216 ideas
9218 | Maybe what distinguishes philosophy from science is its pursuit of necessary truths [Sider] |
9408 | Science studies phenomena, but only metaphysics tells us what exists [Mumford] |
14721 | Metaphysical enquiry can survive if its conclusions are tentative [Sider] |
15010 | Your metaphysics is 'cheating' if your ontology won't support the beliefs you accept [Sider] |
14977 | Metaphysics is not about what exists or is true or essential; it is about the structure of reality [Sider] |
14994 | Extreme doubts about metaphysics also threaten to undermine the science of unobservables [Sider] |
15003 | It seems unlikely that the way we speak will give insights into the universe [Sider] |
14986 | Conceptual analysts trust particular intuitions much more than general ones [Sider] |
9429 | Many forms of reasoning, such as extrapolation and analogy, are useful but deductively invalid [Mumford] |
15015 | It seems possible for a correct definition to be factually incorrect, as in defining 'contact' [Sider] |
14981 | Philosophical concepts are rarely defined, and are not understood by means of definitions [Sider] |
14992 | We don't care about plain truth, but truth in joint-carving terms [Sider] |
15012 | Orthodox truthmaker theories make entities fundamental, but that is poor for explanation [Sider] |
13689 | 'Theorems' are formulas provable from no premises at all [Sider] |
13705 | Truth tables assume truth functionality, and are just pictures of truth functions [Sider] |
13706 | Intuitively, deontic accessibility seems not to be reflexive, but to be serial [Sider] |
13710 | In D we add that 'what is necessary is possible'; then tautologies are possible, and contradictions not necessary [Sider] |
13711 | System B introduces iterated modalities [Sider] |
13708 | S5 is the strongest system, since it has the most valid formulas, because it is easy to be S5-valid [Sider] |
13712 | Epistemic accessibility is reflexive, and allows positive and negative introspection (KK and K¬K) [Sider] |
13714 | We can treat modal worlds as different times [Sider] |
13720 | Converse Barcan Formula: □∀αφ→∀α□φ [Sider] |
13718 | The Barcan Formula ∀x□Fx→□∀xFx may be a defect in modal logic [Sider] |
13723 | System B is needed to prove the Barcan Formula [Sider] |
15023 | The Barcan schema implies if X might have fathered something, there is something X might have fathered [Sider] |
13715 | You can employ intuitionist logic without intuitionism about mathematics [Sider] |
15004 | 'Gunk' is an object in which proper parts all endlessly have further proper parts [Sider] |
14984 | Which should be primitive in mereology - part, or overlap? [Sider] |
14980 | There is a real issue over what is the 'correct' logic [Sider] |
15000 | 'It is raining' and 'it is not raining' can't be legislated, so we can't legislate 'p or ¬p' [Sider] |
15020 | Classical logic is good for mathematics and science, but less good for natural language [Sider] |
13678 | The most popular account of logical consequence is the semantic or model-theoretic one [Sider] |
13679 | Maybe logical consequence is more a matter of provability than of truth-preservation [Sider] |
13682 | Maybe logical consequence is impossibility of the premises being true and the consequent false [Sider] |
13680 | Maybe logical consequence is a primitive notion [Sider] |
15029 | Modal accounts of logical consequence are simple necessity, or essential use of logical words [Sider] |
13722 | A 'theorem' is an axiom, or the last line of a legitimate proof [Sider] |
15019 | Define logical constants by role in proofs, or as fixed in meaning, or as topic-neutral [Sider] |
13696 | When a variable is 'free' of the quantifier, the result seems incapable of truth or falsity [Sider] |
13700 | A 'total' function must always produce an output for a given domain [Sider] |
13703 | λ can treat 'is cold and hungry' as a single predicate [Sider] |
13688 | Good axioms should be indisputable logical truths [Sider] |
13687 | No assumptions in axiomatic proofs, so no conditional proof or reductio [Sider] |
13690 | Proof by induction 'on the length of the formula' deconstructs a formula into its accepted atoms [Sider] |
13691 | Induction has a 'base case', then an 'inductive hypothesis', and then the 'inductive step' [Sider] |
15001 | 'Tonk' is supposed to follow the elimination and introduction rules, but it can't be so interpreted [Sider] |
13685 | Natural deduction helpfully allows reasoning with assumptions [Sider] |
13686 | We can build proofs just from conclusions, rather than from plain formulae [Sider] |
13697 | Valuations in PC assign truth values to formulas relative to variable assignments [Sider] |
13684 | The semantical notion of a logical truth is validity, being true in all interpretations [Sider] |
13704 | It is hard to say which are the logical truths in modal logic, especially for iterated modal operators [Sider] |
13724 | In model theory, first define truth, then validity as truth in all models, and consequence as truth-preservation [Sider] |
13698 | In a complete logic you can avoid axiomatic proofs, by using models to show consequences [Sider] |
13699 | Compactness surprisingly says that no contradictions can emerge when the set goes infinite [Sider] |
13701 | A single second-order sentence validates all of arithmetic - but this can't be proved axiomatically [Sider] |
9427 | For Humeans the world is a world primarily of events [Mumford] |
458 | Nothing could come out of nothing, and existence could never completely cease [Empedocles] |
5112 | Empedocles says things are at rest, unless love unites them, or hatred splits them [Empedocles, by Aristotle] |
14760 | Four-dimensionalism sees things and processes as belonging in the same category [Sider] |
15017 | Supervenience is a modal connection [Sider] |
15008 | Is fundamentality in whole propositions (and holistic), or in concepts (and atomic)? [Sider] |
15013 | Tables and chairs have fundamental existence, but not fundamental natures [Sider] |
15014 | Unlike things, stuff obeys unrestricted composition and mereological essentialism [Sider] |
14334 | Modest realism says there is a reality; the presumptuous view says we can accurately describe it [Mumford] |
14306 | Anti-realists deny truth-values to all statements, and say evidence and ontology are inseparable [Mumford] |
15009 | We must distinguish 'concrete' from 'abstract' and necessary states of affairs. [Sider] |
13692 | A 'precisification' of a trivalent interpretation reduces it to a bivalent interpretation [Sider] |
13695 | Supervaluational logic is classical, except when it adds the 'Definitely' operator [Sider] |
13693 | A 'supervaluation' assigns further Ts and Fs, if they have been assigned in every precisification [Sider] |
13694 | We can 'sharpen' vague terms, and then define truth as true-on-all-sharpenings [Sider] |
14983 | Accept the ontology of your best theory - and also that it carves nature at the joints [Sider] |
13683 | A relation is a feature of multiple objects taken together [Sider] |
14978 | A property is intrinsic if an object alone in the world can instantiate it [Sider] |
14333 | Dispositions and categorical properties are two modes of presentation of the same thing [Mumford] |
14336 | Categorical predicates are those unconnected to functions [Mumford] |
14315 | Categorical properties and dispositions appear to explain one another [Mumford] |
14332 | There are four reasons for seeing categorical properties as the most fundamental [Mumford] |
14194 | Proper ontology should only use categorical (actual) properties, not hypothetical ones [Sider] |
14302 | A lead molecule is not leaden, and macroscopic properties need not be microscopically present [Mumford] |
14995 | Predicates can be 'sparse' if there is a universal, or if there is a natural property or relation [Sider] |
9446 | Properties are just natural clusters of powers [Mumford] |
14294 | Dispositions are attacked as mere regularities of events, or place-holders for unknown properties [Mumford] |
14310 | Dispositions are classifications of properties by functional role [Mumford] |
14317 | I say the categorical base causes the disposition manifestation [Mumford] |
14316 | If dispositions have several categorical realisations, that makes the two separate [Mumford] |
14313 | All properties must be causal powers (since they wouldn't exist otherwise) [Mumford] |
14318 | Intrinsic properties are just causal powers, and identifying a property as causal is then analytic [Mumford] |
14293 | Dispositions are ascribed to at least objects, substances and persons [Mumford] |
14326 | Unlike categorical bases, dispositions necessarily occupy a particular causal role [Mumford] |
14298 | Dispositions can be contrasted either with occurrences, or with categorical properties [Mumford] |
14314 | If dispositions are powers, background conditions makes it hard to say what they do [Mumford] |
14325 | Maybe dispositions can replace powers in metaphysics, as what induces property change [Mumford] |
14312 | Orthodoxy says dispositions entail conditionals (rather than being equivalent to them) [Mumford] |
14291 | Dispositions are not just possibilities - they are features of actual things [Mumford] |
14299 | There could be dispositions that are never manifested [Mumford] |
14323 | If every event has a cause, it is easy to invent a power to explain each case [Mumford] |
14328 | Traditional powers initiate change, but are mysterious between those changes [Mumford] |
14331 | Categorical eliminativists say there are no dispositions, just categorical states or mechanisms [Mumford] |
9435 | A 'porridge' nominalist thinks we just divide reality in any way that suits us [Mumford] |
9447 | If properties are clusters of powers, this can explain why properties resemble in degrees [Mumford] |
14745 | If sortal terms fix the kind and the persistence conditions, we need to know what kinds there are [Sider] |
13209 | There is no coming-to-be of anything, but only mixing and separating [Empedocles, by Aristotle] |
18617 | Substances, unlike aggregates, can survive a change of parts [Mumford] |
14740 | If Tib is all of Tibbles bar her tail, when Tibbles loses her tail, two different things become one [Sider] |
14752 | Artists 'create' statues because they are essentially statues, and so lack identity with the lump of clay [Sider] |
14743 | The stage view of objects is best for dealing with coincident entities [Sider] |
14747 | 'Composition as identity' says that an object just is the objects which compose it [Sider] |
14295 | Many artefacts have dispositional essences, which make them what they are [Mumford] |
14757 | Mereological essentialism says an object's parts are necessary for its existence [Sider] |
12248 | How can we show that a universally possessed property is an essential property? [Mumford] |
15026 | Essence (even if nonmodal) is not fundamental in metaphysics [Sider] |
14727 | Three-dimensionalists assert 'enduring', being wholly present at each moment, and deny 'temporal parts' [Sider] |
14738 | Some might say that its inconsistency with time travel is a reason to favour three-dimensionalism [Sider] |
14726 | Four-dimensionalists assert 'temporal parts', 'perduring', and being spread out over time [Sider] |
14728 | 4D says intrinsic change is difference between successive parts [Sider] |
14729 | 4D says each spatiotemporal object must have a temporal part at every moment at which it exists [Sider] |
14730 | Temporal parts exist, but are not prior building blocks for objects [Sider] |
14731 | Temporal parts are instantaneous [Sider] |
14758 | How can an instantaneous stage believe anything, if beliefs take time? [Sider] |
14762 | Four-dimensionalism says temporal parts are caused (through laws of motion) by previous temporal parts [Sider] |
14741 | The ship undergoes 'asymmetric' fission, where one candidate is seen as stronger [Sider] |
457 | Substance is not created or destroyed in mortals, but there is only mixing and exchange [Empedocles] |
13702 | The identity of indiscernibles is necessarily true, if being a member of some set counts as a property [Sider] |
14754 | If you say Leibniz's Law doesn't apply to 'timebound' properties, you are no longer discussing identity [Sider] |
13721 | 'Strong' necessity in all possible worlds; 'weak' necessity in the worlds where the relevant objects exist [Sider] |
13707 | Maybe metaphysical accessibility is intransitive, if a world in which I am a frog is impossible [Sider] |
13709 | Logical truths must be necessary if anything is [Sider] |
18618 | Maybe possibilities are recombinations of the existing elements of reality [Mumford] |
18619 | Combinatorial possibility has to allow all elements to be combinable, which seems unlikely [Mumford] |
18620 | Combinatorial possibility relies on what actually exists (even over time), but there could be more [Mumford] |
13716 | 'If B hadn't shot L someone else would have' if false; 'If B didn't shoot L, someone else did' is true [Sider] |
14309 | Truth-functional conditionals can't distinguish whether they are causal or accidental [Mumford] |
14311 | Dispositions are not equivalent to stronger-than-material conditionals [Mumford] |
15030 | Humeans say that we decide what is necessary [Sider] |
15031 | Modal terms in English are entirely contextual, with no modality outside the language [Sider] |
15027 | If truths are necessary 'by convention', that seems to make them contingent [Sider] |
15028 | Conventionalism doesn't seem to apply to examples of the necessary a posteriori [Sider] |
15033 | Humeans says mathematics and logic are necessary because that is how our concept of necessity works [Sider] |
15025 | The world does not contain necessity and possibility - merely how things are [Sider] |
13717 | Transworld identity is not a problem in de dicto sentences, which needn't identify an individual [Sider] |
14763 | Counterparts rest on similarity, so there are many such relations in different contexts [Sider] |
13719 | Barcan Formula problem: there might have been a ghost, despite nothing existing which could be a ghost [Sider] |
462 | One vision is produced by both eyes [Empedocles] |
14988 | A theory which doesn't fit nature is unexplanatory, even if it is true [Sider] |
14982 | If I used Ramsey sentences to eliminate fundamentality from my theory, that would be a real loss [Sider] |
14989 | Problem predicates in induction don't reflect the structure of nature [Sider] |
14997 | Two applications of 'grue' do not guarantee a similarity between two things [Sider] |
14990 | Bayes produces weird results if the prior probabilities are bizarre [Sider] |
15005 | Explanations must cite generalisations [Sider] |
14319 | Nomothetic explanations cite laws, and structural explanations cite mechanisms [Mumford] |
14342 | General laws depend upon the capacities of particulars, not the other way around [Mumford] |
14322 | If fragile just means 'breaks when dropped', it won't explain a breakage [Mumford] |
14337 | Maybe dispositions can replace the 'laws of nature' as the basis of explanation [Mumford] |
14343 | To avoid a regress in explanations, ungrounded dispositions will always have to be posited [Mumford] |
14320 | Subatomic particles may terminate explanation, if they lack structure [Mumford] |
15011 | If the ultimate explanation is a list of entities, no laws, patterns or mechanisms can be cited [Sider] |
14324 | Ontology is unrelated to explanation, which concerns modes of presentation and states of knowledge [Mumford] |
15018 | Intentionality is too superficial to appear in the catalogue of ultimate physics [Sider] |
22765 | Wisdom and thought are shared by all things [Empedocles] |
1524 | For Empedocles thinking is almost identical to perception [Empedocles, by Theophrastus] |
14999 | Prior to conventions, not all green things were green? [Sider] |
14998 | Conventions are contingent and analytic truths are necessary, so that isn't their explanation [Sider] |
15016 | Analyticity has lost its traditional role, which relied on truth by convention [Sider] |
552 | Empedocles said good and evil were the basic principles [Empedocles, by Aristotle] |
589 | 'Nature' is just a word invented by people [Empedocles] |
21823 | The principle of 'Friendship' in Empedocles is the One, and is bodiless [Empedocles, by Plotinus] |
2680 | Empedocles said that there are four material elements, and two further creative elements [Empedocles, by Aristotle] |
6002 | Empedocles says bone is water, fire and earth in ratio 2:4:2 [Empedocles, by Inwood] |
13207 | Fire, Water, Air and Earth are elements, being simple as well as homoeomerous [Empedocles, by Aristotle] |
459 | All change is unity through love or division through hate [Empedocles] |
13218 | The elements combine in coming-to-be, but how do the elements themselves come-to-be? [Aristotle on Empedocles] |
13225 | Love and Strife only explain movement if their effects are distinctive [Aristotle on Empedocles] |
460 | If the one Being ever diminishes it would no longer exist, and what could ever increase it? [Empedocles] |
14344 | Natural kinds, such as electrons, all behave the same way because we divide them by dispositions [Mumford] |
19068 | Causation interests us because we want to explain change [Mumford] |
9430 | Singular causes, and identities, might be necessary without falling under a law [Mumford] |
9445 | We can give up the counterfactual account if we take causal language at face value [Mumford] |
9443 | It is only properties which are the source of necessity in the world [Mumford] |
14338 | In the 'laws' view events are basic, and properties are categorical, only existing when manifested [Mumford] |
9444 | There are four candidates for the logical form of law statements [Mumford] |
14339 | Without laws, how can a dispositionalist explain general behaviour within kinds? [Mumford] |
14341 | Dretske and Armstrong base laws on regularities between individual properties, not between events [Mumford] |
9441 | Regularity laws don't explain, because they have no governing role [Mumford] |
14340 | It is a regularity that whenever a person sneezes, someone (somewhere) promptly coughs [Mumford] |
9416 | Regularities are more likely with few instances, and guaranteed with no instances! [Mumford] |
9431 | Pure regularities are rare, usually only found in idealized conditions [Mumford] |
9415 | Would it count as a regularity if the only five As were also B? [Mumford] |
9422 | If the best system describes a nomological system, the laws are in nature, not in the description [Mumford] |
9421 | The best systems theory says regularities derive from laws, rather than constituting them [Mumford] |
9432 | Laws of nature are necessary relations between universal properties, rather than about particulars [Mumford] |
9433 | If laws can be uninstantiated, this favours the view of them as connecting universals [Mumford] |
14345 | The necessity of an electron being an electron is conceptual, and won't ground necessary laws [Mumford] |
9434 | Laws of nature are just the possession of essential properties by natural kinds [Mumford] |
14307 | Some dispositions are so far unknown, until we learn how to manifest them [Mumford] |
9437 | To distinguish accidental from essential properties, we must include possible members of kinds [Mumford] |
9439 | The Central Dilemma is how to explain an internal or external view of laws which govern [Mumford] |
9412 | You only need laws if you (erroneously) think the world is otherwise inert [Mumford] |
14985 | The notion of law doesn't seem to enhance physical theories [Sider] |
9411 | There are no laws of nature in Aristotle; they became standard with Descartes and Newton [Mumford] |
14987 | Many of the key theories of modern physics do not appear to be 'laws' [Sider] |
14725 | Maybe motion is a dynamical quantity intrinsic to a thing at a particular time [Sider] |
14991 | Space has real betweenness and congruence structure (though it is not the Euclidean concepts) [Sider] |
14735 | Space is 3D and lacks a direction; time seems connected to causation [Sider] |
15021 | The central question in the philosophy of time is: How alike are time and space? [Sider] |
15024 | The spotlight theorists accepts eternal time, but with a spotlight of the present moving across it [Sider] |
14722 | Between presentism and eternalism is the 'growing block' view - the past is real, the future is not [Sider] |
14756 | For Presentists there must always be a temporal vantage point for any description [Sider] |
14724 | Presentists must deny truths about multiple times [Sider] |
14723 | Talk using tenses can be eliminated, by reducing it to indexical connections for an utterance [Sider] |
14736 | The B-theory is adequate, except that it omits to say which time is present [Sider] |
14734 | The B-series involves eternalism, and the reduction of tense [Sider] |
5090 | Maybe bodies are designed by accident, and the creatures that don't work are destroyed [Empedocles, by Aristotle] |
461 | God is a pure, solitary, and eternal sphere [Empedocles] |
466 | God is pure mind permeating the universe [Empedocles] |
1719 | In Empedocles' theory God is ignorant because, unlike humans, he doesn't know one of the elements (strife) [Aristotle on Empedocles] |
1522 | It is wretched not to want to think clearly about the gods [Empedocles] |