93 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! |
11912 | Substantive metaphysics says what a property is, not what a predicate means [Molnar] |
Full Idea: The motto of what is presented here is 'less conceptual analysis, more metaphysics', where the distinction is equivalent to the distinction between saying what 'F' means and saying what being F is. | |
From: George Molnar (Powers [1998], 1.1) | |
A reaction: This seems to me to capture exactly the spirit of metaphysics since Saul Kripke's work, though some people engaged in it seem to me to be trapped in an outdated linguistic view of the matter. Molnar credits Locke as the source of his view. |
5750 | Consistency is modal, saying propositions are consistent if they could be true together [Melia] |
Full Idea: Consistency is a modal notion: a set of propositions is consistent iff all the members of the set could be true together. | |
From: Joseph Melia (Modality [2003], Ch.6) | |
A reaction: This shows why Kantian ethics, for example, needs a metaphysical underpinning. Maybe Kant should have believed in the reality of Leibnizian possible worlds? An account of reason requires an account of necessity and possibility. |
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. |
11920 | A real definition gives all the properties that constitute an identity [Molnar] |
Full Idea: A real definition expresses the sum of the properties that constitute the identity of the thing defined. | |
From: George Molnar (Powers [1998], 1.4.4) | |
A reaction: This is a standard modern view among modern essentialists, and one which I believe can come into question. It seems to miss out the fact that an essence will also explain the possible functions and behaviours of a thing. Explanation seems basic. |
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 |
5737 | Predicate logic has connectives, quantifiers, variables, predicates, equality, names and brackets [Melia] |
Full Idea: First-order predicate language has four connectives, two quantifiers, variables, predicates, equality, names, and brackets. | |
From: Joseph Melia (Modality [2003], Ch.2) | |
A reaction: Look up the reference for the details! The spirit of logic is seen in this basic framework, and the main interest is in the ontological commitment of the items on the list. The list is either known a priori, or it is merely conventional. |
5744 | First-order predicate calculus is extensional logic, but quantified modal logic is intensional (hence dubious) [Melia] |
Full Idea: First-order predicate calculus is an extensional logic, while quantified modal logic is intensional (which has grave problems of interpretation, according to Quine). | |
From: Joseph Melia (Modality [2003], Ch.3) | |
A reaction: The battle is over ontology. Quine wants the ontology to stick with the values of the variables (i.e. the items in the real world that are quantified over in the extension). The rival view arises from attempts to explain necessity and counterfactuals. |
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' |
5740 | Second-order logic needs second-order variables and quantification into predicate position [Melia] |
Full Idea: Permitting quantification into predicate position and adding second-order variables leads to second-order logic. | |
From: Joseph Melia (Modality [2003], Ch.2) | |
A reaction: Often expressed by saying that we now quantify over predicates and relations, rather than just objects. Depends on your metaphysical commitments. |
5741 | If every model that makes premises true also makes conclusion true, the argument is valid [Melia] |
Full Idea: In first-order predicate calculus validity is defined thus: an argument is valid iff every model that makes the premises of the argument true also makes the conclusion of the argument true. | |
From: Joseph Melia (Modality [2003], Ch.2) | |
A reaction: See Melia Ch. 2 for an explanation of a 'model'. Traditional views of validity tend to say that if the premises are true the conclusion has to be true (necessarily), but this introduces the modal term 'necessarily', which is controversial. |
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. |
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'? |
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 Michčle 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) |
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. |
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'? |
11919 | Ontological dependence rests on essential connection, not necessary connection [Molnar] |
Full Idea: Ontological dependence is better understood in terms of an essential connection, rather than simply a necessary connection. | |
From: George Molnar (Powers [1998], 1.4.4) | |
A reaction: This seems to be an important piece in the essentialist jigsaw. Apart from essentialism, I can't think of any doctrine which offers any sort of explanation of the self-evident fact of certain ontological dependencies. |
5735 | Maybe names and predicates can capture any fact [Melia] |
Full Idea: Some philosophers think that any fact can be captured in a language containing only names and predicates. | |
From: Joseph Melia (Modality [2003], Ch.2) | |
A reaction: The problem case Melia is discussing is modal facts, such as 'x is possible'. It is hard to see how 'possible' could be an ordinary predicate, but then McGinn claims that 'existence' is, and that there are some predicates with unusual characters. |
5736 | No sort of plain language or levels of logic can express modal facts properly [Melia] |
Full Idea: Some philosophers say that modal facts cannot be expressed either by name/predicate language, or by first-order predicate calculus, or even by second-order logic. | |
From: Joseph Melia (Modality [2003], Ch.2) | |
A reaction: If 'possible' were a predicate, none of this paraphernalia would be needed. If possible worlds are accepted, then the quantifiers of first-order predicate calculus will do the job. If neither of these will do, there seems to be a problem. |
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'? |
11929 | The three categories in ontology are objects, properties and relations [Molnar] |
Full Idea: The ontologically fundamental categories are three in number: Objects, Properties, and Relations. | |
From: George Molnar (Powers [1998], 2 Intr) | |
A reaction: We need second-order logic to quantify over all of these. The challenge to this view might be that it is static, and needs the addition of processes or events. Molnar rejects facts and states of affairs. |
11927 | Reflexive relations are syntactically polyadic but ontologically monadic [Molnar] |
Full Idea: Reflexive relations are, and non-reflexive relations may be, monadic in the ontological sense although they are syntactically polyadic. | |
From: George Molnar (Powers [1998], 1.4.5) | |
A reaction: I find this a very helpful distinction, as I have never quite understood reflexive relations as 'relations', even in the most obvious cases, such as self-love or self-slaughter. |
11915 | If atomism is true, then all properties derive from ultimate properties [Molnar] |
Full Idea: If a priori atomism is a true theory of the world, then all properties are derivative from ultimate properties. | |
From: George Molnar (Powers [1998], 1.4.1) | |
A reaction: Presumably there is a physicalist metaphysic underlying this, which means that even abstract properties derive ultimately from these physical atoms. Unless we want to postulate logical atoms, or monads, or some such weird thing. |
11916 | 'Being physical' is a second-order property [Molnar] |
Full Idea: A property like 'being physical' is just a second-order property. ...It is not required as a first-order property. ...Higher-order properties earn their keep as necessity-makers. | |
From: George Molnar (Powers [1998], 1.4.2) | |
A reaction: I take this to be correct and very important. People who like 'abundant' properties don't make this distinction about orders (of levels of abstraction, I would say), so the whole hierarchy has an equal status in ontology, which is ridiculous. |
11956 | 'Categorical properties' are those which are not powers [Molnar] |
Full Idea: The canonical name for a property that is a non-power is 'categorical property'. | |
From: George Molnar (Powers [1998], 10.2) | |
A reaction: Molnar objects that this implies that powers cannot be used categorically, and refuses to use the term. There seems to be uncertainty over whether the term refers to necessity, or to the ability to categorise. I'm getting confused myself. |
11928 | Are tropes transferable? If they are, that is a version of Platonism [Molnar] |
Full Idea: Are tropes transferable? ...If tropes are not dependent on their bearers, that is a trope-theoretic version of Platonism. | |
From: George Molnar (Powers [1998], 1.4.6) | |
A reaction: These are the sort of beautifully simple questions that we pay philosophers to come up with. If they are transferable, what was the loose bond which connected them? If they aren't, then what individuates them? |
11933 | A power's type-identity is given by its definitive manifestation [Molnar] |
Full Idea: A power's type-identity is given by its definitive manifestation. | |
From: George Molnar (Powers [1998], 3.1) | |
A reaction: Presumably there remains an I-know-not-what that lurks behind the manifestation, which is beyond our limits of cognizance. The ultimate reality of the world has to be unknowable. |
11932 | Powers have Directedness, Independence, Actuality, Intrinsicality and Objectivity [Molnar] |
Full Idea: The basic features of powers are: Directedness (to some outcome); Independence (from their manifestations); Actuality (not mere possibilities); Intrinsicality (not relying on other objects) and Objectivity (rather than psychological). | |
From: George Molnar (Powers [1998], 2.4) | |
A reaction: [compression of his list] This offering is why Molnar's book is important, because no one else seems to get to grips with trying to pin down what a power is, and hence their role. |
11934 | The physical world has a feature very like mental intentionality [Molnar] |
Full Idea: Something very much like mental intentionality is a pervasive and ineliminable feature of the physical world. | |
From: George Molnar (Powers [1998], 3.2) | |
A reaction: I like this, because it offers a continuous account of mind and world. The idea that intentionality is some magic ingredient that marks off a non-physical type of reality is nonsense. See Fodor's attempts to reduce intentionality. |
11947 | Dispositions and external powers arise entirely from intrinsic powers in objects [Molnar] |
Full Idea: I propose a generalization: that all dispositional and extrinsic predicates that apply to an object, do so by virtue of intrinsic powers borne by the object. | |
From: George Molnar (Powers [1998], 6.3) | |
A reaction: This is the clearest statement of the 'powers' view of nature, and the one with which I agree. An interesting question is whether powers or objects are more basic in our ontology. Are objects just collections of causal powers? What has the power? |
11953 | Some powers are ungrounded, and others rest on them, and are derivative [Molnar] |
Full Idea: Some powers are grounded and some are not. ...All derivative powers ultimately derive from ungrounded powers. | |
From: George Molnar (Powers [1998], 8.5.2) | |
A reaction: It is tempting to use the term 'property' for the derivative powers, reserving 'power' for something which is basic. Molnar makes a plausible case, though. |
11952 | The Standard Model suggest that particles are entirely dispositional, and hence are powers [Molnar] |
Full Idea: In the Standard Model of physics the fundamental physical magnitudes are represented as ones whose whole nature is exhausted by the dispositionality, ..so there is a strong presumption that the properties of subatomic particles are powers. | |
From: George Molnar (Powers [1998], 8.4.3) | |
A reaction: A very nice point, because it asserts not merely that we should revise our metaphysic to endorse powers, but that we are actually already operating with exactly that view, in so far as we are physicalist. |
11943 | Dispositions can be causes, so they must be part of the actual world [Molnar] |
Full Idea: Dispositions can be causes. What is not actual cannot be a cause or any part of a cause. Merely possible events are not actual, and that makes them causally impotent. The claim that powers are causally potent has strong initial plausibility. | |
From: George Molnar (Powers [1998], 5) | |
A reaction: [He credits Mellor 1974 for this idea] He will need to show how dispositions can be causes (other than, presumably, being anticipated or imagined by conscious minds), which he says he will do in Ch. 12. |
11939 | If powers only exist when actual, they seem to be nomadic, and indistinguishable from non-powers [Molnar] |
Full Idea: Two arguments against Megaran Actualism are that it turns powers into nomads: they come and go, depending on whether they are being exercised or not. And it stops us from distinguishing between unexercised powers and absent powers. | |
From: George Molnar (Powers [1998], 4.3.1) | |
A reaction: See Idea 11938 for Megaran Actualism. Molnar takes these objections to be fairly decisive, but if the Megarans are denying the existence of latent powers, they aren't going to be bothered by nomadism or the lack of distinction. |
11914 | Platonic explanations of universals actually diminish our understanding [Molnar] |
Full Idea: We understand less after a platonic explanation of universals than we understand before it was given. | |
From: George Molnar (Powers [1998], 1.2) | |
A reaction: That pretty much sums up my view, and it pretty well sums up my view of religion as well. I thought I understood what numbers were until Frege told me that they were abstract objects, some sort of higher-order set. |
11913 | For nominalists, predicate extensions are inexplicable facts [Molnar] |
Full Idea: For the nominalist, belonging to the extension of a predicate is just an inexplicable ultimate fact. | |
From: George Molnar (Powers [1998], 1.2) | |
A reaction: I sometimes think of myself as a nominalist, but when it is summarised in Molnar's way I back off. He seem to be offering a third way, between platonic realism and nominalism. It is physical essentialist realism, I think. |
11962 | Nominalists only accept first-order logic [Molnar] |
Full Idea: A nominalist will only countenance first-order logic. | |
From: George Molnar (Powers [1998], 12.2.2) | |
A reaction: This is because nominalist will not acknowledge properties as entities to be quantified over. Plural quantification seems to be a strategy for extending first-order logic while retaining nominalist sympathies. |
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. |
11917 | Structural properties are derivate properties [Molnar] |
Full Idea: Structural properties are clear examples of derivative properties. | |
From: George Molnar (Powers [1998], 1.4.3) | |
A reaction: This is an important question in the debate. Presumably you can't just reduce structural properties to more basic ones, because one set of basic properties might appear in many different structures. Ellis defends structural properties in metaphysics. |
11955 | There are no 'structural properties', as properties with parts [Molnar] |
Full Idea: There are no 'structural properties', if by that we mean a property that has properties as parts. | |
From: George Molnar (Powers [1998], 9.1.2) | |
A reaction: There do seem to be properties that result from arranging more basic properties in one way rather than another (e.g. arranging the metal in a knife to be 'sharp'). But I think Molnar is right that they are not part of basic ontology. |
11918 | The essence of a thing need not include everything that is necessarily true of it [Molnar] |
Full Idea: Pre-theoretically it does not seem to be the case that what is essential to a thing includes everything that is necessarily true of that thing. | |
From: George Molnar (Powers [1998], 1.4.4) | |
A reaction: This seems to me to be true. The simple point, which I take to be obvious, is that essential properties must at the very least be in some way important, whereas necessities can be trivial. I favour the idea that the essences create the necessities. |
5746 | The Identity of Indiscernibles is contentious for qualities, and trivial for non-qualities [Melia] |
Full Idea: If the Identity of Indiscernibles is referring to qualitative properties, such as 'being red' or 'having mass', it is contentious; if it is referring to non-qualitative properties, such as 'member of set s' or 'brother of a', it is true but trivial. | |
From: Joseph Melia (Modality [2003], Ch.3 n 11) | |
A reaction: I would say 'false' rather than 'contentious'. No one has ever offered a way of distinguishing two electrons, but that doesn't mean there is just one (very busy) electron. The problem is that 'indiscernible' is only an epistemological concept. |
5738 | We may be sure that P is necessary, but is it necessarily necessary? [Melia] |
Full Idea: We may have fairly firm beliefs as to whether or not P is necessary, but many of us find ourselves at a complete loss when wondering whether or not P is necessarily necessary. | |
From: Joseph Melia (Modality [2003], Ch.2) | |
A reaction: I think it is questions like this which are pushing philosophy back towards some sort of rationalism. See Idea 3651, for example. A regress of necessities would be mad, so necessity must be taken as self-evident (in itself, though maybe not to us). |
5732 | 'De re' modality is about things themselves, 'de dicto' modality is about propositions [Melia] |
Full Idea: In cases of 'de re' modality, it is a particular thing that has the property essentially or accidentally; where the modality attaches to the proposition, it is 'de dicto' - it is the whole truth that all bachelors are unmarried that is necessary. | |
From: Joseph Melia (Modality [2003], Ch.1) | |
A reaction: This seems to me one of the most important distinctions in metaphysics (as practised by analytical philosophers, who like distinctions). The first type leads off into the ontology, the second type veers towards epistemology. |
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. |
11963 | What is the truthmaker for a non-existent possible? [Molnar] |
Full Idea: What is the nature of the truthmaker for 'It is possible that p' in cases where p itself is false? | |
From: George Molnar (Powers [1998], 12.2.2) | |
A reaction: Molnar mentions three views: there is a different type of being for possibilia (Meinong), or possibilia exist, or possibilia are merely represented. The third view is obviously correct, though I presume possibilia to be based on actual powers. |
5739 | Sometimes we want to specify in what ways a thing is possible [Melia] |
Full Idea: Sometimes we want to count the ways in which something is possible, or say that there are many ways in which a certain thing is possible. | |
From: Joseph Melia (Modality [2003], Ch.2) | |
A reaction: This is a basic fact about talk of 'possibility'. It is not an all-or-nothing property of a situation. There can be 'faint' possibilities of things. The proximity of some possible worlds, especially those sharing our natural laws, is one answer. |
5734 | Possible worlds make it possible to define necessity and counterfactuals without new primitives [Melia] |
Full Idea: In modal logic the concepts of necessity and counterfactuals are not interdefinable, so the language needs two primitives to represent them, but with the machinery of possible worlds they are defined by what is the case in all worlds, or close worlds. | |
From: Joseph Melia (Modality [2003], Ch.1) | |
A reaction: If your motivation is to reduce ontology to the barest of minimums (which it was for David Lewis) then it is paradoxical that the existence of possible worlds may be the way to achieve it. I doubt, though, whether a commitment to their reality is needed. |
5742 | In possible worlds semantics the modal operators are treated as quantifiers [Melia] |
Full Idea: The central idea in possible worlds semantics is that the modal operators are treated as quantifiers. | |
From: Joseph Melia (Modality [2003], Ch.2) | |
A reaction: It seems an essential requirement of metaphysics that an account be given of possibility and necessity, and it is also a good dream to keep the ontology simple. Commitment to possible worlds is the bizarre outcome of this dream. |
5743 | If possible worlds semantics is not realist about possible worlds, logic becomes merely formal [Melia] |
Full Idea: It has proved difficult to justify possible worlds semantics without accepting possible worlds. Without a secure metaphysical underpinning, the results in logic are in danger of having nothing more than a formal significance. | |
From: Joseph Melia (Modality [2003], Ch.2) | |
A reaction: This makes nicely clear why Lewis's controversial modal realism has to be taken seriously. It appears that the key problem is truth, because that is needed to define validity, but you can't have truth without some sort of metaphysics. |
5749 | Possible worlds could be real as mathematics, propositions, properties, or like books [Melia] |
Full Idea: One can be a realist about possible worlds without adopting Lewis's extreme views; they might be abstract or mathematical entities; they might be sets of propositions or maximal uninstantiated properties; they might be like books or pictures. | |
From: Joseph Melia (Modality [2003], Ch.6) | |
A reaction: My intuition is that once you go down the road of realism about possible worlds, Lewis's full concrete realism looks at least as attractive as any of these options. You can discuss the 'average man' in an economic theory without realism. |
5751 | The truth of propositions at possible worlds are implied by the world, just as in books [Melia] |
Full Idea: Propositions are true at possible worlds in much the same way as they are true at books: by being implied by the book. | |
From: Joseph Melia (Modality [2003], Ch.7) | |
A reaction: An intriguing way to introduce the view that possible worlds should be seen as like books. The truth-makers of propositions about the actual world are items in it, but the truth-makers in novels (say) are the conditions of the whole work as united. |
11951 | Hume allows interpolation, even though it and extrapolation are not actually valid [Molnar] |
Full Idea: In his 'shade of blue' example, Hume is (sensibly) endorsing a type of reasoning - interpolation - that is widely used by rational thinkers. Too bad that interpolation and extrapolation are incurably invalid. | |
From: George Molnar (Powers [1998], 7.2.3) | |
A reaction: Interpolation and extrapolation are two aspects of inductive reasoning which contribute to our notion of best explanation. Empiricism has to allow at least some knowledge which goes beyond strict direct experience. |
11936 | The two ways proposed to distinguish mind are intentionality or consciousness [Molnar] |
Full Idea: There have only been two serious proposals for distinguishing mind from matter. One appeals to intentionality, as per Brentano and his medieval precursors. The other, harking back to Descartes, Locke and empiricism, uses the capacity for consciousness. | |
From: George Molnar (Powers [1998], 3.5.3) | |
A reaction: Personally I take both of these to be reducible, and hence have no place for 'minds' in my ontology. Focusing on Chalmers's 'Hard Question' was the shift from the intentionality view to the consciousness view which is now more popular. |
11935 | Physical powers like solubility and charge also have directedness [Molnar] |
Full Idea: Contrary to the Brentano Thesis, physical powers, such as solubility or electromagnetic charge, also have that direction toward something outside themselves that is typical of psychological attributes. | |
From: George Molnar (Powers [1998], 3.4) | |
A reaction: I think this decisively undermines any strong thesis that 'intentionality is the mark of the mental'. I take thought to be just a fancy development of the physical powers of the physical world. |
11944 | Rule occasionalism says God's actions follow laws, not miracles [Molnar] |
Full Idea: Rule occasionalists (Arnauld, Bayle) say that on their view the results of God's action are the nomic regularities of nature, and not a miracle. | |
From: George Molnar (Powers [1998], 6.1) | |
A reaction: This is clearly more plausible that Malebranche's idea that God constantly intervenes. I take it as a nice illustration of the fact that 'laws of nature' were mainly invented by us to explain how God could control his world. Away with them! |
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). |
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) |
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. |
5748 | We accept unverifiable propositions because of simplicity, utility, explanation and plausibility [Melia] |
Full Idea: Many philosophers now concede that it is rational to accept a proposition not because we can directly verify it but because it is supported by considerations of simplicity, theoretical utility, explanatory power and/or intuitive plausibility. | |
From: Joseph Melia (Modality [2003], Ch.5) | |
A reaction: This suggests how the weakness of logical positivism may have led us to the concept of epistemic virtues (such as those listed), which are, of course, largely a matter of community consensus, just as the moral virtues are. |
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. |
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. |
11960 | Singular causation is prior to general causation; each aspirin produces the aspirin generalization [Molnar] |
Full Idea: I take for granted the primacy of singular causation. A singular causal state of affairs is not constituted by a generalization. 'Aspirin relieves headache' is made true by 'This/that aspirin relieves this/that headache'. | |
From: George Molnar (Powers [1998], 12.1) | |
A reaction: [He cites Tooley for the opposite view] I wholly agree with Molnar, and am inclined to link it with the primacy of individual essences over kind essences. |
11937 | We should analyse causation in terms of powers, not vice versa [Molnar] |
Full Idea: Causal analyses of powers pre-empt the correct account of causation in terms of powers. | |
From: George Molnar (Powers [1998], 4.2.3) | |
A reaction: I think this is my preferred view. The crucial point is that powers are active, so one is not needing to add some weird 'causation' ingredient to a world which would otherwise be passive and inert. That is a relic from the interventions of God. |
11954 | We should analyse causation in terms of powers [Molnar] |
Full Idea: We should give up any causal analysis of powers, ..so we should try to analyse causation in terms of powers. | |
From: George Molnar (Powers [1998], 8.5.3) | |
A reaction: It may be hard to explain what powers are, or identify them, if you can't say that they cause things to happen. I am torn between Molnar's view, and the view that causation is primitive. |
11961 | Causal dependence explains counterfactual dependence, not vice versa [Molnar] |
Full Idea: The counterfactual analysis is open to the Euthyphro objection: it is causal dependence that explains any counterfactual dependence rather than vice versa. | |
From: George Molnar (Powers [1998], 12.1) | |
A reaction: I take views like the counterfactual analysis of causation to arise from empiricists who are bizarrely reluctant to adopt plausible best explainations (such as powers and essences). |
11959 | Science works when we assume natural kinds have essences - because it is true [Molnar] |
Full Idea: Investigations premissed on the assumption that natural kinds have essences, that in particular the fundamental natural kinds have only essential intrinsic properties, tend to be practically successful because the assumption is true. | |
From: George Molnar (Powers [1998], 11.3) | |
A reaction: The point is made against a pragmatist approach to the problem by Nancy Cartwright. I take the starting point for scientific essentialism to be an empirical observation, that natural kinds seem to be very very stable. See Idea 8153. |
9448 | Location in space and time are non-power properties [Molnar, by Mumford] |
Full Idea: Molnar argues that some properties are non-powers, and he cites spatial location, spatial orientation, and temporal location. | |
From: report of George Molnar (Powers [1998], 158-62) by Stephen Mumford - Laws in Nature 11.4 | |
A reaction: Although you might say an event happened 'because' of an item on this list, this doesn't feel right to me. The ability to arrest someone is a power, but being at the scene of the crime isn't. It's an opportunity for a power. |
11930 | One essential property of a muon doesn't entail the others [Molnar] |
Full Idea: The muon has mass 106.2 MeV, unit negative charge, and spin a half. The electron and tauon have unit negative charge, but electrons are 200 times less massive, and tauons 17 times more massive. Its essential properties are not mutually entailing. | |
From: George Molnar (Powers [1998], 2.1) | |
A reaction: This rejects a popular idea of scientific essentialism, that the essence is the set of properties which entail the non-essential properties (and not vice versa), a view which I had hitherto found rather appealing. |
11957 | It is contingent which kinds and powers exist in the world [Molnar] |
Full Idea: It is a contingent matter that the world contains the exact natural kinds it does, and hence it is a contingent matter that it contains the very powers it does. | |
From: George Molnar (Powers [1998], 10.3) | |
A reaction: I take this to be correct (for all we know). It would be daft to claim that the regularities of the universe are necessarily that way, but it is not daft to say that the stuff of the universe necessitates the pattern of what happens. |
11921 | The laws of nature depend on the powers, not the other way round [Molnar] |
Full Idea: What powers there are does not depend on what laws there are, but vice versa, what laws obtain in the world is a function of what powers are to be found in that world. | |
From: George Molnar (Powers [1998], 1.4.5) | |
A reaction: This old idea may well be the most important realisation of modern times. I take the 'law' view to be based on a religious view of the world (see Idea 5470). There is still room to believe in a divine creator of the bewildering underlying powers. |
11931 | Energy fields are discontinuous at the very small [Molnar] |
Full Idea: We know that all energy fields are discontinuous below the distance measured by Planck's constant h. The physical world ultimately consists of discrete objects. | |
From: George Molnar (Powers [1998], 2.2) | |
A reaction: This is where quantum theory clashes with relativity, since the latter holds space to be a continuum. I'm not sure about Molnar's use of the word 'objects' here. |