193 ideas
18390 | All metaphysical discussion should be guided by a quest for truthmakers [Armstrong] |
18835 | Logic doesn't have a metaphysical basis, but nor can logic give rise to the metaphysics [Rumfitt] |
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] |
18819 | The idea that there are unrecognised truths is basic to our concept of truth [Rumfitt] |
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] |
18826 | 'True at a possibility' means necessarily true if what is said had obtained [Rumfitt] |
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] |
18803 | Semantics for propositions: 1) validity preserves truth 2) non-contradition 3) bivalence 4) truth tables [Rumfitt] |
15544 | If what is actual might have been impossible, we need S4 modal logic [Armstrong, by Lewis] |
12204 | The logic of metaphysical necessity is S5 [Rumfitt] |
18814 | 'Absolute necessity' would have to rest on S5 [Rumfitt] |
18798 | It is the second-order part of intuitionistic logic which actually negates some classical theorems [Rumfitt] |
18799 | Intuitionists can accept Double Negation Elimination for decidable propositions [Rumfitt] |
18396 | The set theory brackets { } assert that the member is a unit [Armstrong] |
18830 | Most set theorists doubt bivalence for the Continuum Hypothesis, but still use classical logic [Rumfitt] |
18393 | For 'there is a class with no members' we don't need the null set as truthmaker [Armstrong] |
18843 | The iterated conception of set requires continual increase in axiom strength [Rumfitt] |
18836 | A set may well not consist of its members; the empty set, for example, is a problem [Rumfitt] |
18837 | A set can be determinate, because of its concept, and still have vague membership [Rumfitt] |
18845 | If the totality of sets is not well-defined, there must be doubt about the Power Set Axiom [Rumfitt] |
11211 | If a sound conclusion comes from two errors that cancel out, the path of the argument must matter [Rumfitt] |
18815 | Logic is higher-order laws which can expand the range of any sort of deduction [Rumfitt] |
9390 | Logic guides thinking, but it isn't a substitute for it [Rumfitt] |
18804 | The case for classical logic rests on its rules, much more than on the Principle of Bivalence [Rumfitt] |
18805 | Classical logic rules cannot be proved, but various lines of attack can be repelled [Rumfitt] |
18827 | If truth-tables specify the connectives, classical logic must rely on Bivalence [Rumfitt] |
12195 | Soundness in argument varies with context, and may be achieved very informally indeed [Rumfitt] |
12199 | There is a modal element in consequence, in assessing reasoning from suppositions [Rumfitt] |
12201 | We reject deductions by bad consequence, so logical consequence can't be deduction [Rumfitt] |
18813 | Logical consequence is a relation that can extended into further statements [Rumfitt] |
18808 | Normal deduction presupposes the Cut Law [Rumfitt] |
18840 | When faced with vague statements, Bivalence is not a compelling principle [Rumfitt] |
12194 | Contradictions include 'This is red and not coloured', as well as the formal 'B and not-B' [Rumfitt] |
11210 | Standardly 'and' and 'but' are held to have the same sense by having the same truth table [Rumfitt] |
18802 | In specifying a logical constant, use of that constant is quite unavoidable [Rumfitt] |
11212 | The sense of a connective comes from primitively obvious rules of inference [Rumfitt] |
12198 | Geometrical axioms in logic are nowadays replaced by inference rules (which imply the logical truths) [Rumfitt] |
18800 | Introduction rules give deduction conditions, and Elimination says what can be deduced [Rumfitt] |
18809 | Logical truths are just the assumption-free by-products of logical rules [Rumfitt] |
18807 | Monotonicity means there is a guarantee, rather than mere inductive support [Rumfitt] |
18842 | Maybe an ordinal is a property of isomorphic well-ordered sets, and not itself a set [Rumfitt] |
18392 | Classes have cardinalities, so their members must all be treated as units [Armstrong] |
17462 | A single object must not be counted twice, which needs knowledge of distinctness (negative identity) [Rumfitt] |
18834 | Infinitesimals do not stand in a determinate order relation to zero [Rumfitt] |
18846 | Cantor and Dedekind aimed to give analysis a foundation in set theory (rather than geometry) [Rumfitt] |
17461 | Some 'how many?' answers are not predications of a concept, like 'how many gallons?' [Rumfitt] |
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] |
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] |
17678 | Universals are just the repeatable features of a world [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] |
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] |
9389 | Vague membership of sets is possible if the set is defined by its concept, not its members [Rumfitt] |
18839 | An object that is not clearly red or orange can still be red-or-orange, which sweeps up problem cases [Rumfitt] |
18838 | The extension of a colour is decided by a concept's place in a network of contraries [Rumfitt] |
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] |
14532 | A distinctive type of necessity is found in logical consequence [Rumfitt, by Hale/Hoffmann,A] |
18816 | Metaphysical modalities respect the actual identities of things [Rumfitt] |
12193 | Logical necessity is when 'necessarily A' implies 'not-A is contradictory' [Rumfitt] |
12200 | A logically necessary statement need not be a priori, as it could be unknowable [Rumfitt] |
18825 | S5 is the logic of logical necessity [Rumfitt] |
12202 | Narrow non-modal logical necessity may be metaphysical, but real logical necessity is not [Rumfitt] |
15542 | All possibilities are recombinations of properties in the actual world [Armstrong, by Lewis] |
18824 | Since possibilities are properties of the world, calling 'red' the determination of a determinable seems right [Rumfitt] |
18828 | If two possibilities can't share a determiner, they are incompatible [Rumfitt] |
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] |
12203 | If a world is a fully determinate way things could have been, can anyone consider such a thing? [Rumfitt] |
18821 | Possibilities are like possible worlds, but not fully determinate or complete [Rumfitt] |
18831 | Medieval logicians said understanding A also involved understanding not-A [Rumfitt] |
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] |
18820 | In English 'evidence' is a mass term, qualified by 'little' and 'more' [Rumfitt] |
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] |
5504 | Maybe we should see persons in four dimensions, with stages or time-slices at an instant [Martin/Barresi] |
5503 | Maybe personal identity is not vital in survival, and other continuations would suffice [Martin/Barresi] |
5502 | Locke's intrinsic view of personal identity has been replaced by an externalist view [Martin/Barresi] |
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] |
17664 | Each subject has an appropriate level of abstraction [Armstrong] |
18817 | We understand conditionals, but disagree over their truth-conditions [Rumfitt] |
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] |
18829 | The truth grounds for 'not A' are the possibilities incompatible with truth grounds for A [Rumfitt] |
11214 | We learn 'not' along with affirmation, by learning to either affirm or deny a sentence [Rumfitt] |
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] |
5505 | For Aristotle the psyche perishes with the body (except possibly 'nous') [Martin/Barresi] |