemblance is exact [Armstrong] |
4445 | If properties and relations are particulars, there is still the problem of how to classify and group them [Armstrong] |
18400 | Properties are not powers - they just have powers [Armstrong] |
14330 | To be realists about dispositions, we can only discuss them through their categorical basis [Armstrong] |
17666 | Actualism means that ontology cannot contain what is merely physically possible [Armstrong] |
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] |
18397 | Powers must result in some non-powers, or there would only be potential without result [Armstrong] |
18399 | How does the power of gravity know the distance it acts over? [Armstrong] |
17678 | Universals are just the repeatable features of a world [Armstrong] |
8506 | Particulars and properties are distinguishable, but too close to speak of a relation [Armstrong] |
4448 | Should we decide which universals exist a priori (through words), or a posteriori (through science)? [Armstrong] |
4032 | The problem of universals is how many particulars can all be of the same 'type' [Armstrong] |
17669 | Realist regularity theories of laws need universals, to pick out the same phenomena [Armstrong] |
8539 | Universals are required to give a satisfactory account of the laws of nature [Armstrong] |
10729 | Universals explain resemblance and causal power [Armstrong, by Oliver] |
17677 | Past, present and future must be equally real if universals are instantiated [Armstrong] |
15442 | Universals are abstractions from their particular instances [Armstrong, by Lewis] |
17686 | Universals are abstractions from states of affairs [Armstrong] |
4446 | It is claimed that some universals are not exemplified by any particular, so must exist separately [Armstrong] |
4442 | Most thinkers now reject self-predication (whiteness is NOT white) so there is no Third Man problem [Armstrong] |
8505 | Refusal to explain why different tokens are of the same type is to be an ostrich [Armstrong] |
10151 | I am a deeply convinced nominalist [Tarski] |
8529 | Deniers of properties and relations rely on either predicates or on classes [Armstrong] |
4440 | 'Resemblance Nominalism' finds that in practice the construction of resemblance classes is hard [Armstrong] |
8532 | Resemblances must be in certain 'respects', and they seem awfully like properties [Armstrong] |
4439 | 'Resemblance Nominalism' says properties are resemblances between classes of particulars [Armstrong] |
4031 | It doesn't follow that because there is a predicate there must therefore exist a property [Armstrong] |
8530 | Change of temperature in objects is quite independent of the predicates 'hot' and 'cold' [Armstrong] |
8536 | We want to know what constituents of objects are grounds for the application of predicates [Armstrong] |
4431 | 'Predicate Nominalism' says that a 'universal' property is just a predicate applied to lots of things [Armstrong] |
4433 | Concept and predicate nominalism miss out some predicates, and may be viciously regressive [Armstrong] |
4432 | 'Concept Nominalism' says a 'universal' property is just a mental concept applied to lots of things [Armstrong] |
8531 | In most sets there is no property common to all the members [Armstrong] |
4436 | 'Class Nominalism' may explain properties if we stick to 'natural' sets, and ignore random ones [Armstrong] |
4434 | 'Class Nominalism' says that properties or kinds are merely membership of a set (e.g. of white things) [Armstrong] |
4435 | 'Class Nominalism' cannot explain co-extensive properties, or sets with random members [Armstrong] |
18371 | The class of similar things is much too big a truthmaker for the feature of a particular [Armstrong] |
4437 | 'Mereological Nominalism' sees whiteness as a huge white object consisting of all the white things [Armstrong] |
4438 | 'Mereological Nominalism' may work for whiteness, but it doesn't seem to work for squareness [Armstrong] |
17668 | It is likely that particulars can be individuated by unique conjunctions of properties [Armstrong] |
15753 | Essences might support Resemblance Nominalism, but they are too coarse and ill-defined [Armstrong] |
18389 | When entities contain entities, or overlap with them, there is 'partial' identity [Armstrong] |
10024 | The type-token distinction is the universal-particular distinction [Armstrong, by Hodes] |
10728 | A thing's self-identity can't be a universal, since we can know it a priori [Armstrong, by Oliver] |
17680 | The identity of a thing with itself can be ruled out as a pseudo-property [Armstrong] |
12033 | An object is identical with itself, and no different indiscernible object can share that [Russell/Whitehead, by Adams,RM] |
15542 | All possibilities are recombinations of properties in the actual world [Armstrong, by Lewis] |
17693 | The necessary/contingent distinction may need to recognise possibilities as real [Armstrong] |
4743 | The truth-maker for a truth must necessitate that truth [Armstrong] |
11003 | The best version of reductionist actualism around is Armstrong's combinatorial account [Armstrong, by Read] |
18388 | Possible worlds don't fix necessities; intrinsic necessities imply the extension in worlds [Armstrong] |
6498 | Armstrong suggests secondary qualities are blurred primary qualities [Armstrong, by Robinson,H] |
7440 | Secondary qualities are microscopic primary qualities of physical things [Armstrong] |
3900 | Maybe experience is not essential to perception, but only to the causing of beliefs [Armstrong, by Scruton] |
10040 | Russell showed, through the paradoxes, that our basic logical intuitions are self-contradictory [Russell/Whitehead, by Gödel] |
4253 | Externalism says knowledge involves a natural relation between the belief state and what makes it true [Armstrong] |
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] |
7437 | Consciousness and experience of qualities are not the same [Armstrong] |
18375 | General truths are a type of negative truth, saying there are no more ravens than black ones [Armstrong] |
5690 | A mental state without belief refutes self-intimation; a belief with no state refutes infallibility [Armstrong, by Shoemaker] |
7434 | Behaviourism is false, but mind is definable as the cause of behaviour [Armstrong] |
7436 | The manifestations of a disposition need never actually exist [Armstrong] |
5493 | If pains are defined causally, and research shows that the causal role is physical, then pains are physical [Armstrong, by Lycan] |
4600 | Armstrong and Lewis see functionalism as an identity of the function and its realiser [Armstrong, by Heil] |
7429 | Causal Functionalism says mental states are apt for producing behaviour [Armstrong] |
7438 | A causal theory of mentality would be improved by a teleological element [Armstrong] |
7431 | The identity of mental states with physical properties is contingent, because the laws of nature are contingent [Armstrong] |
7432 | One mental role might be filled by a variety of physical types [Armstrong] |
21725 | The multiple relations theory says assertions about propositions are about their ingredients [Russell/Whitehead, by Linsky,B] |
23474 | A judgement is a complex entity, of mind and various objects [Russell/Whitehead] |
23455 | The meaning of 'Socrates is human' is completed by a judgement [Russell/Whitehead] |
23480 | The multiple relation theory of judgement couldn't explain the unity of sentences [Morris,M on Russell/Whitehead] |
18275 | Only the act of judging completes the meaning of a statement [Russell/Whitehead] |
17664 | Each subject has an appropriate level of abstraction [Armstrong] |
8533 | Predicates need ontological correlates to ensure that they apply [Armstrong] |
4035 | There must be some explanation of why certain predicates are applicable to certain objects [Armstrong] |
18368 | For all being, there is a potential proposition which expresses its existence and nature [Armstrong] |
18370 | A realm of abstract propositions is causally inert, so has no explanatory value [Armstrong] |
23453 | Propositions as objects of judgement don't exist, because we judge several objects, not one [Russell/Whitehead] |
13345 | Sentences are 'analytical' if every sequence of objects models them [Tarski] |
20407 | Taste is the capacity to judge an object or representation which is thought to be beautiful [Tarski, by Schellekens] |
17692 | We can't deduce the phenomena from the One [Armstrong] |
17689 | Absences might be effects, but surely not causes? [Armstrong] |
18380 | Negative causations supervene on positive causations plus their laws? [Armstrong] |
4798 | In recent writings, Armstrong makes a direct identification of necessitation with causation [Armstrong, by Psillos] |
17682 | A universe couldn't consist of mere laws [Armstrong] |
17662 | Science depends on laws of nature to study unobserved times and spaces [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] |
8541 | Regularities theories are poor on causal connections, counterfactuals and probability [Armstrong] |
8540 | The introduction of sparse properties avoids the regularity theory's problem with 'grue' [Armstrong] |
17681 | The laws of nature link properties with properties [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] |
5492 | How can essences generate the right powers to vary with distance between objects? [Armstrong] |
18401 | The pure present moment is too brief to be experienced [Armstrong] |