61 ideas
| 9955 | Contextual definitions replace a complete sentence containing the expression [George/Velleman] |
| Full Idea: A contextual definition shows how to analyse an expression in situ, by replacing a complete sentence (of a particular form) in which the expression occurs by another in which it does not. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.2) | |
| A reaction: This is a controversial procedure, which (according to Dummett) Frege originally accepted, and later rejected. It might not be the perfect definition that replacing just the expression would give you, but it is a promising step. |
| 10031 | Impredicative definitions quantify over the thing being defined [George/Velleman] |
| Full Idea: When a definition contains a quantifier whose range includes the very entity being defined, the definition is said to be 'impredicative'. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.2) | |
| A reaction: Presumably they are 'impredicative' because they do not predicate a new quality in the definiens, but make use of the qualities already known. |
| 10098 | The 'power set' of A is all the subsets of A [George/Velleman] |
| Full Idea: The 'power set' of A is all the subsets of A. P(A) = {B : B ⊆ A}. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) |
| 10099 | The 'ordered pair' <a, b>, for two sets a and b, is the set {{a, b},{a}} [George/Velleman] |
| Full Idea: The 'ordered pair' <a, b>, for two sets a and b, is the set {{a, b},{a}}. The existence of this set is guaranteed by three applications of the Axiom of Pairing. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) | |
| A reaction: See Idea 10100 for the Axiom of Pairing. |
| 10101 |
Cartesian Product A x B: the set of all ordered pairs |
| Full Idea: The 'Cartesian Product' of any two sets A and B is the set of all ordered pairs <a, b> in which a ∈ A and b ∈ B, and it is denoted as A x B. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) |
| 10103 | Grouping by property is common in mathematics, usually using equivalence [George/Velleman] |
| Full Idea: The idea of grouping together objects that share some property is a common one in mathematics, ...and the technique most often involves the use of equivalence relations. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) |
| 10104 | 'Equivalence' is a reflexive, symmetric and transitive relation; 'same first letter' partitions English words [George/Velleman] |
| Full Idea: A relation is an equivalence relation if it is reflexive, symmetric and transitive. The 'same first letter' is an equivalence relation on the set of English words. Any relation that puts a partition into clusters will be equivalence - and vice versa. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) | |
| A reaction: This is a key concept in the Fregean strategy for defining numbers. |
| 10096 | Even the elements of sets in ZFC are sets, resting on the pure empty set [George/Velleman] |
| Full Idea: ZFC is a theory concerned only with sets. Even the elements of all of the sets studied in ZFC are also sets (whose elements are also sets, and so on). This rests on one clearly pure set, the empty set Φ. ..Mathematics only needs pure sets. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) | |
| A reaction: This makes ZFC a much more metaphysically comfortable way to think about sets, because it can be viewed entirely formally. It is rather hard to disentangle a chair from the singleton set of that chair. |
| 10097 | Axiom of Extensionality: for all sets x and y, if x and y have the same elements then x = y [George/Velleman] |
| Full Idea: The Axiom of Extensionality says that for all sets x and y, if x and y have the same elements then x = y. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) | |
| A reaction: This seems fine in pure set theory, but hits the problem of renates and cordates in the real world. The elements coincide, but the axiom can't tell you why they coincide. |
| 10100 | Axiom of Pairing: for all sets x and y, there is a set z containing just x and y [George/Velleman] |
| Full Idea: The Axiom of Pairing says that for all sets x and y, there is a set z containing x and y, and nothing else. In symbols: ∀x∀y∃z∀w(w ∈ z ↔ (w = x ∨ w = y)). | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) | |
| A reaction: See Idea 10099 for an application of this axiom. |
| 17900 | The Axiom of Reducibility made impredicative definitions possible [George/Velleman] |
| Full Idea: The Axiom of Reducibility ...had the effect of making impredicative definitions possible. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) |
| 10109 | ZFC can prove that there is no set corresponding to the concept 'set' [George/Velleman] |
| Full Idea: Sets, unlike extensions, fail to correspond to all concepts. We can prove in ZFC that there is no set corresponding to the concept 'set' - that is, there is no set of all sets. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.4) | |
| A reaction: This is rather an important point for Frege. However, all concepts have extensions, but they may be proper classes, rather than precisely defined sets. |
| 10405 | In the iterative conception of sets, they form a natural hierarchy [Swoyer] |
| Full Idea: In the iterative conception of sets, they form a natural hierarchy. | |
| From: Chris Swoyer (Properties [2000], 4.1) |
| 10108 | As a reduction of arithmetic, set theory is not fully general, and so not logical [George/Velleman] |
| Full Idea: The problem with reducing arithmetic to ZFC is not that this theory is inconsistent (as far as we know it is not), but rather that is not completely general, and for this reason not logical. For example, it asserts the existence of sets. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.4) | |
| A reaction: Note that ZFC has not been proved consistent. |
| 10111 | Asserting Excluded Middle is a hallmark of realism about the natural world [George/Velleman] |
| Full Idea: A hallmark of our realist stance towards the natural world is that we are prepared to assert the Law of Excluded Middle for all statements about it. For all statements S, either S is true, or not-S is true. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.4) | |
| A reaction: Personally I firmly subscribe to realism, so I suppose I must subscribe to Excluded Middle. ...Provided the statement is properly formulated. Or does liking excluded middle lead me to realism? |
| 10407 | Logical Form explains differing logical behaviour of similar sentences [Swoyer] |
| Full Idea: 'Logical Form' is a technical notion motivated by the observation that sentences with a similar surface structure may exhibit quite different logical behaviour. | |
| From: Chris Swoyer (Properties [2000], 4.2) | |
| A reaction: [Swoyer goes on to give some nice examples] The tricky question is whether each sentence has ONE logical form. Pragmatics warns us of the dangers. One needs to check numerous inferences from a given sentences, not just one. |
| 10129 | A 'model' is a meaning-assignment which makes all the axioms true [George/Velleman] |
| Full Idea: A 'model' of a theory is an assignment of meanings to the symbols of its language which makes all of its axioms come out true. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.7) | |
| A reaction: If the axioms are all true, and the theory is sound, then all of the theorems will also come out true. |
| 10105 | Differences between isomorphic structures seem unimportant [George/Velleman] |
| Full Idea: Mathematicians tend to regard the differences between isomorphic mathematical structures as unimportant. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) | |
| A reaction: This seems to be a pointer towards Structuralism as the underlying story in mathematics. The intrinsic character of so-called 'objects' seems unimportant. How theories map onto one another (and onto the world?) is all that matters? |
| 10119 | Consistency is a purely syntactic property, unlike the semantic property of soundness [George/Velleman] |
| Full Idea: Consistency is a purely syntactic property, unlike the semantic property of soundness. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.6) |
| 10126 | A 'consistent' theory cannot contain both a sentence and its negation [George/Velleman] |
| Full Idea: If there is a sentence such that both the sentence and its negation are theorems of a theory, then the theory is 'inconsistent'. Otherwise it is 'consistent'. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.7) |
| 10120 | Soundness is a semantic property, unlike the purely syntactic property of consistency [George/Velleman] |
| Full Idea: Soundness is a semantic property, unlike the purely syntactic property of consistency. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.6) |
| 10127 | A 'complete' theory contains either any sentence or its negation [George/Velleman] |
| Full Idea: If there is a sentence such that neither the sentence nor its negation are theorems of a theory, then the theory is 'incomplete'. Otherwise it is 'complete'. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.7) | |
| A reaction: Interesting questions are raised about undecidable sentences, irrelevant sentences, unknown sentences.... |
| 10106 | Rational numbers give answers to division problems with integers [George/Velleman] |
| Full Idea: We can think of rational numbers as providing answers to division problems involving integers. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) | |
| A reaction: Cf. Idea 10102. |
| 10102 | The integers are answers to subtraction problems involving natural numbers [George/Velleman] |
| Full Idea: In defining the integers in set theory, our definition will be motivated by thinking of the integers as answers to subtraction problems involving natural numbers. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) | |
| A reaction: Typical of how all of the families of numbers came into existence; they are 'invented' so that we can have answers to problems, even if we can't interpret the answers. It it is money, we may say the minus-number is a 'debt', but is it? Cf Idea 10106. |
| 10107 | Real numbers provide answers to square root problems [George/Velleman] |
| Full Idea: One reason for introducing the real numbers is to provide answers to square root problems. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) | |
| A reaction: Presumably the other main reasons is to deal with problems of exact measurement. It is interesting that there seem to be two quite distinct reasons for introducing the reals. Cf. Ideas 10102 and 10106. |
| 9946 | Logicists say mathematics is applicable because it is totally general [George/Velleman] |
| Full Idea: The logicist idea is that if mathematics is logic, and logic is the most general of disciplines, one that applies to all rational thought regardless of its content, then it is not surprising that mathematics is widely applicable. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.2) | |
| A reaction: Frege was keen to emphasise this. You are left wondering why pure logic is applicable to the physical world. The only account I can give is big-time Platonism, or Pythagoreanism. Logic reveals the engine-room of nature, where the design is done. |
| 10125 | The classical mathematician believes the real numbers form an actual set [George/Velleman] |
| Full Idea: Unlike the intuitionist, the classical mathematician believes in an actual set that contains all the real numbers. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.6) |
| 17899 | Second-order induction is stronger as it covers all concepts, not just first-order definable ones [George/Velleman] |
| Full Idea: The first-order version of the induction axiom is weaker than the second-order, because the latter applies to all concepts, but the first-order applies only to concepts definable by a formula in the first-order language of number theory. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.7 n7) |
| 10128 | The Incompleteness proofs use arithmetic to talk about formal arithmetic [George/Velleman] |
| Full Idea: The idea behind the proofs of the Incompleteness Theorems is to use the language of Peano Arithmetic to talk about the formal system of Peano Arithmetic itself. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.7) | |
| A reaction: The mechanism used is to assign a Gödel Number to every possible formula, so that all reasonings become instances of arithmetic. |
| 17902 | A successor is the union of a set with its singleton [George/Velleman] |
| Full Idea: For any set x, we define the 'successor' of x to be the set S(x) = x U {x}. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) | |
| A reaction: This is the Fregean approach to successor, where the Dedekind approach takes 'successor' to be a primitive. Frege 1884:§76. |
| 10133 | Frege's Theorem shows the Peano Postulates can be derived from Hume's Principle [George/Velleman] |
| Full Idea: The derivability of Peano's Postulates from Hume's Principle in second-order logic has been dubbed 'Frege's Theorem', (though Frege would not have been interested, because he didn't think Hume's Principle gave an adequate definition of numebrs). | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.8 n1) | |
| A reaction: Frege said the numbers were the sets which were the extensions of the sets created by Hume's Principle. |
| 10130 | Set theory can prove the Peano Postulates [George/Velleman] |
| Full Idea: The Peano Postulates can be proven in ZFC. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.7) |
| 10089 | Talk of 'abstract entities' is more a label for the problem than a solution to it [George/Velleman] |
| Full Idea: One might well wonder whether talk of abstract entities is less a solution to the empiricist's problem of how a priori knowledge is possible than it is a label for the problem. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Intro) | |
| A reaction: This pinpoints my view nicely. What the platonist postulates is remote, bewildering, implausible and useless! |
| 10131 | If mathematics is not about particulars, observing particulars must be irrelevant [George/Velleman] |
| Full Idea: As, in the logicist view, mathematics is about nothing particular, it is little wonder that nothing in particular needs to be observed in order to acquire mathematical knowledge. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002]) | |
| A reaction: At the very least we can say that no one would have even dreamt of the general system of arithmetic is they hadn't had experience of the particulars. Frege thought generality ensured applicability, but extreme generality might entail irrelevance. |
| 10092 | In the unramified theory of types, the types are objects, then sets of objects, sets of sets etc. [George/Velleman] |
| Full Idea: In the unramified theory of types, all objects are classified into a hierarchy of types. The lowest level has individual objects that are not sets. Next come sets whose elements are individuals, then sets of sets, etc. Variables are confined to types. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) | |
| A reaction: The objects are Type 0, the basic sets Type 1, etc. |
| 10094 | The theory of types seems to rule out harmless sets as well as paradoxical ones. [George/Velleman] |
| Full Idea: The theory of types seems to rule out harmless sets as well as paradoxical ones. If a is an individual and b is a set of individuals, then in type theory we cannot talk about the set {a,b}. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) | |
| A reaction: Since we cheerfully talk about 'Cicero and other Romans', this sounds like a rather disasterous weakness. |
| 10095 | Type theory has only finitely many items at each level, which is a problem for mathematics [George/Velleman] |
| Full Idea: A problem with type theory is that there are only finitely many individuals, and finitely many sets of individuals, and so on. The hierarchy may be infinite, but each level is finite. Mathematics required an axiom asserting infinitely many individuals. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) | |
| A reaction: Most accounts of mathematics founder when it comes to infinities. Perhaps we should just reject them? |
| 17901 | Type theory prohibits (oddly) a set containing an individual and a set of individuals [George/Velleman] |
| Full Idea: If a is an individual and b is a set of individuals, then in the theory of types we cannot talk about the set {a,b}, since it is not an individual or a set of individuals, ...but it is hard to see what harm can come from it. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.3) |
| 10114 | Bounded quantification is originally finitary, as conjunctions and disjunctions [George/Velleman] |
| Full Idea: In the first instance all bounded quantifications are finitary, for they can be viewed as abbreviations for conjunctions and disjunctions. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.6) | |
| A reaction: This strikes me as quite good support for finitism. The origin of a concept gives a good guide to what it really means (not a popular view, I admit). When Aristotle started quantifying, I suspect of he thought of lists, not totalities. |
| 10134 | Much infinite mathematics can still be justified finitely [George/Velleman] |
| Full Idea: It is possible to use finitary reasoning to justify a significant part of infinitary mathematics. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.8) | |
| A reaction: This might save Hilbert's project, by gradually accepting into the fold all the parts which have been giving a finitist justification. |
| 10123 | The intuitionists are the idealists of mathematics [George/Velleman] |
| Full Idea: The intuitionists are the idealists of mathematics. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.6) |
| 10124 | Gödel's First Theorem suggests there are truths which are independent of proof [George/Velleman] |
| Full Idea: For intuitionists, truth is not independent of proof, but this independence is precisely what seems to be suggested by Gödel's First Incompleteness Theorem. | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.8) | |
| A reaction: Thus Gödel was worse news for the Intuitionists than he was for Hilbert's Programme. Gödel himself responded by becoming a platonist about his unprovable truths. |
| 10421 | Supervenience is nowadays seen as between properties, rather than linguistic [Swoyer] |
| Full Idea: Supervenience is sometimes taken to be a relationship between two fragments of language, but it is increasingly taken to be a relationship between pairs of families of properties. | |
| From: Chris Swoyer (Properties [2000], 7.17) | |
| A reaction: If supervenience is a feature of the world, rather than of our descriptions, then it cries out for explanation, just as any other regularities do. Personally I would have thought the best explanation of the supervenience of mind and body was obvious. |
| 10410 | Anti-realists can't explain different methods to measure distance [Swoyer] |
| Full Idea: Anti-realists theories of measurement (like operationalism) cannot explain how we can use different methods to measure the same thing (e.g. lengths and distances in cosmology, geology, histology and atomic physics). | |
| From: Chris Swoyer (Properties [2000], 4.2) | |
| A reaction: Swoyer says that the explanation is that measurement aims at objective properties, the same in each of these areas. Quite good. |
| 10399 | If a property such as self-identity can only be in one thing, it can't be a universal [Swoyer] |
| Full Idea: Some properties may not be universals, if they can only be exemplified by one thing, such as 'being identical with Socrates'. | |
| From: Chris Swoyer (Properties [2000]) | |
| A reaction: I think it is absurd to think that self-identity is an intrinsic 'property', possessed by everything. That a=a is a convenience for logicians, meaning nothing in the world. And it is relational. The sharing of properties is indeed what needs explanation. |
| 10416 | Can properties have parts? [Swoyer] |
| Full Idea: Can properties have parts? | |
| From: Chris Swoyer (Properties [2000], 6.4) | |
| A reaction: If powers are more fundamental than properties, with the latter often being complexes of the underlying powers, then yes they do. But powers don't. Presumably whatever is fundamental shouldn't have parts. Why? |
| 10417 | There are only first-order properties ('red'), and none of higher-order ('coloured') [Swoyer] |
| Full Idea: 'Elementarism' is the view that there are first-order properties, but that there are no properties of any higher-order. There are first-order properties like various shades of red, but there is no higher-order property, like 'being a colour'. | |
| From: Chris Swoyer (Properties [2000], 7.1) | |
| A reaction: [He cites Bergmann 1968] Interesting. Presumably the programme is naturalistic (and hence congenial to me), and generalisations about properties are conceptual, while the properties themselves are natural. |
| 10413 | The best-known candidate for an identity condition for properties is necessary coextensiveness [Swoyer] |
| Full Idea: The best-known candidate for an identity condition for properties is necessary coextensiveness. | |
| From: Chris Swoyer (Properties [2000], 6) | |
| A reaction: The necessity (in all possible worlds) covers renates and cordates. It is hard to see how one could assert the necessity without some deeper explanation. What makes us deny that actually coextensive renates and cordates have different properties? |
| 10402 | Various attempts are made to evade universals being wholly present in different places [Swoyer] |
| Full Idea: The worry that a single thing could be wholly present in widely separated locations has led to trope theory, to the claim that properties are not located in their instances, or to the view that this treats universals as if they were individuals. | |
| From: Chris Swoyer (Properties [2000], 2.2) | |
| A reaction: I find it dispiriting to come to philosophy in the late twentieth century and have to inherit such a ridiculous view as that there are things that are 'wholly present' in many places. |
| 10400 | Conceptualism says words like 'honesty' refer to concepts, not to properties [Swoyer] |
| Full Idea: Conceptualists urge that words like 'honesty', which might seem to refer to properties, really refer to concepts. A few contemporary philosophers have defended conceptualism, and recent empirical work bears on it, but the view is no longer common. | |
| From: Chris Swoyer (Properties [2000], 1.1) | |
| A reaction: ..and that's all Swoyer says about this very interesting view! He only cites Cocchiarella 1986 Ch.3. The view leaves a lot of work to be done in explaining how nature is, and how our concepts connect to it, and arise in response to it. |
| 10403 | If properties are abstract objects, then their being abstract exemplifies being abstract [Swoyer] |
| Full Idea: If properties are abstract objects, then the property of being abstract should itself exemplify the property of being abstract. | |
| From: Chris Swoyer (Properties [2000], 2.2) | |
| A reaction: Swoyer links this observation with Plato's views on self-predication, and his Third Man Argument (which I bet originated with Aristotle in the Academy!). Do we have a regress of objects, as well as a regress of properties? |
| 10406 | One might hope to reduce possible worlds to properties [Swoyer] |
| Full Idea: One might hope to reduce possible worlds to properties. | |
| From: Chris Swoyer (Properties [2000], 4.1) | |
| A reaction: [He cites Zalta 1983 4.2, and Forrest 1986] I think we are dealing with nothing more than imagined possibilities, which are inferred from our understanding of the underlying 'powers' of the actual world (expressed as 'properties'). |
| 10404 | Extreme empiricists can hardly explain anything [Swoyer] |
| Full Idea: Extreme empiricists wind up unable to explain much of anything. | |
| From: Chris Swoyer (Properties [2000], 2.3) | |
| A reaction: This seems to be the major problem for empiricism, but I am not sure why inference to the best explanation should not be part of a sensible empirical approach. Thinking laws are just 'descriptions of regularities' illustrates the difficulty. |
| 10408 | Intensions are functions which map possible worlds to sets of things denoted by an expression [Swoyer] |
| Full Idea: Intensions are functions that assign a set to the expression at each possible world, ..so the semantic value of 'red' is the function that maps each possible world to the set of things in that world that are red. | |
| From: Chris Swoyer (Properties [2000], 4.2) | |
| A reaction: I am suddenly deeply alienated from this mathematical logicians' way of talking about what 'red' means! We need more psychology, not less. We call things red if we imagine them as looking red. Is imagination a taboo in analytical philosophy? |
| 10110 | Corresponding to every concept there is a class (some of them sets) [George/Velleman] |
| Full Idea: Corresponding to every concept there is a class (some classes will be sets, the others proper classes). | |
| From: A.George / D.J.Velleman (Philosophies of Mathematics [2002], Ch.4) |
| 10409 | Research suggests that concepts rely on typical examples [Swoyer] |
| Full Idea: Recent empirical work on concepts says that many concepts have graded membership, and stress the importance of phenomena like typicality, prototypes, and exemplars. | |
| From: Chris Swoyer (Properties [2000], 4.2) | |
| A reaction: [He cites Rorsch 1978 as the start of this] I say the mind is a database, exactly corresponding to tables, fields etc. Prototypes sound good as the way we identify a given category. Universals are the 'typical' examples labelling areas (e.g. goat). |
| 10401 | The F and G of logic cover a huge range of natural language combinations [Swoyer] |
| Full Idea: All sorts of combinations of copulas ('is') with verbs, adverbs, adjectives, determiners, common nouns, noun phrases and prepositional phrases go over into the familiar Fs and Gs of standard logical notation. | |
| From: Chris Swoyer (Properties [2000], 1.2) | |
| A reaction: This is a nice warning of how misleading logic can be when trying to understand how we think about reality. Montague semantics is an attempt to tackle the problem. Numbers as adjectives are a clear symptom of the difficulties. |
| 10420 | Maybe a proposition is just a property with all its places filled [Swoyer] |
| Full Idea: Some say we can think of a proposition as a limiting case of a property, as when the two-place property '___ loves ___' can become the zero-placed property, or proposition 'that Sam loves Darla'. | |
| From: Chris Swoyer (Properties [2000], 7.6) | |
| A reaction: If you had a prior commitment to the idea that reality largely consists of bundles of properties, I suppose you might find this tempting. |
| 22086 | The most important aspect of a human being is not reason, but passion [Kierkegaard, by Carlisle] |
| Full Idea: Kierkegaard insisted that the most important aspect of a human being is not reason, but passion. | |
| From: report of Søren Kierkegaard (works [1845]) by Clare Carlisle - Kierkegaard: a guide for the perplexed Intro | |
| A reaction: Hume comes to mind for a similar view, but in character Hume was far more rational than Kierkegaard. |
| 10412 | If laws are mere regularities, they give no grounds for future prediction [Swoyer] |
| Full Idea: If laws were mere regularities, then the fact that observed Fs have been Gs would give us no reason to conclude that those Fs we haven't encountered will also be Gs. | |
| From: Chris Swoyer (Properties [2000], 4.2) | |
| A reaction: I take this simple point to be very powerful. No amount of regularity gives grounds for asserting future patterns - one only has Humean habits. Causal mechanisms are what we are after. |
| 10411 | Two properties can have one power, and one property can have two powers [Swoyer] |
| Full Idea: If properties are identical when they confer the same capacities on their instances, different properties seem able to bestow the same powers (e.g. force), and one property can bestow different powers (attraction or repulsion). | |
| From: Chris Swoyer (Properties [2000], 4.2) | |
| A reaction: Interesting, but possibly a misunderstanding. Powers are basic, and properties are combinations of powers. A 'force' isn't a basic power, it is a consequence of various properties. Relational behaviours are also not basic powers, which are the source. |