186 ideas
| 13860 | We can only learn from philosophers of the past if we accept the risk of major misrepresentation [Wright,C] |
| Full Idea: We can learn from the work of philosophers of other periods only if we are prepared to run the risk of radical and almost inevitable misrepresentation of his thought. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], Pref) | |
| A reaction: This sounds about right, and a motto for my own approach to Aristotle and Leibniz, but I see the effort as more collaborative than this suggests. Professional specialists in older philosophers are a vital part of the team. Read them! |
| 15357 | Philosophy is the most general intellectual discipline [Horsten] |
| Full Idea: Philosophy is the most general intellectual discipline. | |
| From: Leon Horsten (The Tarskian Turn [2011], 05.1) | |
| A reaction: Very simple, but exactly how I see the subject. It is continuous with the sciences, and tries to give an account of nature, but operating at an extreme level of generality. It must respect the findings of science, but offer bold interpretations. |
| 6779 | Instrumentalists say distinctions between observation and theory vanish with ostensive definition [Bird] |
| Full Idea: Instrumentalists treat the theoretical/non-theoretical and the observational/non-observational distinctions as the same, ..because they think words get their meaning by way of ostensive definition. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.4) | |
| A reaction: To be honest, I'm not sure I quite understand this, but it sounds interesting... Ostensive definition seems to match the pragmatic spirit of instrumentalism (for which, see Idea 6778). Bird explains it all more fully. |
| 13883 | The best way to understand a philosophical idea is to defend it [Wright,C] |
| Full Idea: The most productive way in which to attempt an understanding of any philosophical idea is to work on its defence. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 1.vii) | |
| A reaction: Very nice. The key point is that this brings greater understanding than working on attacking an idea, which presumably has the dangers of caricature, straw men etc. It is the Socratic insight that dialectic is the route to wisdom. |
| 15352 | A definition should allow the defined term to be eliminated [Horsten] |
| Full Idea: A definition allows a defined term to be eliminated in every context in which it appears. | |
| From: Leon Horsten (The Tarskian Turn [2011], 04.2) | |
| A reaction: To do that, a definition had better be incredibly comprehensive, so that no nice nuance of the original term is thrown out. |
| 10142 | The attempt to define numbers by contextual definition has been revived [Wright,C, by Fine,K] |
| Full Idea: Frege gave up on the attempt to introduce natural numbers by contextual definition, but the project has been revived by neo-logicists. | |
| From: report of Crispin Wright (Frege's Concept of Numbers as Objects [1983]) by Kit Fine - The Limits of Abstraction II |
| 10882 | Predicative definitions only refer to entities outside the defined collection [Horsten] |
| Full Idea: Definitions are called 'predicative', and are considered sound, if they only refer to entities which exist independently from the defined collection. | |
| From: Leon Horsten (Philosophy of Mathematics [2007], §2.4) |
| 15324 | Semantic theories of truth seek models; axiomatic (syntactic) theories seek logical principles [Horsten] |
| Full Idea: There are semantical theories of truth, concerned with models for languages containing the truth predicate, and axiomatic (or syntactic) theories, interested in basic logical principles governing the concept of truth. | |
| From: Leon Horsten (The Tarskian Turn [2011], 01.1) | |
| A reaction: This is the map of contemporary debates, which seem now to have given up talking about 'correspondence', 'coherence' etc. |
| 15323 | Truth is a property, because the truth predicate has an extension [Horsten] |
| Full Idea: I take truth to be a property because the truth predicate has an extension - the collection of all true sentences - and this collection does not (unlike the 'extension' of 'exists') consist of everything, or even of all sentences. | |
| From: Leon Horsten (The Tarskian Turn [2011], 01.1) | |
| A reaction: He concedes that it may be an 'uninteresting' property. My problem is always that I am unconvinced that truth is tied to sentences. I can make perfect sense of animal thoughts being right or wrong. Extension of mental propositions? |
| 15374 | Truth has no 'nature', but we should try to describe its behaviour in inferences [Horsten] |
| Full Idea: We should not aim at describing the nature of truth because there is no such thing. Rather, we should aim at describing the inferential behaviour of truth. | |
| From: Leon Horsten (The Tarskian Turn [2011], 10.2.3) |
| 15348 | Propositions have sentence-like structures, so it matters little which bears the truth [Horsten] |
| Full Idea: It makes little difference, at least in extensional contexts, whether the truth bearers are propositions or sentences (or assertions). Even if the bearers are propositions rather than sentences, propositions are structured rather like sentences. | |
| From: Leon Horsten (The Tarskian Turn [2011], 02.4) | |
| A reaction: The 'extensional' context means you are only talking about the things that are referred to, and not about the way this is expressed. I prefer propositions, but this is an interesting point. |
| 15333 | Modern correspondence is said to be with the facts, not with true propositions [Horsten] |
| Full Idea: Modern correspondence theorists no longer take things to correspond to true propositions; they consider facts to be the truthmakers of propositions. | |
| From: Leon Horsten (The Tarskian Turn [2011], 02.1) | |
| A reaction: If we then define facts as the way certain things are, independently from our thinking about it, at least we seem to be avoiding circularity. Not much point in correspondence accounts if you are not a robust realist (like me). [14,000th idea, 23/4/12!] |
| 15337 | The correspondence 'theory' is too vague - about both 'correspondence' and 'facts' [Horsten] |
| Full Idea: The principle difficulty of the correspondence theory of truth is its vagueness. It is too vague to be called a theory until more information is given about what is meant by the terms 'correspondence' and 'fact'. Facts can involve a heavy ontology. | |
| From: Leon Horsten (The Tarskian Turn [2011], 02.1) | |
| A reaction: I see nothing here to make me give up my commitment to the correspondence view of truth, though it sounds as if I will have to give up the word 'theory' in that context. Truth is so obviously about thought fitting reality that there is nothing to discuss. |
| 15334 | The coherence theory allows multiple coherent wholes, which could contradict one another [Horsten] |
| Full Idea: The coherence theory seems too liberal. It seems there can be more than one systematic whole which, while being internally coherent, contradict each other, and thus cannot all be true. Coherence is a necessary but not sufficient condition for truth. | |
| From: Leon Horsten (The Tarskian Turn [2011], 02.1) | |
| A reaction: This is a modern post-Tarski axiomatic truth theorist making very short work indeed of the coherence theory of truth. I take Horsten to be correct. |
| 15336 | The pragmatic theory of truth is relative; useful for group A can be useless for group B [Horsten] |
| Full Idea: The pragmatic theory is unsatisfactory because usefulness is a relative notion. One theory can be useful to group A while being thoroughly impractical for group B. This would make the theory both truth and false. | |
| From: Leon Horsten (The Tarskian Turn [2011], 02.1) | |
| A reaction: This objection, along with the obvious fact that certain falsehoods can be very useful, would seem to rule pragmatism out as a theory of truth. It is, in fact, an abandonment of truth. |
| 15354 | Tarski's hierarchy lacks uniform truth, and depends on contingent factors [Horsten] |
| Full Idea: According to the Tarskian hierarchical conception, truth is not a uniform notion. ...Also Kripke has emphasised that the level of a token of the truth predicate can depend on contingent factors, such as what else has been said by a speaker. | |
| From: Leon Horsten (The Tarskian Turn [2011], 04.5) |
| 15340 | Tarski Bi-conditional: if you'll assert φ you'll assert φ-is-true - and also vice versa [Horsten] |
| Full Idea: The axiom schema 'Sentence "phi;" is true iff φ' is the (unrestricted) Tarski-Biconditional, and is motivated by the thought that if you are willing to assume or outright assert that φ, you will assert that φ is true - and also vice versa. | |
| From: Leon Horsten (The Tarskian Turn [2011], 02.2) | |
| A reaction: Very helpful! Most people are just bewildered by the Tarski bi-conditional ('"Snow is white"...), but this formulation nicely shows its minimal character while showing that it really does say something. It says what truths and truth-claims commit you to. |
| 15345 | Semantic theories have a regress problem in describing truth in the languages for the models [Horsten] |
| Full Idea: Semantic theories give a class of models with a truth predicate, ...but Tarski taught us that this needs a more encompassing framework than its language...so how is the semantics of the framework expressed? The model route has a regress. | |
| From: Leon Horsten (The Tarskian Turn [2011], 02.3) | |
| A reaction: [compressed] So this regress problem, of endless theories of truth going up the hierarchy, is Horsten's main reason for opting for axiomatic theories, which he then tries to strengthen, so that they are not quite so deflated. |
| 15373 | Axiomatic approaches avoid limiting definitions to avoid the truth predicate, and limited sizes of models [Horsten] |
| Full Idea: An adequate definition of truth can only be given for the fragment of our language that does not contain the truth predicate. A model can never encompass the whole of the domain of discourse of our language. The axiomatic approach avoids these problems. | |
| From: Leon Horsten (The Tarskian Turn [2011], 10.1) |
| 15346 | Axiomatic approaches to truth avoid the regress problem of semantic theories [Horsten] |
| Full Idea: The axiomatic approach to truth does not suffer from the regress problem. | |
| From: Leon Horsten (The Tarskian Turn [2011], 02.3) | |
| A reaction: See Idea 15345 for the regress problem. The difficulty then seems to be that axiomatic approaches lack expressive power, so the hunt is on for a set of axioms which will do a decent job. Fun work, if you can cope with it. |
| 15371 | An axiomatic theory needs to be of maximal strength, while being natural and sound [Horsten] |
| Full Idea: The challenge is to find the arithmetically strongest axiomatical truth theory that is both natural and truth-theoretically sound. | |
| From: Leon Horsten (The Tarskian Turn [2011], 07.7) |
| 15332 | 'Reflexive' truth theories allow iterations (it is T that it is T that p) [Horsten] |
| Full Idea: A theory of truth is 'reflexive' if it allows us to prove truth-iterations ("It is true that it is true that so-and-so"). | |
| From: Leon Horsten (The Tarskian Turn [2011], 01.4) |
| 15361 | A good theory of truth must be compositional (as well as deriving biconditionals) [Horsten] |
| Full Idea: Deriving many Tarski-biconditionals is not a sufficient condition for being a good theory of truth. A good theory of truth must in addition do justice to the compositional nature of truth. | |
| From: Leon Horsten (The Tarskian Turn [2011], 06.1) |
| 15350 | The Naïve Theory takes the bi-conditionals as axioms, but it is inconsistent, and allows the Liar [Horsten] |
| Full Idea: The Naïve Theory of Truth collects all the Tarski bi-conditionals of a language and takes them as axioms. But no consistent theory extending Peano arithmetic can prove all of them. It is inconsistent, and even formalises the liar paradox. | |
| From: Leon Horsten (The Tarskian Turn [2011], 03.5.2) | |
| A reaction: [compressed] This looks to me like the account of truth that Davidson was working with, since he just seemed to be compiling bi-conditionals for tricky cases. (Wrong! He championed the Compositional Theory, Horsten p.71) |
| 15351 | Axiomatic theories take truth as primitive, and propose some laws of truth as axioms [Horsten] |
| Full Idea: In the axiomatic approach we take the truth predicate to express an irreducible, primitive notion. The meaning of the truth predicate is partially explicated by proposing certain laws of truth as basic principles, as axioms. | |
| From: Leon Horsten (The Tarskian Turn [2011], 04.2) | |
| A reaction: Judging by Horsten's book, this is a rather fruitful line of enquiry, but it still seems like a bit of a defeat to take truth as 'primitive'. Presumably you could add some vague notion of correspondence as the background picture. |
| 15367 | By adding truth to Peano Arithmetic we increase its power, so truth has mathematical content! [Horsten] |
| Full Idea: It is surprising that just by adding to Peano Arithmetic principles concerning the notion of truth, we increase the mathematical strength of PA. So, contrary to expectations, the 'philosophical' notion of truth has real mathematical content. | |
| From: Leon Horsten (The Tarskian Turn [2011], 06.4) | |
| A reaction: Horsten invites us to be really boggled by this. All of this is in the Compositional Theory TC. It enables a proof of the consistency of arithmetic (but still won't escape Gödel's Second). |
| 15330 | Friedman-Sheard theory keeps classical logic and aims for maximum strength [Horsten] |
| Full Idea: The Friedman-Sheard theory of truth holds onto classical logic and tries to construct a theory that is as strong as possible. | |
| From: Leon Horsten (The Tarskian Turn [2011], 01.4) |
| 15331 | Kripke-Feferman has truth gaps, instead of classical logic, and aims for maximum strength [Horsten] |
| Full Idea: If we abandon classical logic in favour of truth-value gaps and try to strengthen the theory, this leads to the Kripke-Feferman theory of truth, and variants of it. | |
| From: Leon Horsten (The Tarskian Turn [2011], 01.4) |
| 15325 | Inferential deflationism says truth has no essence because no unrestricted logic governs the concept [Horsten] |
| Full Idea: According to 'inferential deflationism', truth is a concept without a nature or an essence. This is betrayed by the fact that there are no unrestricted logical laws that govern the concept of truth. | |
| From: Leon Horsten (The Tarskian Turn [2011], 01.1) |
| 15344 | Deflationism skips definitions and models, and offers just accounts of basic laws of truth [Horsten] |
| Full Idea: Contemporary deflationism about truth does not attempt to define truth, and does not rely on models containing the truth predicate. Instead they are interpretations of axiomatic theories of truth, containing only basic laws of truth. | |
| From: Leon Horsten (The Tarskian Turn [2011], 02.3) |
| 15356 | Deflationism concerns the nature and role of truth, but not its laws [Horsten] |
| Full Idea: Deflationism is not a theory of the laws of truth. It is a view on the nature and role of the concept of truth. | |
| From: Leon Horsten (The Tarskian Turn [2011], 05 Intro) |
| 15368 | This deflationary account says truth has a role in generality, and in inference [Horsten] |
| Full Idea: On the conception of deflationism developed in this book, the prime positive role of the truth predicate is to serve as a device for expressing generalities, and an inferential tool. | |
| From: Leon Horsten (The Tarskian Turn [2011], 07.5) |
| 15358 | Deflationism says truth isn't a topic on its own - it just concerns what is true [Horsten] |
| Full Idea: Deflationism says the theory of truth does not have a substantial domain of its own. The domain of the theory of truth consists of the bearers of truth. | |
| From: Leon Horsten (The Tarskian Turn [2011], 05.1) | |
| A reaction: The immediate thought is that truth also concerns falsehoods, which would be inexplicable without it. If physics just concerns the physical, does that mean that physics lacks its own 'domain'? Generalising about the truths is a topic. |
| 15359 | Deflation: instead of asserting a sentence, we can treat it as an object with the truth-property [Horsten] |
| Full Idea: The Deflationary view just says that instead of asserting a sentence, we can turn the sentence into an object and assert that this object has the property of truth. | |
| From: Leon Horsten (The Tarskian Turn [2011], 05.2.2) | |
| A reaction: That seems to leave a big question hanging, which concerns the nature of the property that is being attributed to this object. Quine 1970:10-13 says it is just a 'device'. Surely you can rest content with that as an account of truth? |
| 9449 | The plausible Barcan formula implies modality in the actual world [Bird] |
| Full Idea: Modality in the actual world is the import of the Barcan formula, and there are good reasons for accepting the Barcan formula. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 1.2) | |
| A reaction: If you thought logic was irrelevant to metaphysics, this should make you think twice. |
| 15329 | Nonclassical may accept T/F but deny applicability, or it may deny just T or F as well [Horsten] |
| Full Idea: Some nonclassical logic stays close to classical, assuming two mutually exclusive truth values T and F, but some sentences fail to have one. Others have further truth values such as 'half truth', or dialethists allow some T and F at the same time. | |
| From: Leon Horsten (The Tarskian Turn [2011], 01.2) | |
| A reaction: I take that to say that the first lot accept bivalence but reject excluded middle (allowing 'truth value gaps'), while the second lot reject both. Bivalence gives the values available, and excluded middle says what has them. |
| 15326 | Doubt is thrown on classical logic by the way it so easily produces the liar paradox [Horsten] |
| Full Idea: Aside from logic, so little is needed to generate the liar paradox that one wonders whether the laws of classical logic are unrestrictedly valid after all. (Many theories of truth have therefore been formulated in nonclassical logic.) | |
| From: Leon Horsten (The Tarskian Turn [2011], 01.2) | |
| A reaction: Kripke uses Strong Kleene logic for his theory. The implication is that debates discussed by Horsten actually have the status of classical logic at stake, as well as the nature of truth. |
| 15341 | Deduction Theorem: ψ only derivable from φ iff φ→ψ are axioms [Horsten] |
| Full Idea: The Deduction Theorem says ψ is derivable in classical predicate logic from ψ iff the sentence φ→ψ is a theorem of classical logic. Hence inferring φ to ψ is truth-preserving iff the axiom scheme φ→ψ is provable. | |
| From: Leon Horsten (The Tarskian Turn [2011], 02.2) | |
| A reaction: Horsten offers this to show that the Tarski bi-conditionals can themselves be justified, and not just the rule of inference involved. Apparently you can only derive something if you first announce that you have the ability to derive it. Odd. |
| 15328 | A theory is 'non-conservative' if it facilitates new mathematical proofs [Horsten] |
| Full Idea: A theory is 'non-conservative' if it allows us to prove mathematical facts that go beyond what the background mathematical theory can prove on its own. | |
| From: Leon Horsten (The Tarskian Turn [2011], 01.4) | |
| A reaction: This is an instance of the relationship with mathematics being used as the test case for explorations of logic. It is a standard research method, because it is so precise, but should not be mistaken for the last word about a theory. |
| 9868 | An expression refers if it is a singular term in some true sentences [Wright,C, by Dummett] |
| Full Idea: For Wright, an expression refers to an object if it fulfils the 'syntactic role' of a singular term, and if we have fixed the truth-conditions of sentences containing it in such a way that some of them come out true. | |
| From: report of Crispin Wright (Frege's Concept of Numbers as Objects [1983]) by Michael Dummett - Frege philosophy of mathematics Ch.15 | |
| A reaction: Much waffle is written about reference, and it is nice to hear of someone actually trying to state the necessary and sufficient conditions for reference to be successful. So is it possible for 'the round square' to ever refer? '...is impossible to draw' |
| 15349 | It is easier to imagine truth-value gaps (for the Liar, say) than for truth-value gluts (both T and F) [Horsten] |
| Full Idea: It is easier to imagine what it is like for a sentence to lack a truth value than what it is like for a sentence to be both truth and false. So I am grudgingly willing to entertain the possibility that certain sentences (like the Liar) lack a truth value. | |
| From: Leon Horsten (The Tarskian Turn [2011], 02.5) | |
| A reaction: Fans of truth value gluts are dialethists like Graham Priest. I'm with Horsten on this one. But in what way can a sentence be meaningful if it lacks a truth-value? He mentions unfulfilled presuppositions and indicative conditionals as gappy. |
| 15366 | Satisfaction is a primitive notion, and very liable to semantical paradoxes [Horsten] |
| Full Idea: Satisfaction is a more primitive notion than truth, and it is even more susceptible to semantical paradoxes than the truth predicate. | |
| From: Leon Horsten (The Tarskian Turn [2011], 06.3) | |
| A reaction: The Liar is the best known paradox here. Tarski bases his account of truth on this primitive notion, so Horsten is pointing out the difficulties. |
| 10884 | A theory is 'categorical' if it has just one model up to isomorphism [Horsten] |
| Full Idea: If a theory has, up to isomorphism, exactly one model, then it is said to be 'categorical'. | |
| From: Leon Horsten (Philosophy of Mathematics [2007], §5.2) |
| 15353 | The first incompleteness theorem means that consistency does not entail soundness [Horsten] |
| Full Idea: It is a lesson of the first incompleteness theorem that consistency does not entail soundness. If we add the negation of the gödel sentence for PA as an extra axiom to PA, the result is consistent. This negation is false, so the theory is unsound. | |
| From: Leon Horsten (The Tarskian Turn [2011], 04.3) |
| 15355 | Strengthened Liar: 'this sentence is not true in any context' - in no context can this be evaluated [Horsten] |
| Full Idea: The Strengthened Liar sentence says 'this sentence is not true in any context'. It is not hard to figure out that there is no context in which the sentence can be coherently evaluated. | |
| From: Leon Horsten (The Tarskian Turn [2011], 04.6) |
| 13861 | Number theory aims at the essence of natural numbers, giving their nature, and the epistemology [Wright,C] |
| Full Idea: In the Fregean view number theory is a science, aimed at those truths furnished by the essential properties of zero and its successors. The two broad question are then the nature of the objects, and the epistemology of those facts. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], Intro) | |
| A reaction: [compressed] I pounce on the word 'essence' here (my thing). My first question is about the extent to which the natural numbers all have one generic essence, and the extent to which they are individuals (bless their little cotton socks). |
| 13892 | One could grasp numbers, and name sizes with them, without grasping ordering [Wright,C] |
| Full Idea: Someone could be clear about number identities, and distinguish numbers from other things, without conceiving them as ordered in a progression at all. The point of them would be to make comparisons between sizes of groups. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 3.xv) | |
| A reaction: Hm. Could you grasp size if you couldn't grasp which of two groups was the bigger? What's the point of noting that I have ten pounds and you only have five, if you don't realise that I have more than you? You could have called them Caesar and Brutus. |
| 15364 | English expressions are denumerably infinite, but reals are nondenumerable, so many are unnameable [Horsten] |
| Full Idea: The number of English expressions is denumerably infinite. But Cantor's theorem can be used to show that there are nondenumerably many real numbers. So not every real number has a (simple or complex name in English). | |
| From: Leon Horsten (The Tarskian Turn [2011], 06.3) | |
| A reaction: This really bothers me. Are we supposed to be committed to the existence of entities which are beyond our powers of naming? How precise must naming be? If I say 'pick a random real number', might that potentially name all of them? |
| 13867 | Instances of a non-sortal concept can only be counted relative to a sortal concept [Wright,C] |
| Full Idea: The invitation to number the instances of some non-sortal concept is intelligible only if it is relativised to a sortal. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 1.i) | |
| A reaction: I take this to be an essentially Fregean idea, as when we count the boots when we have decided whether they fall under the concept 'boot' or the concept 'pair'. I also take this to be the traditional question 'what units are you using'? |
| 10885 | Computer proofs don't provide explanations [Horsten] |
| Full Idea: Mathematicians are uncomfortable with computerised proofs because a 'good' proof should do more than convince us that a certain statement is true. It should also explain why the statement in question holds. | |
| From: Leon Horsten (Philosophy of Mathematics [2007], §5.3) |
| 17441 | Wright thinks Hume's Principle is more fundamental to cardinals than the Peano Axioms are [Wright,C, by Heck] |
| Full Idea: Wright is claiming that HP is a special sort of truth in some way: it is supposed to be the fundamental truth about cardinality; ...in particular, HP is supposed to be more fundamental, in some sense than the Dedekind-Peano axioms. | |
| From: report of Crispin Wright (Frege's Concept of Numbers as Objects [1983]) by Richard G. Heck - Cardinality, Counting and Equinumerosity 1 | |
| A reaction: Heck notes that although PA can be proved from HP, HP can be proven from PA plus definitions, so direction of proof won't show fundamentality. He adds that Wright thinks HP is 'more illuminating'. |
| 13862 | There are five Peano axioms, which can be expressed informally [Wright,C] |
| Full Idea: Informally, Peano's axioms are: 0 is a number, numbers have a successor, different numbers have different successors, 0 isn't a successor, properties of 0 which carry over to successors are properties of all numbers. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], Intro) | |
| A reaction: Each statement of the famous axioms is slightly different from the others, and I have reworded Wright to fit him in. Since the last one (the 'induction axiom') is about properties, it invites formalization in second-order logic. |
| 17853 | Number truths are said to be the consequence of PA - but it needs semantic consequence [Wright,C] |
| Full Idea: The intuitive proposal is the essential number theoretic truths are precisely the logical consequences of the Peano axioms, ...but the notion of consequence is a semantic one...and it is not obvious that we possess a semantic notion of the requisite kind. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], Intro) | |
| A reaction: (Not sure I understand this, but it is his starting point for rejecting PA as the essence of arithmetic). |
| 17854 | What facts underpin the truths of the Peano axioms? [Wright,C] |
| Full Idea: We incline to think of the Peano axioms as truths of some sort; so there has to be a philosophical question how we ought to conceive of the nature of the facts which make those statements true. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], Intro) | |
| A reaction: [He also asks about how we know the truths] |
| 13894 | Sameness of number is fundamental, not counting, despite children learning that first [Wright,C] |
| Full Idea: We teach our children to count, sometimes with no attempt to explain what the sounds mean. Doubtless it is this habit which makes it so natural to think of the number series as fundamental. Frege's insight is that sameness of number is fundamental. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 3.xv) | |
| A reaction: 'When do children understand number?' rather than when they can recite numerals. I can't make sense of someone being supposed to understand number without a grasp of which numbers are bigger or smaller. To make 13='15' do I add or subtract? |
| 10140 | We derive Hume's Law from Law V, then discard the latter in deriving arithmetic [Wright,C, by Fine,K] |
| Full Idea: Wright says the Fregean arithmetic can be broken down into two steps: first, Hume's Law may be derived from Law V; and then, arithmetic may be derived from Hume's Law without any help from Law V. | |
| From: report of Crispin Wright (Frege's Concept of Numbers as Objects [1983]) by Kit Fine - The Limits of Abstraction I.4 | |
| A reaction: This sounds odd if Law V is false, but presumably Hume's Law ends up as free-standing. It seems doubtful whether the resulting theory would count as logic. |
| 8692 | Frege has a good system if his 'number principle' replaces his basic law V [Wright,C, by Friend] |
| Full Idea: Wright proposed removing Frege's basic law V (which led to paradox), replacing it with Frege's 'number principle' (identity of numbers is one-to-one correspondence). The new system is formally consistent, and the Peano axioms can be derived from it. | |
| From: report of Crispin Wright (Frege's Concept of Numbers as Objects [1983]) by Michèle Friend - Introducing the Philosophy of Mathematics 3.7 | |
| A reaction: The 'number principle' is also called 'Hume's principle'. This idea of Wright's resurrected the project of logicism. The jury is ought again... Frege himself questioned whether the number principle was a part of logic, which would be bad for 'logicism'. |
| 17440 | Wright says Hume's Principle is analytic of cardinal numbers, like a definition [Wright,C, by Heck] |
| Full Idea: Wright intends the claim that Hume's Principle (HP) embodies an explanation of the concept of number to imply that it is analytic of the concept of cardinal number - so it is an analytic or conceptual truth, much as a definition would be. | |
| From: report of Crispin Wright (Frege's Concept of Numbers as Objects [1983]) by Richard G. Heck - Cardinality, Counting and Equinumerosity 1 | |
| A reaction: Boolos is quoted as disagreeing. Wright is claiming a fundamental truth. Boolos says something can fix the character of something (as yellow fixes bananas), but that doesn't make it 'fundamental'. I want to defend 'fundamental'. |
| 13893 | It is 1-1 correlation of concepts, and not progression, which distinguishes natural number [Wright,C] |
| Full Idea: What is fundamental to possession of any notion of natural number at all is not the knowledge that the numbers may be arrayed in a progression but the knowledge that they are identified and distinguished by reference to 1-1 correlation among concepts. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 3.xv) | |
| A reaction: My question is 'what is the essence of number?', and my inclination to disagree with Wright on this point suggests that the essence of number is indeed caught in the Dedekind-Peano axioms. But what of infinite numbers? |
| 13888 | If numbers are extensions, Frege must first solve the Caesar problem for extensions [Wright,C] |
| Full Idea: Identifying numbers with extensions will not solve the Caesar problem for numbers unless we have already solved the Caesar problem for extensions. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 3.xiv) |
| 10881 | The concept of 'ordinal number' is set-theoretic, not arithmetical [Horsten] |
| Full Idea: The notion of an ordinal number is a set-theoretic, and hence non-arithmetical, concept. | |
| From: Leon Horsten (Philosophy of Mathematics [2007], §2.3) |
| 15360 | ZFC showed that the concept of set is mathematical, not logical, because of its existence claims [Horsten] |
| Full Idea: One of the strengths of ZFC is that it shows that the concept of set is a mathematical concept. Many originally took it to be a logical concept. But ZFC makes mind-boggling existence claims, which should not follow if it was a logical concept. | |
| From: Leon Horsten (The Tarskian Turn [2011], 05.2.3) | |
| A reaction: This suggests that set theory is not just a way of expressing mathematics (see Benacerraf 1965), but that some aspect of mathematics has been revealed by it - maybe even its essential nature. |
| 15369 | Set theory is substantial over first-order arithmetic, because it enables new proofs [Horsten] |
| Full Idea: The nonconservativeness of set theory over first-order arithmetic has done much to establish set theory as a substantial theory indeed. | |
| From: Leon Horsten (The Tarskian Turn [2011], 07.5) | |
| A reaction: Horsten goes on to point out the price paid, which is the whole new ontology which has to be added to the arithmetic. Who cares? It's all fictions anyway! |
| 13869 | Number platonism says that natural number is a sortal concept [Wright,C] |
| Full Idea: Number-theoretic platonism is just the thesis that natural number is a sortal concept. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 1.i) | |
| A reaction: See Crispin Wright on sortals to expound this. An odd way to express platonism, but he is presenting the Fregean version of it. |
| 13870 | We can't use empiricism to dismiss numbers, if numbers are our main evidence against empiricism [Wright,C] |
| Full Idea: We may not be able to settle whether some general form of empiricism is correct independently of natural numbers. It might be precisely our grasp of the abstract sortal, natural number, which shows the hypothesis of empiricism to be wrong. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 1.i) | |
| A reaction: A nice turning of the tables. In the end only coherence decides these things. You may accept numbers and reject empiricism, and then find you have opened the floodgates for abstracta. Excessive floodgates, or blockages of healthy streams? |
| 13873 | Treating numbers adjectivally is treating them as quantifiers [Wright,C] |
| Full Idea: Treating numbers adjectivally is, in effect, treating the numbers as quantifiers. Frege observes that we can always parse out any apparently adjectival use of a number word in terms of substantival use. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 1.iii) | |
| A reaction: The immediate response to this is that any substantival use can equally be expressed adjectivally. If you say 'the number of moons of Jupiter is four', I can reply 'oh, you mean Jupiter has four moons'. |
| 13899 | The Peano Axioms, and infinity of cardinal numbers, are logical consequences of how we explain cardinals [Wright,C] |
| Full Idea: The Peano Axioms are logical consequences of a statement constituting the core of an explanation of the notion of cardinal number. The infinity of cardinal numbers emerges as a consequence of the way cardinal number is explained. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 4.xix) | |
| A reaction: This, along with Idea 13896, nicely summarises the neo-logicist project. I tend to favour a strategy which starts from ordering, rather than identities (1-1), but an attraction is that this approach is closer to counting objects in its basics. |
| 13896 | The aim is to follow Frege's strategy to derive the Peano Axioms, but without invoking classes [Wright,C] |
| Full Idea: We shall endeavour to see whether it is possible to follow through the strategy adumbrated in 'Grundlagen' for establishing the Peano Axioms without at any stage invoking classes. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 4.xvi) | |
| A reaction: The key idea of neo-logicism. If you can avoid classes entirely, then set theory paradoxes become irrelevant, and classes aren't logic. Philosophers now try to derive the Peano Axioms from all sorts of things. Wright admits infinity is a problem. |
| 7804 | Wright has revived Frege's discredited logicism [Wright,C, by Benardete,JA] |
| Full Idea: Crispin Wright has reactivated Frege's logistic program, which for decades just about everybody assumed was a lost cause. | |
| From: report of Crispin Wright (Frege's Concept of Numbers as Objects [1983]) by José A. Benardete - Logic and Ontology 3 | |
| A reaction: [This opens Bernadete's section called "Back to Strong Logicism?"] |
| 13863 | Logicism seemed to fail by Russell's paradox, Gödel's theorems, and non-logical axioms [Wright,C] |
| Full Idea: Most would cite Russell's paradox, the non-logical character of the axioms which Russell and Whitehead's reconstruction of Frege's enterprise was constrained to employ, and the incompleteness theorems of Gödel, as decisive for logicism's failure. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], Intro) |
| 13895 | The standard objections are Russell's Paradox, non-logical axioms, and Gödel's theorems [Wright,C] |
| Full Idea: The general view is that Russell's Paradox put paid to Frege's logicist attempt, and Russell's own attempt is vitiated by the non-logical character of his axioms (esp. Infinity), and by the incompleteness theorems of Gödel. But these are bad reasons. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 4.xvi) | |
| A reaction: Wright's work is the famous modern attempt to reestablish logicism, in the face of these objections. |
| 15370 | Predicativism says mathematical definitions must not include the thing being defined [Horsten] |
| Full Idea: Predicativism has it that a mathematical object (such as a set of numbers) cannot be defined by quantifying over a collection that includes that same mathematical object. To do so would be a violation of the vicious circle principle. | |
| From: Leon Horsten (The Tarskian Turn [2011], 07.7) | |
| A reaction: In other words, when you define an object you are obliged to predicate something new, and not just recycle the stuff you already have. |
| 13884 | The idea that 'exist' has multiple senses is not coherent [Wright,C] |
| Full Idea: I have the gravest doubts whether any coherent account could be given of any multiplicity of senses of 'exist'. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 2.x) | |
| A reaction: I thoroughly agree with this thought. Do water and wind exist in different senses of 'exist'? |
| 9501 | If all existents are causally active, that excludes abstracta and causally isolated objects [Bird] |
| Full Idea: If one says that 'everything that exists is causally active', that rules out abstracta (notably sets and numbers), and it rules out objects that are causally isolated. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 5.5) | |
| A reaction: I like the principle. I take abstracta to be brain events, so they are causally active, within highly refined and focused brains, and if your physics is built on the notion of fields then I would think a 'causally isolated' object incoherent. |
| 9500 | If naturalism refers to supervenience, that leaves necessary entities untouched [Bird] |
| Full Idea: If one's naturalistic principles are formulated in terms of supervenience, then necessary entities are left untouched. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 5.5) | |
| A reaction: I take this to be part of the reason why some people like supervenience - that it leaves a pure 'space of reasons' which is unreachable from the flesh and blood inside a cranium. Personall I like the space of reasons, but I drop the 'pure'. |
| 6780 | Anti-realism is more plausible about laws than about entities and theories [Bird] |
| Full Idea: There is anti-realism with regard to unobservable entities and the theories that purport to mention them, but the more plausible version attaches to theories concerning what laws of nature are. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.4) | |
| A reaction: This sounds right. I certainly find anti-realism about the entities of science utterly implausible. I also doubt whether there is any such thing as a law, above and beyond the behaviour of matter. Theories float between the two. |
| 15338 | We may believe in atomic facts, but surely not complex disjunctive ones? [Horsten] |
| Full Idea: While positive and perhaps even negative atomic facts may be unproblematic, it seems excessive to commit oneself to the existence of logically complex facts such as disjunctive facts. | |
| From: Leon Horsten (The Tarskian Turn [2011], 02.1) | |
| A reaction: Presumably it is hard to deny that very complex statements involving massive disjunctions can be true or false. But why does commitment to real facts have to involve a huge ontology? The ontology is just the ingredients of the fact, isn't it? |
| 15363 | In the supervaluationist account, disjunctions are not determined by their disjuncts [Horsten] |
| Full Idea: If 'Britain is large' and 'Italy is large' lack truth values, then so must 'Britain or Italy is large' - so on the supervaluationist account the truth value of a disjunction is not determined by the truth values of its disjuncts. | |
| From: Leon Horsten (The Tarskian Turn [2011], 06.2) | |
| A reaction: Compare Idea 15362 to get the full picture here. |
| 15362 | If 'Italy is large' lacks truth, so must 'Italy is not large'; but classical logic says it's large or it isn't [Horsten] |
| Full Idea: If 'Italy is a large country' lacks a truth value, then so too, presumably, does 'Italy is not a large country'. But 'Italy is or is not a large country' is true, on the supervaluationist account, because it is a truth of classical propositional logic. | |
| From: Leon Horsten (The Tarskian Turn [2011], 06.2) | |
| A reaction: See also Idea 15363. He cites Fine 1975. |
| 13877 | Singular terms in true sentences must refer to objects; there is no further question about their existence [Wright,C] |
| Full Idea: When a class of terms functions as singular terms, and the sentences are true, then those terms genuinely refer. Being singular terms, their reference is to objects. There is no further question whether they really refer, and there are such objects. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 1.iii) | |
| A reaction: This seems to be a key sentence, because this whole view is standardly called 'platonic', but it certainly isn't platonism as we know it, Jim. Ontology has become an entirely linguistic matter, but do we then have 'sakes' and 'whereaboutses'? |
| 9502 | There might be just one fundamental natural property [Bird] |
| Full Idea: The thought that there might be just one fundamental natural property is not that strange. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 6.3) | |
| A reaction: A nice variation on the Parmenides idea that only the One exists. Bird's point would refer to a possible unification of modern physics. We see, for example, the forces of electricity and of magnetism turning out to be the same force. |
| 9477 | Categorical properties are not modally fixed, but change across possible worlds [Bird] |
| Full Idea: Categorical properties do not have their dispositional characters modally fixed, but may change their dispositional characters (and their causal and nomic behaviour more generally) across different worlds. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 3.1) | |
| A reaction: This is the key ground for Bird's praiseworth opposition to categorical propertie. I take it to be a nonsense to call the category in which we place something a 'property' of that thing. A confusion of thought with reality. |
| 9490 | The categoricalist idea is that a property is only individuated by being itself [Bird] |
| Full Idea: In the categoricalist view, the essential properties of a natural property are limited to its essentially being itself and not some distinct property. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 4.1) | |
| A reaction: He associates this view with Lewis (modern regularity view) and Armstrong (nomic necessitation), and launches a splendid attack against it. I have always laughed at the idea that 'being Socrates' was one of the properties of Socrates. |
| 9495 | If we abstractly define a property, that doesn't mean some object could possess it [Bird] |
| Full Idea: The possibility of abstract definition does not show that we have defined a property that we can know, independently of any theory, that it is physically possible for some object to possess. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 4.2.3.1) | |
| A reaction: This is a naturalist resisting the idea that there is no more to a property than set-membership. I strongly agree. We need a firm notion of properties as features of the actual world; anything else should be called something like 'categorisations'. |
| 9492 | Categoricalists take properties to be quiddities, with no essential difference between them [Bird] |
| Full Idea: The categoricalist conception of properties takes them to be quiddities, which are primitive identities between fundamental qualities, having no difference with regard to their essence. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 4.5) | |
| A reaction: Compare 'haecceitism' about indentity of objects, though 'quidditism' sounds even less plausible. Bird attributes this view to Lewis and Armstrong, and makes it sound well daft. |
| 9503 | To name an abundant property is either a Fregean concept, or a simple predicate [Bird] |
| Full Idea: It isn't clear what it is to name an abundant property. One might reify them, as akin to Fregean concepts, or it might be equivalent to a simple predication. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 7.1.2) | |
| A reaction: 'Fregean concepts' would make them functions that purely link things (hence relational?). One suspects that people who actually treat abundant properties as part of their ontology (Lewis) are confusing natural properties with predicates. |
| 14540 | Only real powers are fundamental [Bird, by Mumford/Anjum] |
| Full Idea: Bird says only real powers are fundamental. | |
| From: report of Alexander Bird (Nature's Metaphysics [2007]) by S.Mumford/R.Lill Anjum - Getting Causes from Powers 1.5 | |
| A reaction: They disagree, and want higher-level properties in their ontology. I'm with Bird, except that something must exist to have the powers. Powers are fundamental to all the activity of nature, and are intrinsic to the stuff which constitutes nature. |
| 9450 | If all properties are potencies, and stimuli and manifestation characterise them, there is a regress [Bird] |
| Full Idea: Potencies are characterized in terms of their stimulus and manifestation properties, then if potencies are the only properties then these properties are also potencies, and must be characterized by yet further properties, leading to a vicious regress. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 1.2) | |
| A reaction: This is cited as the most popular objection to the dispositional account of properties. |
| 9498 | The essence of a potency involves relations, e.g. mass, to impressed force and acceleration [Bird] |
| Full Idea: The essence of a potency involves a relation to something else; if inertial mass is a potency then its essence involves a relation to a stimulus property (impressed force) and a manifestation property (acceleration). | |
| From: Alexander Bird (Nature's Metaphysics [2007], 5.3.3) | |
| A reaction: It doesn't seem quite right to say that the relations are part of the essence, if they might not occur, but some other relations might happen in their place. An essence is what makes a relation possible (like being good-looking). |
| 9474 | A disposition is finkish if a time delay might mean the manifestation fizzles out [Bird] |
| Full Idea: Finkish dispositions arise because the time delay between stimulus and manifestation provides an opportunity for the disposition to go out of existence and so halt the process that would bring about the manifestation. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 2.2.3) | |
| A reaction: This is a problem for the conditional analysis of dispositions; there may be a disposition, but it never reaches manifestation. Bird rightly points us towards actual powers rather than dispositions that need manifestation. |
| 9475 | A robust pot attached to a sensitive bomb is not fragile, but if struck it will easily break [Bird] |
| Full Idea: If a robust iron pot is attached to a bomb with a sensitive detonator. If the pot is struck, the bomb will go off, so they counterfactual 'if the pot were struck it would break' is true, but it is not a fragile pot. This is a 'mimic' of the disposition. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 2.2.5.1) | |
| A reaction: A very nice example, showing that a true disposition would have to be an internal feature (a power) of the pot itself, not a mere disposition to behave. The problem is these pesky empiricists, who want to reduce it all to what is observable. |
| 9499 | Megarian actualists deny unmanifested dispositions [Bird] |
| Full Idea: The Megarian actualist denies that a disposition can exist without being manifested. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 5.4) | |
| A reaction: I agree with Bird that this extreme realism seems wrong. As he puts it (p.109), "unrealized possibilities must be part of the actual world". This commitment is beginning to change my understanding of the world I am looking at. |
| 9486 | Why should a universal's existence depend on instantiation in an existing particular? [Bird] |
| Full Idea: An instantiation condition seems to be a failure of nerve as regards realism about universals. If universals really are entities in their own right, why should their existence depend upon a relationship with existing particulars? | |
| From: Alexander Bird (Nature's Metaphysics [2007], 3.2.2) | |
| A reaction: I like this challenge, which seems to leave fans of universals no option but full-blown Platonism, which most of them recognise as being deeply implausible. |
| 9472 | Resemblance itself needs explanation, presumably in terms of something held in common [Bird] |
| Full Idea: The realist view of resemblance nominalism is that it is resemblance that needs explaining. When there is resemblance it is natural to want to explain it, in terms of something held in common. Explanations end somewhere, but not with resemblance. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 2.1.2) | |
| A reaction: I smell a regress. If a knife and a razor resemble because they share sharpness, you have to see that the sharp phenomenon falls within the category of 'sharpness' before you can make the connection, which is spotting its similarity. |
| 9878 | Contextually defined abstract terms genuinely refer to objects [Wright,C, by Dummett] |
| Full Idea: Wright says we should accord to contextually defined abstract terms a genuine full-blown reference to objects. | |
| From: report of Crispin Wright (Frege's Concept of Numbers as Objects [1983]) by Michael Dummett - Frege philosophy of mathematics Ch.18 | |
| A reaction: This is the punch line of Wright's neo-logicist programme. See Idea 9868 for his view of reference. Dummett regards this strong view of contextual definition as 'exorbitant'. Wright's view strikes me as blatantly false. |
| 13868 | Sortal concepts cannot require that things don't survive their loss, because of phase sortals [Wright,C] |
| Full Idea: The claim that no concept counts as sortal if an instance of it can survive its loss, runs foul of so-called phase sortals like 'embryo' and 'chrysalis'. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 1.i) | |
| A reaction: The point being that those items only fall under that sortal for one phase of their career, and of their identity. I've always thought such claims absurd, and this gives a good reason for my view. |
| 9482 | If the laws necessarily imply p, that doesn't give a new 'nomological' necessity [Bird] |
| Full Idea: It does not add to the kinds of necessity to say that p is 'nomologically necessary' iff (the laws of nature → p) is metaphysically necessary. That trick of construction could be pulled for 'feline necessity' (true in all worlds that contain cats). | |
| From: Alexander Bird (Nature's Metaphysics [2007], 3.1.2) | |
| A reaction: I love it! Bird seems to think that the only necessity is 'metaphysical' necessity, true in all possible worlds, and he is right. The question arises in modal logic, though, of the accessibility between worlds (which might give degrees of necessity?). |
| 12189 | Logical necessity involves a decision about usage, and is non-realist and non-cognitive [Wright,C, by McFetridge] |
| Full Idea: Wright espouses a non-realist, indeed non-cognitive account of logical necessity. Crucial to this is the idea that acceptance of a statement as necessary always involves an element of decision (to use it in a necessary way). | |
| From: report of Crispin Wright (Inventing Logical Necessity [1986]) by Ian McFetridge - Logical Necessity: Some Issues §3 | |
| A reaction: This has little appeal to me, as I take (unfashionably) the view that that logical necessity is rooted in the behaviour of the actual physical world, with which you can't argue. We test simple logic by making up examples. |
| 9481 | Logical necessitation is not a kind of necessity; George Orwell not being Eric Blair is not a real possibility [Bird] |
| Full Idea: I do not regard logical necessitation as a kind of necessity. It is logically possible that George Orwell is not Eric Blair, but in what sense is this any kind of possibility? It arises from having two names, but that confers no genuine possibility. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 3.1.2) | |
| A reaction: How refreshing. All kinds of concepts like this are just accepted by philosophers as obvious, until someone challenges them. The whole undergrowth of modal thinking needs a good flamethrower taken to it. |
| 6796 | Subjective probability measures personal beliefs; objective probability measures the chance of an event happening [Bird] |
| Full Idea: Subjective probability measures a person's strength of belief in the truth of a proposition; objective probability concerns the chance a certain sort of event has of happening, independently of whether anyone thinks it is likely to occur or not. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.6) | |
| A reaction: The challenge to the second one is that God would know for certain whether a meteor will hit the Earth next week. The impact looks like 'bad luck' to us, but necessary to one who really knows. |
| 6797 | Objective probability of tails measures the bias of the coin, not our beliefs about it [Bird] |
| Full Idea: In tossing a coin, the objective probability of tails is a measure of the bias of the coin; the bias and the probability are objective features of the coin, like its mass and shape; these properties have nothing to do with our beliefs about the coin. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.6) | |
| A reaction: Despite my reservation that God would not seem to be very interested in the probabilities of coin-tossing, since he knows each outcome with certaintly, this is fairly convincing. God might say that the coin has a 'three-to-two bias'. |
| 9505 | Empiricist saw imaginability and possibility as close, but now they seem remote [Bird] |
| Full Idea: Whereas the link between imaginability and possibility was once held, under the influence of empiricism, to be close, it is now widely held to be very remote. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 8) | |
| A reaction: Tim Williamson nicely argues the opposite - that assessment of possibility is an adjunct of our ability to think counterfactually, which is precisely an operation of the imagination. Big error is possible, but how else could we do it? |
| 9491 | Haecceitism says identity is independent of qualities and without essence [Bird] |
| Full Idea: The core of haecceitism is the view that the transworld identity of particulars does not supervene on their qualitative features. ...The simplest expression of it is that particulars lack essential properties. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 4.2.1) | |
| A reaction: This seems to be something the 'bare substratum' account of substance (associated with Locke). You are left with the difficulty of how to individuate an instance of the haecceity, as opposed to the bundle of properties attached to it. |
| 15372 | Some claim that indicative conditionals are believed by people, even though they are not actually held true [Horsten] |
| Full Idea: In the debate about doxastic attitudes towards indicative conditional sentences, one finds philosophers who claim that conditionals can be believed even though they have no truth value (and thus are not true). | |
| From: Leon Horsten (The Tarskian Turn [2011], 09.3) |
| 6800 | Many philosophers rate justification as a more important concept than knowledge [Bird] |
| Full Idea: Many philosophers take the notion of justification to be more important or more basic than the concept of knowledge. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.7) | |
| A reaction: Intriguing. Given the obvious social and conventional element in 'knowledge' ("do we agree that the candidate really knows the answer?"), justification may well be closer to where the real action is. 'Logos', after all, is at the heart of philosophy. |
| 6786 | As science investigates more phenomena, the theories it needs decreases [Bird] |
| Full Idea: A remarkable fact about modern science is that as the number of phenomena which science has investigated has grown, the number of theories needed to explain them has decreased. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.4) | |
| A reaction: This rebuts the idea that theories are probably false because we are unlikely to have thought of the right one (Idea 6784). More data suggests more theories, yet we end up with fewer theories. Why is simplification of theories possible? |
| 6792 | If theories need observation, and observations need theories, how do we start? [Bird] |
| Full Idea: If we cannot know the truth of theories without observation, and we cannot know the truth of observations without theories, where do we start? | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.5) | |
| A reaction: See Idea 6793. You make a few observations, under the illusion that they are objective, then formulate a promising theory, then go back and deconstruct the observations, then tighten up the theory, and so on. |
| 6757 | Explanation predicts after the event; prediction explains before the event [Bird] |
| Full Idea: Explanation is prediction after the event and prediction is explanation before the event. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: A nice slogan, fitting Hempel's 'covering law' view of explanation. It doesn't seem quite right, because explanations and predictions are couched in very different language. Prediction implies an explanation; explanation implies a prediction. |
| 6777 | Realists say their theories involve truth and the existence of their phenomena [Bird] |
| Full Idea: A realist says of their theories that they can be evaluated according to truth, they aim at truth, their success favours their truth, their unobserved entities probably exist, and they would explain the observable phenomena. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.4) | |
| A reaction: This seems to me to be the only sensible attitude towards scientific theories, even if they do become confusing down at the level of quantum theory. Theories aim to be true explanations. |
| 6804 | There is no agreement on scientific method - because there is no such thing [Bird] |
| Full Idea: I find little concurrence as to what scientific method might actually be - the reason being, I conclude, that there is no such thing. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.8) | |
| A reaction: I take the essence of science to be two things: first, becoming very fussy about empirical evidence; second, setting up controlled conditions to get at the evidence that seems to be needed. I agree that there seems to be no distinctive way of thinking. |
| 6805 | Relativity ousted Newtonian mechanics despite a loss of simplicity [Bird] |
| Full Idea: The theories of relativity ousted Newtonian mechanics despite a loss of simplicity. | |
| From: Alexander Bird (Philosophy of Science [1998]) | |
| A reaction: This nicely demonstrates that simplicity is not essential, even if it is desirable. The point applies to the use of Ockham's Razor (Idea 6806), and to Hume's objection to miracles (Idea 2227), where strange unnatural events may be the truth. |
| 6778 | Instrumentalists regard theories as tools for prediction, with truth being irrelevant [Bird] |
| Full Idea: Instrumentalism is so called because it regards theories not as attempts to describe or explain the world, but as instruments for making predictions; for the instrumentalist, asking about the truth of a theory is a conceptual mistake. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.4) | |
| A reaction: It cannot be denied that theories are used to make predictions, and there is nothing wrong with being solely interested in predictions. I cannot make head or tail of the idea that truth is irrelevant. Why is a given theory so successful? |
| 6775 | Induction is inference to the best explanation, where the explanation is a law [Bird] |
| Full Idea: Induction can be seen as inference to the best explanation, where the explanation is a law. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: I like this. I increasingly think of explanation as central to rational thought, as the key route for empiricists to go beyond their immediate and verifiable experience. Laws can be probabilistic. |
| 6791 | If Hume is right about induction, there is no scientific knowledge [Bird] |
| Full Idea: If Hume is right about induction then there is no scientific knowledge. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.5) | |
| A reaction: The first step is to recognise that induction is not deductively valid, but that does not make it irrational. If something happens five times, get ready for the sixth. If we discover the necessary features of nature, we can predict the future. |
| 6790 | Anything justifying inferences from observed to unobserved must itself do that [Bird] |
| Full Idea: Whatever could do the job of justifying an inference from the observed to the unobserved must itself be an inference from the observed to the unobserved. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.5) | |
| A reaction: We must first accept that the unobserved might not be like the observed, no matter how much regularity we have, so it can't possibly be a logical 'inference'. Essences generate regularities, but non-essences may not. |
| 6738 | Any conclusion can be drawn from an induction, if we use grue-like predicates [Bird] |
| Full Idea: It looks as if any claim about the future can be made to be a conclusion of an inductive argument from any premises about the past, as long as we use a strange enough grue-like predicate. | |
| From: Alexander Bird (Philosophy of Science [1998], Intro) | |
| A reaction: So don't use strange grue-like predicates. If all our predicates randomly changed their reference each day, we would be unable to talk to one another at all. Emeralds don't change their colour-properties, so why change the predicates that refer to them? |
| 6739 | Several months of observing beech trees supports the deciduous and evergreen hypotheses [Bird] |
| Full Idea: If someone were to observe beech trees every day over one summer they would have evidence that seems to support both the hypothesis that beech trees are deciduous and the hypothesis that they are evergreens. | |
| From: Alexander Bird (Philosophy of Science [1998], Intro) | |
| A reaction: Bird offers this to anyone who (like me) is tempted to dismiss the 'grue' problem as ridiculous. Obviously he is right; 'deciduous' works like 'grue'. But we invented the predicate 'deciduous' to match an observed property. |
| 6799 | We normally learn natural kinds from laws, but Goodman shows laws require prior natural kinds [Bird] |
| Full Idea: We know what natural kinds there are by seeing which properties appear in the laws of nature. But one lesson of Goodman's problem is that we cannot identify the laws of nature without some prior identification of natural kinds. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.7) | |
| A reaction: For Goodman's problem, see Idea 4783. The essentialist view is that the natural kinds come first, and the so-called 'laws' are just regularities in events that arise from the interaction of stable natural kinds. (Keep predicates and properties separate). |
| 6798 | Bayesianism claims to find rationality and truth in induction, and show how science works [Bird] |
| Full Idea: Keen supporters of Bayesianism say it can show how induction is rational and can lead to truth, and it can reveal the underlying structure of actual scientific reasoning. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.6) | |
| A reaction: See Idea 2798 for Bayes' Theorem. I find it intuitively implausible that our feeling for probabilities could be reduced to precise numbers, given the subjective nature of the numbers we put into the equation. |
| 6752 | The objective component of explanations is the things that must exist for the explanation [Bird] |
| Full Idea: There is an 'objective', non-epistemic component to explanations, consisting of the things that must exist for A to be able to explain B, and the relations those things have to one another. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: There seems to be some question-begging here, in that you have to decide what explanation you are after before you can decide which existences are of interest. There are objective facts, though, about what causally links to what. |
| 6754 | We talk both of 'people' explaining things, and of 'facts' explaining things [Bird] |
| Full Idea: We talk both of 'people' explaining things, and of 'facts' explaining things. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: An important point, and it is the job of philosophers to pull the two apart. How we talk does not necessarily show how it is. The concept of explanation is irrelevant in a universe containing no minds, or one containing only God. People seek the facts. |
| 9487 | We can't reject all explanations because of a regress; inexplicable A can still explain B [Bird] |
| Full Idea: Some regard the potential regress of explanations as a reason to think that the very idea of explanation is illusory. This is a fallacy; it is not a necessary condition on A's explaining B that we have an explanation for A also. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 3.2.4) | |
| A reaction: True, though to say 'B is explained by A, but A is totally baffling' is not the account we are dreaming of. And the explanation would certainly fail if we could say nothing at all about A, apart from naming it. |
| 6750 | Explanations are causal, nomic, psychological, psychoanalytic, Darwinian or functional [Bird] |
| Full Idea: Explanations can be classified as causal, nomic, psychological, psychoanalytic, Darwinian and functional. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: These could be subdivided, perhaps according to different types of cause. Personally, being a reductionist (like David Lewis, see Idea 3989), I suspect that all of these explanations could be reduced to causation. Essences explain causes. |
| 6761 | Contrastive explanations say why one thing happened but not another [Bird] |
| Full Idea: A 'contrastive explanation' explains why one thing happened but not another. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: If I explain why the ship sank, is this contrastive, or just causal, or both? Am I explaining why it sank rather than turned into a giraffe? An interesting concept, but I can't see myself making use of it. |
| 6758 | 'Covering law' explanations only work if no other explanations are to be found [Bird] |
| Full Idea: The fact that something fits the 'covering law' model of explanation is no guarantee that it is an explanation, for that depends on what other explanations are there to be found. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: He gives Achinstein's example of a poisoned man who is run over by a bus. It has to be a basic requirement of explanations that they are the 'best', and not just something that fits a formula. |
| 6759 | Livers always accompany hearts, but they don't explain hearts [Bird] |
| Full Idea: All animals with a liver also have a heart; so we can deduce from this plus the existence of Fido's liver that he also has a heart, but his liver does not explain why he has a heart. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: This is a counterexample to Hempel's deductive-nomological view of explanation. It seems a fairly decisive refutation of any attempt to give a simple rule for explaining things. Different types of explanation compete, and there is a subjective element. |
| 6756 | Probabilistic-statistical explanations don't entail the explanandum, but makes it more likely [Bird] |
| Full Idea: The probabilistic-statistical view of explanation (also called inductive-statistical explantion) is similar to deductive-nomological explanation, but instead of entailing the explanandum a probabilistic-statistical explantion makes it very likely. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: If people have umbrellas up, does that explain rain? Does the presence of a psychopath in the audience explain why I don't go to a rock concert? Still, it has a point. |
| 6760 | An operation might reduce the probability of death, yet explain a death [Bird] |
| Full Idea: An operation for cancer might lead to a patient's death, and so it explains the patient's death while at the same time reducing the probability of death. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: This attacks Hempel's 'covering law' approach. Increasing probability of something clearly does not necessarily explain it, though it often will. Feeding you contaminated food will increase the probability of your death, and may cause it. |
| 6785 | Inference to the Best Explanation is done with facts, so it has to be realist [Bird] |
| Full Idea: Explanation of a fact is some other fact or set of facts. And so Inference to the Best Explanation is inference to facts; someone who employs it cannot but take a realist attitude to a theory which is preferred on these grounds. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.4) | |
| A reaction: So my personal commitment to abduction is entailed by my realism, and my realism is entailed by my belief in the possibility of abduction. We can't explain the properties of a table just by referring to our experiences of tables. |
| 6788 | Maybe bad explanations are the true ones, in this messy world [Bird] |
| Full Idea: It is objected to 'best explanation' that this may well not be the best of all possible worlds - so why think that the best explanation is true? Maybe bad (complicated, unsystematic and weak) explanations are true. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.4) | |
| A reaction: The only rebuttal of this objection to best explanation seems to be a priori. It would just seem an odd situation if very simple explanations fitted the facts and yet were false, like the points on a graph being a straight line by pure coincidence. |
| 6787 | Which explanation is 'best' is bound to be subjective, and no guide to truth [Bird] |
| Full Idea: It is objected to 'best explanation' that beauty is in the eye of the beholder - the goodness of possible explanations is subjective, and so the choice of best explanation is also subjective, and hence not a suitable guide to truth. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.4) | |
| A reaction: Explanation is indeed dependent both on the knowledge of the person involved, and on their interests. That doesn't, though, mean that you can choose any old explanation. Causal networks are features of the world. |
| 6751 | Maybe explanation is so subjective that it cannot be a part of science [Bird] |
| Full Idea: Some philosophers have thought that explanation is hopelessly subjective, so subjective even that it is should have no part in proper science. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: God requires no explanations, and children require many. If fundamental explanations are causal, then laying bare the causal chains is the explanation, whether you want it or not. God knows all the explanations. See Idea 6752. |
| 17527 | Causation seems to be an innate concept (or acquired very early) [Bird] |
| Full Idea: There is evidence that the concept of causation is innate, or that we are primed to acquire it very early in life, within months at most. | |
| From: Alexander Bird (Causation and the Manifestation of Powers [2010], p.167) | |
| A reaction: Bird doesn't give any references. This is important for our understanding of induction. Creatures seem to learn from a single instance, rather than waiting for habit to be ingrained by many instances. They must infer a cause. |
| 13866 | A concept is only a sortal if it gives genuine identity [Wright,C] |
| Full Idea: Before we can conclude that φ expresses a sortal concept, we need to ensure that 'is the same φ as' generates statements of genuine identity rather than of some other equivalence relation. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 1.i) |
| 13865 | 'Sortal' concepts show kinds, use indefinite articles, and require grasping identities [Wright,C] |
| Full Idea: A concept is 'sortal' if it exemplifies a kind of object. ..In English predication of a sortal concept needs an indefinite article ('an' elm). ..What really constitutes the distinction is that it involves grasping identity for things which fall under it. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 1.i) | |
| A reaction: This is a key notion, which underlies the claims of 'sortal essentialism' (see David Wiggins). |
| 13890 | Entities fall under a sortal concept if they can be used to explain identity statements concerning them [Wright,C] |
| Full Idea: 'Tree' is not a sortal concept under which directions fall since we cannot adequately explain the truth-conditions of any identity statement involving a pair of tree-denoting singular terms by appealing to facts to do with parallelism between lines. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 3.xiv) | |
| A reaction: The idea seems to be that these two fall under 'hedgehog', because that is a respect in which they are identical. I like to notion of explanation as a part of this. |
| 13898 | If we can establish directions from lines and parallelism, we were already committed to directions [Wright,C] |
| Full Idea: The fact that it seems possible to establish a sortal notion of direction by reference to lines and parallelism, discloses tacit commitments to directions in statements about parallelism...There is incoherence in the idea that a line might lack direction. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 4.xviii) | |
| A reaction: This seems like a slippery slope into a very extravagant platonism about concepts. Are concepts like direction as much a part of the natural world as rivers are? What other undiscovered concepts await us? |
| 13882 | A milder claim is that understanding requires some evidence of that understanding [Wright,C] |
| Full Idea: A mild version of the verification principle would say that it makes sense to think of someone as understanding an expression only if he is able, by his use of the expression, to give the best possible evidence that he understands it. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 1.vii) | |
| A reaction: That doesn't seem to tell us what understanding actually consists of, and may just be the truism that to demonstrate anything whatsoever will necessarily involve some evidence. |
| 7320 | Holism cannot give a coherent account of scientific methodology [Wright,C, by Miller,A] |
| Full Idea: Crispin Wright has argued that Quine's holism is implausible because it is actually incoherent: he claims that Quine's holism cannot provide us with a coherent account of scientific methodology. | |
| From: report of Crispin Wright (Inventing Logical Necessity [1986]) by Alexander Miller - Philosophy of Language 4.5 | |
| A reaction: This sounds promising, given my intuitive aversion to linguistic holism, and almost everything to do with Quine. Scientific methodology is not isolated, but spreads into our ordinary (experimental) interactions with the world (e.g. Idea 2461). |
| 13885 | If apparent reference can mislead, then so can apparent lack of reference [Wright,C] |
| Full Idea: If the appearance of reference can be misleading, why cannot an apparent lack of reference be misleading? | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 2.xi) | |
| A reaction: A nice simple thought. Analytic philosophy has concerned itself a lot with sentences that seem to refer, but the reference can be analysed away. For me, this takes the question of reference out of the linguistic sphere, which wasn't Wright's plan. |
| 15347 | A theory of syntax can be based on Peano arithmetic, thanks to the translation by Gödel coding [Horsten] |
| Full Idea: A notion of formal provability can be articulated in Peano arithmetic. ..This is surprisingly 'linguistic' rather than mathematical, but the key is in the Gödel coding. ..Hence we use Peano arithmetic as a theory of syntax. | |
| From: Leon Horsten (The Tarskian Turn [2011], 02.4) | |
| A reaction: This is the explanation of why issues in formal semantics end up being studied in systems based on formal arithmetic. And I had thought it was just because they were geeks who dream in numbers, and can't speak language properly... |
| 17857 | We can accept Frege's idea of object without assuming that predicates have a reference [Wright,C] |
| Full Idea: The heart of the problem is Frege's assumption that predicates have Bedeutungen at all; and no reason is at present evident why someone who espouses Frege's notion of object is contrained to make that assumption. | |
| From: Crispin Wright (Frege's Concept of Numbers as Objects [1983], 1.iv) | |
| A reaction: This seems like a penetrating objection to Frege's view of reference, and presumably supports the Kripke approach. |
| 6776 | Natural kinds are those that we use in induction [Bird] |
| Full Idea: Natural kinds are the kinds one should make use of in inductive inference (if that is explanation which leads to laws). | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: The problem with this is that it is epistemological rather than ontological. In induction we use superficial resemblences that are immediately obvious, whereas the nature of kinds can be buried deep in the chemistry or physics. |
| 6767 | Rubies and sapphires are both corundum, with traces of metals varying their colours [Bird] |
| Full Idea: Both rubies (valuable) and sapphires (less valuable) are corundum (Al2O3), differing only in their colours, for which traces of iron, titanium and chomium are responsible. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: A nice example which illustrates how natural kinds determined by nominal essence could be drastically different from those suggested by real essence. It certainly suggests that corundum might be a natural kind, but ruby isn't. |
| 6768 | Tin is not one natural kind, but appears to be 21, depending on isotope [Bird] |
| Full Idea: If real essences are decided by microstructure, then what we call the element tin is not a natural kind, but a mixture of 21 different kinds, one for each isotope. There also exist two different allotropes of tin - white tin and grey tin. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: This example vividly brings out the difficulties of the Kripke-Putnam view. If natural kinds 'overlap', then there would be a very extensive overlap among the 21 isotopes of tin. |
| 6770 | Membership of a purely random collection cannot be used as an explanation [Bird] |
| Full Idea: One might randomly collect diverse things and give the collection a name, but one would not expect it to explain anything to say that a certain object belonged to this collection. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: This is in support of Bird's view that natural kinds are formulated because of their explanatory role. There is, though, an undeniable subjective aspect to explanation, in that explanations arise from the ignorance and interests of persons. |
| 6771 | Natural kinds may overlap, or be sub-kinds of one another [Bird] |
| Full Idea: It seems clear that in some cases one natural kind may be a subkind of another, while in other cases natural kinds may overlap without one being the subkind of another. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: Given the enormous difficulty of pinpointing natural kinds (e.g. Idea 6768), it is hard to know whether the comment is correct or not. Ellis says natural kinds come 'in hierarchies', which would make subkinds normal, but overlapping unlikely. |
| 6773 | If F is a universal appearing in a natural law, then Fs form a natural kind [Bird] |
| Full Idea: The proposal is that if F is a universal appearing in some natural law, then Fs form a natural kind. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: Such proposals always invite the question 'What is it about F that enables it to be a universal in a natural law?' Nothing can be ultimately defined simply by its role. The character (essence, even) of the thing makes the role possible. |
| 6769 | In the Kripke-Putnam view only nuclear physicists can know natural kinds [Bird] |
| Full Idea: In the Kripke-Putnam view, it is very difficult for anyone except nuclear physicists to pick out natural kinds, since everything else is made out of compounds of different isotopes. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: The concept of a rigid 'natural kind' does not have to be sacred. Tin might be considered a natural kind, despite having 21 isotopes. What matters is protons, not the neutrons. |
| 6774 | Darwinism suggests that we should have a native ability to detect natural kinds [Bird] |
| Full Idea: Creatures that are able to recognise natural kinds and laws have a selective advantage, so Darwinism suggests that we should have some native ability to detect natural kinds. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: This seems right, but it makes 'natural kind' a rather instrumental concept, relative to our interests. True natural kinds cut across our interests, as when we discover by anatomy that whales are not fish, or that rubies and sapphires are both corundum. |
| 6764 | Nominal essence of a natural kind is the features that make it fit its name [Bird] |
| Full Idea: The nominal essence of a natural kind K consists of those features a thing must have to deserve the name 'a K' by virtue of the meaning of that name. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: Some people think 'nominal essence' is the only essence there is, which would make it relative to human languages. The rival view is that there are 'real essences'. I favour the latter view. |
| 6766 | Jadeite and nephrite are superficially identical, but have different composition [Bird] |
| Full Idea: There might be more than one natural kind that shares the same superficial features, …jade, for example, has two forms, jadeite and nephrite, which are similar in superficial properties, but have different chemical composition and structure. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: It might be questioned whether jadeite and nephrite really are natural kinds, either together or separately. |
| 6808 | Reference to scientific terms is by explanatory role, not by descriptions [Bird] |
| Full Idea: I propose that reference to scientific terms, such as natural kinds and theoretical terms, is not determined by a sense or description attached to the term, but by its explanatory role. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.8) | |
| A reaction: He gives the example of an electron, which had the same role in electrical theory, despite changes in understanding its nature. One might talk of its 'natural' (causal) role, rather than its 'explanatory' role (which implies a human viewpoint). |
| 17528 | The dispositional account explains causation, as stimulation and manifestation of dispositions [Bird] |
| Full Idea: The analysis of causation in terms of dispositions provides no conceptual reduction, but it does provide insight into the metaphysics of causation. We then know what causation is - it is the stimulation and manifestation of a disposition. | |
| From: Alexander Bird (Causation and the Manifestation of Powers [2010], p.167) | |
| A reaction: I would say that it offers the essence of causation, by giving a basic explanation of it. See Mumford/Lill Anjum on this. |
| 9493 | We should explain causation by powers, not powers by causation [Bird] |
| Full Idea: The notion of 'causal power' is not to be analysed in terms of causation; if anything, the relationship is the reverse. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 4.2.1 n71) | |
| A reaction: It is a popular view these days to take causation as basic (as opposed to the counterfactual account), but I prefer this view. If anything is basic in nature, it is the dynamic force in the engine room, which is the active powers of substances. |
| 6753 | Laws are more fundamental in science than causes, and laws will explain causes [Bird] |
| Full Idea: I think laws are fundamental and where there is a cause there is always a set of laws that encompasses the cause; identifying a cause will never be the final word in an scientific investigation, but will be open to supplementation by the underlying law. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: I think this is wrong. I would say (from the essentialist angle) that essences have causes, and the laws are the regularities that are caused by the essences. If laws are the lowest level of explanation, why these laws and not others? God? |
| 9494 | Singularism about causes is wrong, as the universals involved imply laws [Bird] |
| Full Idea: While singularists about causation might think that a particular has its causal powers independently of law, it is difficult to see how a universal could have or confer causal powers without generating what we would naturally think of as a law. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 4.2.1 n71) | |
| A reaction: This is a middle road between the purely singularist account (Anscombe) and the fully nomological account. We might say that a caused event will be 'involved in law-like behaviour', without attributing the cause to a law. |
| 17526 | The counterfactual approach makes no distinction between cause and pre-condition [Bird] |
| Full Idea: The counterfactual approach makes no distinction between cause and condition, ...but when the smoke sets off the fire alarm, the smoke is the cause, whereas the presence of the alarm is just the condition. | |
| From: Alexander Bird (Causation and the Manifestation of Powers [2010], p.162) | |
| A reaction: Bird defends the idea that causes are what stimulate dispositions to act. |
| 6762 | Newton's laws cannot be confirmed individually, but only in combinations [Bird] |
| Full Idea: None of Newton's laws individually records anything that can be observed; it is only from combinations of Newton's laws that we can derive the measurable motions of bodies. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: This certainly scuppers any traditional positivist approach to how we confirm laws of nature. It invites the possibility that a different combination might fit the same observations. Experiments attempt to isolate laws. |
| 6763 | Parapsychology is mere speculation, because it offers no mechanisms for its working [Bird] |
| Full Idea: Wegener's theory of continental drift was only accepted when the theory of plate tectonics was developed, providing a mechanism. While some correlations exist for parapsychology, lack of plausible mechanisms leaves it as speculation. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.2) | |
| A reaction: But parapsychology is not even on a par with Wegener's speculation, because his was consistent with known physical laws, whereas parapsychology flatly contradicts them. The so-called correlations are also not properly established. |
| 6772 | Existence requires laws, as inertia or gravity are needed for mass or matter [Bird] |
| Full Idea: I suspect that what we mean by 'mass' and 'matter' depends on our identifying the existence of laws of inertia and gravity; hence the idea of a world without laws is incoherent, for there to be anything at all there must be some laws and some kinds. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.3) | |
| A reaction: I find this counterintuitive. Reasonably stable existence requires something reasonably like laws. We only understand the physical world because we interact with it. But neither of those is remotely as strong as Bird's claim. |
| 9507 | Laws are explanatory relationships of things, which supervene on their essences [Bird] |
| Full Idea: The laws of a domain are the fundamental, general explanatory relationships between kinds, quantities, and qualities of that domain, that supervene upon the essential natures of those things. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 10.1) | |
| A reaction: This is the scientific essentialist view of laws [see entries there, in 'Laws of Nature']. There seems uncertainty between 'kinds' and 'qualities' (with 'quantities' looking like a category mistake). I vote, with Ellis, for natural kinds as the basis. |
| 9488 | Laws are either disposition regularities, or relations between properties [Bird] |
| Full Idea: Instead of viewing laws as regular relationships between dispositional properties and stimulus-manifestation, they can be conceived of as a relation between properties. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 3.4) | |
| A reaction: Bird offers these as the two main views, with the first coming from scientific essentialism, and the second from Armstrong's account of universals. Personally I favour the first, but Bird suggests that powers give the best support for both views. |
| 6740 | 'All uranium lumps are small' is a law, but 'all gold lumps are small' is not [Bird] |
| Full Idea: 'Uranium lumps have mass of less than 1000 kg' is a law, but 'gold lumps have mass of less than 1000kg' is not a law. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: A nice example. Essentialists talk about the nature of the substances; regularity theorists prefer to talk of nested or connected regularities (e.g. about explosions). In induction, how do you decide what your duty requires you to observe? |
| 6741 | There can be remarkable uniformities in nature that are purely coincidental [Bird] |
| Full Idea: Bode's non-law (of 1772, about the gaps between the planets) shows that there can be remarkable uniformities in nature that are purely coincidental. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: If Bode's law really were confirmed, even for asteroids and newly discovered planets, it might suggest that an explanation really is required, and there is some underlying cause. How likely is the coincidence? Perhaps we have no way of telling. |
| 6742 | A law might have no instances, if it was about things that only exist momentarily [Bird] |
| Full Idea: A law might have no instances at all; for example, about the chemical and electrical behaviour of the transuranic elements, which only exist briefly in laboratories. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: Nice example. We need to distinguish, though, (as Bird reminds us) between laws and theories. We have no theories in this area, but there are counterfactual truths about what the transuranic elements would do in certain circumstances. |
| 6743 | If laws are just instances, the law should either have gaps, or join the instances arbitrarily [Bird] |
| Full Idea: For the simple regularity theorist, the function ought to be a gappy one, leaving out values not actually instantiated; …one function would fit the actual points on the graph as well as any other. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: The 'simple' theorist says there is nothing more to a law than its instances. Clearly Bird is right; if the points line up, we join them with a straight line, making counterfactual assumptions about points which were not actually observed. |
| 6744 | Where is the regularity in a law predicting nuclear decay? [Bird] |
| Full Idea: If a law of nuclear physics says that nuclei of a certain kind have a probability p of decaying within time t, what is the regularity here? | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: Hume gives an answer, in terms of regularities observed among previous instances. Nevertheless the figure p given in the law does not itself have any instances, so the law is predicting something that may never have actually happened before. |
| 6747 | Laws cannot explain instances if they are regularities, as something can't explain itself [Bird] |
| Full Idea: It can be objected that laws cannot do the job of explaining their instances if they are merely regularities, ...because something cannot explain itself. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: A nice point. The objection assumes that a law should explain things, rather than just describing them. I take the model to be smoking-and-cancer; the statistics describe what is happening, but only lung biochemistry will explain it. |
| 9496 | That other diamonds are hard does not explain why this one is [Bird] |
| Full Idea: The fact that some other diamonds are hard does not explain why this diamond is hard. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 4.3.2) | |
| A reaction: A very nice aphorism! It pinpoints the whole error of trying to explain the behaviour of the world by citing laws. Why should this item obey that law? Bird prefers 'powers', and so do I. |
| 6748 | Similar appearance of siblings is a regularity, but shared parents is what links them [Bird] |
| Full Idea: There may be a regularity of siblings looking similar, but the tie that binds them is not their similarity, but rather their being born of the same parents. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: A nice objection to the regularity view. Regularities, as so often in philosophy (e.g. Idea 1364), may be the evidence or test for a law, rather than the law itself, which requires causal mechanisms, ultimately based (I think) in essences. |
| 6749 | We can only infer a true regularity if something binds the instances together [Bird] |
| Full Idea: We cannot infer a regularity from its instances unless there is something stronger than the regularity itself binding the instances together. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: Spells out the implication of the example in Idea 6748. The reply to this criticism would be that no account can possibly be given of the 'something stronger' than further regularities, at a lower level (e.g. in the physics). |
| 6803 | If we only infer laws from regularities among observations, we can't infer unobservable entities. [Bird] |
| Full Idea: If the naïve inductivist says we should see well-established regularities among our observations, and take that to be the law or causal connection…this will not help us to infer the existence of unobservable entities. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.8) | |
| A reaction: The obvious solution to this difficulty is an appeal to 'best explanation'. Bird is obviously right that we couldn't survive in the world, let alone do science, if we only acted on what we had actually observed (e.g. many bodies, but not the poison). |
| 6801 | Accidental regularities are not laws, and an apparent regularity may not be actual [Bird] |
| Full Idea: Many actual regularities are not laws (accidental regularities), and many perceived regularities are not actual ones (a summer's worth of observing green leaves). | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.8) | |
| A reaction: These problems are not sufficient to refute the regularity view of laws. Accidental regularities can only be short-lived, and perceived regularities support laws without clinching them. There is an awful lot of regularity behind laws concerning gravity. |
| 9479 | Dispositional essentialism says laws (and laws about laws) are guaranteed regularities [Bird] |
| Full Idea: For the regularity version of dispositional essentialism about laws, laws are those regularities whose truth is guaranteed by the essential dispositional nature of one or more of the constituents. Regularities that supervene on such laws are also laws. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 3.1.2) | |
| A reaction: Even if you accept necessary behaviour resulting from essential dispositions, you still need to distinguish the important regularities from the accidental ones, so the word 'guarantee' is helpful, even if it raises lots of difficulties. |
| 6746 | There may be many laws, each with only a few instances [Bird] |
| Full Idea: It might be that there is a large number of laws each of which has only a small number of instances. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: This is a problem for the Ramsey-Lewis view (Idea 6745) that the laws of nature are a simple, powerful and coherent system. We must be cautious about bringing a priori principles like Ockham's Razor (Idea 3667) to bear on the laws of nature. |
| 6745 | A regularity is only a law if it is part of a complete system which is simple and strong [Bird] |
| Full Idea: The systematic (Ramsey-Lewis) regularity theory says that a regularity is a law of nature if and only if it appears as a theorem or axiom in that true deductive system which achieves a best combination of simplicity and strength. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.1) | |
| A reaction: Personally I don't accept the regularity view of laws, but this looks like the best account anyone has come up with. Individual bunches of regularities can't add up to or demonstrate a law, but coherence with all regularities might do it. |
| 6802 | With strange enough predicates, anything could be made out to be a regularity [Bird] |
| Full Idea: We learned from Goodman's problem that with strange enough predicates anything could be made out to be a regularity. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.8) | |
| A reaction: For Goodman's problem, see Idea 4783. The point, as I see it, is that while predicates can be applied arbitrarily (because they are just linguistic), properties cannot, because they are features of the world. Emeralds are green. |
| 9473 | Laws cannot offer unified explanations if they don't involve universals [Bird] |
| Full Idea: Laws, or what flow from them, are supposed to provide a unified explanation of the behaviours of particulars. Without universals the explanation of the behaviours of things lacks the required unity. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 2.1.2) | |
| A reaction: Sounds a bit question-begging? Gravity seems fairly unified, whereas the frequency of London buses doesn't. Maybe I could unify bus-behaviour by positing a few new universals? The unity should first be in the phenomena, not in the explanation. |
| 9484 | If the universals for laws must be instantiated, a vanishing particular could destroy a law [Bird] |
| Full Idea: If universals exist only where and when they are instantiated, this make serious trouble for the universals view of laws. It would be most odd if a particular, merely by changing its properties, could cause a law to go out of existence. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 3.2.2) | |
| A reaction: This sounds conclusive. He notes that this is probably why Armstrong does not adopt this view (though Lowe seems to favour it). Could there be a possible property (and concomitant law) which was never ever instantiated? |
| 9506 | Salt necessarily dissolves in water, because of the law which makes the existence of salt possible [Bird] |
| Full Idea: We cannot have a world where it is true both that salt exists (which requires Coulomb's Law to be true), and that it fails to dissolve in water (which requires Coulomb's Law to be false). So the dissolving is necessary even if the Law is contingent. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 8.2) | |
| A reaction: Excellent. It is just like the bonfire on the Moon (imaginable through ignorance, but impossible). People who assert that the solubility of salt is contingent tend not to know much about chemistry. |
| 23713 | Most laws supervene on fundamental laws, which are explained by basic powers [Bird, by Friend/Kimpton-Nye] |
| Full Idea: According to Bird, non-fundamental laws supervene on fundamental laws, and so are ultimately explained by fundamental powers. | |
| From: report of Alexander Bird (Nature's Metaphysics [2007]) by Friend/Kimpton-Nye - Dispositions and Powers 3.6.1 | |
| A reaction: This looks like the picture I subscribe to. Roughly, fundamental laws are explained by powers, and non-fundamental laws are explained by properties, which are complexes of powers. 'Fundamental' may not be a precise term! |
| 6789 | If flame colour is characteristic of a metal, that is an empirical claim needing justification [Bird] |
| Full Idea: I might say that flame colours are a characteristic feature of metals, but this is an empirical proposition which is in part about the unobserved, and stands in need of justification. | |
| From: Alexander Bird (Philosophy of Science [1998], Ch.5) | |
| A reaction: This draws attention to the fact that essentialism is not just a metaphysical theory, but is also part of the scientific enterprise. Among things to research about metals is the reason why they have a characteristic flame. |
| 9489 | Essentialism can't use conditionals to explain regularities, because of possible interventions [Bird] |
| Full Idea: The straightforward dispositional essentialist account of laws by subjunctive conditionals is false because dispositions typically suffer from finks and antidotes. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 3.4) | |
| A reaction: [Finks and antidotes intervene before a disposition can take effect] This seems very persuasive to me, and shows why you can't just explain laws as counterfactual or conditional claims. Explanation demands what underlies them. |
| 6807 | In Newton mass is conserved, but in Einstein it can convert into energy [Bird] |
| Full Idea: According to Newton mass is conserved, while in Einstein's theory mass is not conserved but can be converted into and from energy. | |
| From: Alexander Bird (Philosophy of Science [1998]) | |
| A reaction: Perhaps this is the most fundamental difference between the theories. It certainly suggests that 'mass' was a conventional concept rather than a natural one. Maybe the relative notion of 'weight' is more natural than 'mass'. |
| 9504 | The relational view of space-time doesn't cover times and places where things could be [Bird] |
| Full Idea: The obvious problem with the simple relational view of space and time is that it fails to account for the full range of spatio-temporal possibility. There seem to be times and places where objects and events could be, but are not. | |
| From: Alexander Bird (Nature's Metaphysics [2007], 7.3.2) | |
| A reaction: This view seems strongly supported by intuition. I certainly don't accept the views of physicists and cosmologists on the subject, because they seem to approach the whole thing too instrumentally. |