156 ideas
| 16325 | Analysis rests on natural language, but its ideal is a framework which revises language [Halbach] |
| 6779 | Instrumentalists say distinctions between observation and theory vanish with ostensive definition [Bird] |
| 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] |
| 16324 | Any definition of truth requires a metalanguage [Halbach] |
| 15647 | Truth definitions don't produce a good theory, because they go beyond your current language [Halbach] |
| 16293 | Traditional definitions of truth often make it more obscure, rather than less [Halbach] |
| 16301 | If people have big doubts about truth, a definition might give it more credibility [Halbach] |
| 15649 | In semantic theories of truth, the predicate is in an object-language, and the definition in a metalanguage [Halbach] |
| 16297 | Semantic theories avoid Tarski's Theorem by sticking to a sublanguage [Halbach] |
| 16337 | Disquotational truth theories are short of deductive power [Halbach] |
| 15648 | Instead of a truth definition, add a primitive truth predicate, and axioms for how it works [Halbach] |
| 15655 | Should axiomatic truth be 'conservative' - not proving anything apart from implications of the axioms? [Halbach] |
| 15654 | If truth is defined it can be eliminated, whereas axiomatic truth has various commitments [Halbach] |
| 16294 | Axiomatic truth doesn't presuppose a truth-definition, though it could admit it at a later stage [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] |
| 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] |
| 16322 | CT proves PA consistent, which PA can't do on its own, so CT is not conservative over PA [Halbach] |
| 16305 | We know a complete axiomatisation of truth is not feasible [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] |
| 15650 | Axiomatic theories of truth need a weak logical framework, and not a strong metatheory [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 than 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] |
| 15656 | Deflationists say truth merely serves to express infinite conjunctions [Halbach] |
| 16338 | Deflationism says truth is a disquotation device to express generalisations, adding no new knowledge [Halbach] |
| 16317 | The main problem for deflationists is they can express generalisations, but not prove them [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] |
| 16320 | Some say deflationism is axioms which are conservative over the base theory [Halbach] |
| 9449 | The plausible Barcan formula implies modality in the actual world [Bird] |
| 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] |
| 15657 | To prove the consistency of set theory, we must go beyond set theory [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] |
| 15652 | We can use truth instead of ontologically loaded second-order comprehension assumptions about properties [Halbach] |
| 15651 | Instead of saying x has a property, we can say a formula is true of x - as long as we have 'true' [Halbach] |
| 16310 | A theory is some formulae and all of their consequences [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] |
| 16341 | Normally we only endorse a theory if we believe it to be sound [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 recent truth-theories are exploring type-free [Halbach] |
| 9501 | If all existents are causally active, that excludes abstracta and causally isolated objects [Bird] |
| 16345 | That Peano arithmetic is interpretable in ZF set theory is taken by philosophers as a reduction [Halbach] |
| 9500 | If naturalism refers to supervenience, that leaves necessary entities untouched [Bird] |
| 6780 | Anti-realism is more plausible about laws than about entities and theories [Bird] |
| 9502 | There might be just one fundamental natural property [Bird] |
| 9477 | Categorical properties are not modally fixed, but change across possible worlds [Bird] |
| 9490 | The categoricalist idea is that a property is only individuated by being itself [Bird] |
| 9495 | If we abstractly define a property, that doesn't mean some object could possess it [Bird] |
| 9492 | Categoricalists take properties to be quiddities, with no essential difference between them [Bird] |
| 9503 | To name an abundant property is either a Fregean concept, or a simple predicate [Bird] |
| 14540 | Only real powers are fundamental [Bird, by Mumford/Anjum] |
| 9450 | If all properties are potencies, and stimuli and manifestation characterise them, there is a regress [Bird] |
| 9498 | The essence of a potency involves relations, e.g. mass, to impressed force and acceleration [Bird] |
| 9474 | A disposition is finkish if a time delay might mean the manifestation fizzles out [Bird] |
| 9475 | A robust pot attached to a sensitive bomb is not fragile, but if struck it will easily break [Bird] |
| 9499 | Megarian actualists deny unmanifested dispositions [Bird] |
| 9486 | Why should a universal's existence depend on instantiation in an existing particular? [Bird] |
| 9472 | Resemblance itself needs explanation, presumably in terms of something held in common [Bird] |
| 16346 | Maybe necessity is a predicate, not the usual operator, to make it more like truth [Halbach] |
| 9482 | If the laws necessarily imply p, that doesn't give a new 'nomological' necessity [Bird] |
| 9481 | Logical necessitation is not a kind of necessity; George Orwell not being Eric Blair is not a real possibility [Bird] |
| 6796 | Subjective probability measures personal beliefs; objective probability measures the chance of an event happening [Bird] |
| 6797 | Objective probability of tails measures the bias of the coin, not our beliefs about it [Bird] |
| 9505 | Empiricist saw imaginability and possibility as close, but now they seem remote [Bird] |
| 9491 | Haecceitism says identity is independent of qualities and without essence [Bird] |
| 6800 | Many philosophers rate justification as a more important concept than knowledge [Bird] |
| 6786 | As science investigates more phenomena, the theories it needs decreases [Bird] |
| 6792 | If theories need observation, and observations need theories, how do we start? [Bird] |
| 6757 | Explanation predicts after the event; prediction explains before the event [Bird] |
| 6805 | Relativity ousted Newtonian mechanics despite a loss of simplicity [Bird] |
| 6777 | Realists say their theories involve truth and the existence of their phenomena [Bird] |
| 6804 | There is no agreement on scientific method - because there is no such thing [Bird] |
| 6778 | Instrumentalists regard theories as tools for prediction, with truth being irrelevant [Bird] |
| 6775 | Induction is inference to the best explanation, where the explanation is a law [Bird] |
| 6791 | If Hume is right about induction, there is no scientific knowledge [Bird] |
| 6790 | Anything justifying inferences from observed to unobserved must itself do that [Bird] |
| 6738 | Any conclusion can be drawn from an induction, if we use grue-like predicates [Bird] |
| 6739 | Several months of observing beech trees supports the deciduous and evergreen hypotheses [Bird] |
| 6799 | We normally learn natural kinds from laws, but Goodman shows laws require prior natural kinds [Bird] |
| 6798 | Bayesianism claims to find rationality and truth in induction, and show how science works [Bird] |
| 6752 | The objective component of explanations is the things that must exist for the explanation [Bird] |
| 6754 | We talk both of 'people' explaining things, and of 'facts' explaining things [Bird] |
| 9487 | We can't reject all explanations because of a regress; inexplicable A can still explain B [Bird] |
| 6750 | Explanations are causal, nomic, psychological, psychoanalytic, Darwinian or functional [Bird] |
| 6761 | Contrastive explanations say why one thing happened but not another [Bird] |
| 6758 | 'Covering law' explanations only work if no other explanations are to be found [Bird] |
| 6759 | Livers always accompany hearts, but they don't explain hearts [Bird] |
| 20653 | Six reduction levels: groups, lives, cells, molecules, atoms, particles [Putnam/Oppenheim, by Watson] |
| 6756 | Probabilistic-statistical explanations don't entail the explanandum, but makes it more likely [Bird] |
| 6760 | An operation might reduce the probability of death, yet explain a death [Bird] |
| 6785 | Inference to the Best Explanation is done with facts, so it has to be realist [Bird] |
| 6788 | Maybe bad explanations are the true ones, in this messy world [Bird] |
| 6787 | Which explanation is 'best' is bound to be subjective, and no guide to truth [Bird] |
| 6751 | Maybe explanation is so subjective that it cannot be a part of science [Bird] |
| 17527 | Causation seems to be an innate concept (or acquired very early) [Bird] |
| 16298 | We need propositions to ascribe the same beliefs to people with different languages [Halbach] |
| 6776 | Natural kinds are those that we use in induction [Bird] |
| 6767 | Rubies and sapphires are both corundum, with traces of metals varying their colours [Bird] |
| 6768 | Tin is not one natural kind, but appears to be 21, depending on isotope [Bird] |
| 6771 | Natural kinds may overlap, or be sub-kinds of one another [Bird] |
| 6770 | Membership of a purely random collection cannot be used as an explanation [Bird] |
| 6773 | If F is a universal appearing in a natural law, then Fs form a natural kind [Bird] |
| 6769 | In the Kripke-Putnam view only nuclear physicists can know natural kinds [Bird] |
| 6774 | Darwinism suggests that we should have a native ability to detect natural kinds [Bird] |
| 6764 | Nominal essence of a natural kind is the features that make it fit its name [Bird] |
| 6766 | Jadeite and nephrite are superficially identical, but have different composition [Bird] |
| 6808 | Reference to scientific terms is by explanatory role, not by descriptions [Bird] |
| 17528 | The dispositional account explains causation, as stimulation and manifestation of dispositions [Bird] |
| 9493 | We should explain causation by powers, not powers by causation [Bird] |
| 6753 | Laws are more fundamental in science than causes, and laws will explain causes [Bird] |
| 9494 | Singularism about causes is wrong, as the universals involved imply laws [Bird] |
| 17526 | The counterfactual approach makes no distinction between cause and pre-condition [Bird] |
| 6762 | Newton's laws cannot be confirmed individually, but only in combinations [Bird] |
| 6763 | Parapsychology is mere speculation, because it offers no mechanisms for its working [Bird] |
| 6772 | Existence requires laws, as inertia or gravity are needed for mass or matter [Bird] |
| 9507 | Laws are explanatory relationships of things, which supervene on their essences [Bird] |
| 9488 | Laws are either disposition regularities, or relations between properties [Bird] |
| 6746 | There may be many laws, each with only a few instances [Bird] |
| 6740 | 'All uranium lumps are small' is a law, but 'all gold lumps are small' is not [Bird] |
| 6741 | There can be remarkable uniformities in nature that are purely coincidental [Bird] |
| 6742 | A law might have no instances, if it was about things that only exist momentarily [Bird] |
| 6743 | If laws are just instances, the law should either have gaps, or join the instances arbitrarily [Bird] |
| 6744 | Where is the regularity in a law predicting nuclear decay? [Bird] |
| 6747 | Laws cannot explain instances if they are regularities, as something can't explain itself [Bird] |
| 6748 | Similar appearance of siblings is a regularity, but shared parents is what links them [Bird] |
| 6749 | We can only infer a true regularity if something binds the instances together [Bird] |
| 6803 | If we only infer laws from regularities among observations, we can't infer unobservable entities. [Bird] |
| 6801 | Accidental regularities are not laws, and an apparent regularity may not be actual [Bird] |
| 9496 | That other diamonds are hard does not explain why this one is [Bird] |
| 9479 | Dispositional essentialism says laws (and laws about laws) are guaranteed regularities [Bird] |
| 6745 | A regularity is only a law if it is part of a complete system which is simple and strong [Bird] |
| 6802 | With strange enough predicates, anything could be made out to be a regularity [Bird] |
| 9473 | Laws cannot offer unified explanations if they don't involve universals [Bird] |
| 9484 | If the universals for laws must be instantiated, a vanishing particular could destroy a law [Bird] |
| 9506 | Salt necessarily dissolves in water, because of the law which makes the existence of salt possible [Bird] |
| 23713 | Most laws supervene on fundamental laws, which are explained by basic powers [Bird, by Friend/Kimpton-Nye] |
| 6789 | If flame colour is characteristic of a metal, that is an empirical claim needing justification [Bird] |
| 9489 | Essentialism can't use conditionals to explain regularities, because of possible interventions [Bird] |
| 6807 | In Newton mass is conserved, but in Einstein it can convert into energy [Bird] |
| 9504 | The relational view of space-time doesn't cover times and places where things could be [Bird] |