121 ideas
| 9408 | Science studies phenomena, but only metaphysics tells us what exists [Mumford] |
| Full Idea: Science deals with the phenomena, ..but it is metaphysics, and only metaphysics, that tells us what ultimately exists. | |
| From: Stephen Mumford (Laws in Nature [2004], 01.2) |
| 9429 | Many forms of reasoning, such as extrapolation and analogy, are useful but deductively invalid [Mumford] |
| Full Idea: There are many forms of reasoning - extrapolation, interpolation, and other arguments from analogy - that are useful but deductively invalid. | |
| From: Stephen Mumford (Laws in Nature [2004], 04.4) | |
| A reaction: [He cites Molnar for this] |
| 15901 | Trying to represent curves, we study arbitrary functions, leading to the ordinals, which produces set theory [Cantor, by Lavine] |
| Full Idea: The notion of a function evolved gradually from wanting to see what curves can be represented as trigonometric series. The study of arbitrary functions led Cantor to the ordinal numbers, which led to set theory. | |
| From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite I |
| 15946 | Cantor developed sets from a progression into infinity by addition, multiplication and exponentiation [Cantor, by Lavine] |
| Full Idea: Cantor's development of set theory began with his discovery of the progression 0, 1, ....∞, ∞+1, ∞+2, ..∞x2, ∞x3, ...∞^2, ..∞^3, ...∞^∞, ...∞^∞^∞..... | |
| From: report of George Cantor (Grundlagen (Foundations of Theory of Manifolds) [1883]) by Shaughan Lavine - Understanding the Infinite VIII.2 |
| 9616 | A set is a collection into a whole of distinct objects of our intuition or thought [Cantor] |
| Full Idea: A set is any collection into a whole M of definite, distinct objects m ... of our intuition or thought. | |
| From: George Cantor (The Theory of Transfinite Numbers [1897], p.85), quoted by James Robert Brown - Philosophy of Mathematics Ch.2 | |
| A reaction: This is the original conception of a set, which hit trouble with Russell's Paradox. Cantor's original definition immediately invites thoughts about the status of vague objects. |
| 13444 | Cantor's Theorem: for any set x, its power set P(x) has more members than x [Cantor, by Hart,WD] |
| Full Idea: Cantor's Theorem says that for any set x, its power set P(x) has more members than x. | |
| From: report of George Cantor (works [1880]) by William D. Hart - The Evolution of Logic 1 |
| 18098 | Cantor proved that all sets have more subsets than they have members [Cantor, by Bostock] |
| Full Idea: Cantor's diagonalisation argument generalises to show that any set has more subsets than it has members. | |
| From: report of George Cantor (works [1880]) by David Bostock - Philosophy of Mathematics 4.5 | |
| A reaction: Thus three members will generate seven subsets. This means that 'there is no end to the series of cardinal numbers' (Bostock p.106). |
| 15505 | If a set is 'a many thought of as one', beginners should protest against singleton sets [Cantor, by Lewis] |
| Full Idea: Cantor taught that a set is 'a many, which can be thought of as one'. ...After a time the unfortunate beginner student is told that some classes - the singletons - have only a single member. Here is a just cause for student protest, if ever there was one. | |
| From: report of George Cantor (works [1880]) by David Lewis - Parts of Classes 2.1 | |
| A reaction: There is a parallel question, almost lost in the mists of time, of whether 'one' is a number. 'Zero' is obviously dubious, but if numbers are for counting, that needs units, so the unit is the precondition of counting, not part of it. |
| 10701 | Cantor showed that supposed contradictions in infinity were just a lack of clarity [Cantor, by Potter] |
| Full Idea: Cantor's theories exhibited the contradictions others had claimed to derive from the supposition of infinite sets as confusions resulting from the failure to mark the necessary distinctions with sufficient clarity. | |
| From: report of George Cantor (works [1880]) by Michael Potter - Set Theory and Its Philosophy Intro 1 |
| 10865 | The continuum is the powerset of the integers, which moves up a level [Cantor, by Clegg] |
| Full Idea: Cantor discovered that the continuum is the powerset of the integers. While adding or multiplying infinities didn't move up a level of complexity, multiplying a number by itself an infinite number of times did. | |
| From: report of George Cantor (works [1880]) by Brian Clegg - Infinity: Quest to Think the Unthinkable Ch.14 |
| 17831 | Cantor gives informal versions of ZF axioms as ways of getting from one set to another [Cantor, by Lake] |
| Full Idea: Cantor gives informal versions of the axioms of ZF as ways of getting from one set to another. | |
| From: report of George Cantor (Later Letters to Dedekind [1899]) by John Lake - Approaches to Set Theory 1.6 | |
| A reaction: Lake suggests that it should therefore be called CZF. |
| 13016 | The Axiom of Union dates from 1899, and seems fairly obvious [Cantor, by Maddy] |
| Full Idea: Cantor first stated the Union Axiom in a letter to Dedekind in 1899. It is nearly too obvious to deserve comment from most commentators. Justifications usually rest on 'limitation of size' or on the 'iterative conception'. | |
| From: report of George Cantor (works [1880]) by Penelope Maddy - Believing the Axioms I §1.3 | |
| A reaction: Surely someone can think of some way to challenge it! An opportunity to become notorious, and get invited to conferences. |
| 14199 | Cantor's sets were just collections, but Dedekind's were containers [Cantor, by Oliver/Smiley] |
| Full Idea: Cantor's definition of a set was a collection of its members into a whole, but within a few years Dedekind had the idea of a set as a container, enclosing its members like a sack. | |
| From: report of George Cantor (works [1880]) by Oliver,A/Smiley,T - What are Sets and What are they For? Intro | |
| A reaction: As the article goes on to show, these two view don't seem significantly different until you start to ask about the status of the null set and of singletons. I intuitively vote for Dedekind. Set theory is the study of brackets. |
| 10082 | There are infinite sets that are not enumerable [Cantor, by Smith,P] |
| Full Idea: Cantor's Theorem (1874) says there are infinite sets that are not enumerable. This is proved by his 1891 'diagonal argument'. | |
| From: report of George Cantor (works [1880]) by Peter Smith - Intro to Gödel's Theorems 2.3 | |
| A reaction: [Smith summarises the diagonal argument] |
| 13483 | Cantor's Paradox: the power set of the universe must be bigger than the universe, yet a subset of it [Cantor, by Hart,WD] |
| Full Idea: The problem of Cantor's Paradox is that the power set of the universe has to be both bigger than the universe (by Cantor's theorem) and not bigger (since it is a subset of the universe). | |
| From: report of George Cantor (works [1880]) by William D. Hart - The Evolution of Logic 3 | |
| A reaction: Russell eliminates the 'universe' in his theory of types. I don't see why you can't just say that the members of the set are hypothetical rather than real, and that hypothetically the universe might contain more things than it does. |
| 8710 | The powerset of all the cardinal numbers is required to be greater than itself [Cantor, by Friend] |
| Full Idea: Cantor's Paradox says that the powerset of a set has a cardinal number strictly greater than the original set, but that means that the powerset of the set of all the cardinal numbers is greater than itself. | |
| From: report of George Cantor (works [1880]) by Michèle Friend - Introducing the Philosophy of Mathematics | |
| A reaction: Friend cites this with the Burali-Forti paradox and the Russell paradox as the best examples of the problems of set theory in the early twentieth century. Did this mean that sets misdescribe reality, or that we had constructed them wrongly? |
| 15910 | Cantor named the third realm between the finite and the Absolute the 'transfinite' [Cantor, by Lavine] |
| Full Idea: Cantor believed he had discovered that between the finite and the 'Absolute', which is 'incomprehensible to the human understanding', there is a third category, which he called 'the transfinite'. | |
| From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite III.4 |
| 15905 | Cantor proved the points on a plane are in one-to-one correspondence to the points on a line [Cantor, by Lavine] |
| Full Idea: In 1878 Cantor published the unexpected result that one can put the points on a plane, or indeed any n-dimensional space, into one-to-one correspondence with the points on a line. | |
| From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite III.1 |
| 9983 | Cantor took the ordinal numbers to be primary [Cantor, by Tait] |
| Full Idea: Cantor took the ordinal numbers to be primary: in his generalization of the cardinals and ordinals into the transfinite, it is the ordinals that he calls 'numbers'. | |
| From: report of George Cantor (works [1880]) by William W. Tait - Frege versus Cantor and Dedekind VI | |
| A reaction: [Tait says Dedekind also favours the ordinals] It is unclear how the matter might be settled. Humans cannot give the cardinality of large groups without counting up through the ordinals. A cardinal gets its meaning from its place in the ordinals? |
| 17798 | Cantor presented the totality of natural numbers as finite, not infinite [Cantor, by Mayberry] |
| Full Idea: Cantor taught us to regard the totality of natural numbers, which was formerly thought to be infinite, as really finite after all. | |
| From: report of George Cantor (works [1880]) by John Mayberry - What Required for Foundation for Maths? p.414-2 | |
| A reaction: I presume this is because they are (by definition) countable. |
| 9971 | Cantor introduced the distinction between cardinals and ordinals [Cantor, by Tait] |
| Full Idea: Cantor introduced the distinction between cardinal and ordinal numbers. | |
| From: report of George Cantor (works [1880]) by William W. Tait - Frege versus Cantor and Dedekind Intro | |
| A reaction: This seems remarkably late for what looks like a very significant clarification. The two concepts coincide in finite cases, but come apart in infinite cases (Tait p.58). |
| 9892 | Cantor showed that ordinals are more basic than cardinals [Cantor, by Dummett] |
| Full Idea: Cantor's work revealed that the notion of an ordinal number is more fundamental than that of a cardinal number. | |
| From: report of George Cantor (works [1880]) by Michael Dummett - Frege philosophy of mathematics Ch.23 | |
| A reaction: Dummett makes it sound like a proof, which I find hard to believe. Is the notion that I have 'more' sheep than you logically prior to how many sheep we have? If I have one more, that implies the next number, whatever that number may be. Hm. |
| 15911 | Ordinals are generated by endless succession, followed by a limit ordinal [Cantor, by Lavine] |
| Full Idea: Ordinal numbers are generated by two principles: each ordinal has an immediate successor, and each unending sequence has an ordinal number as its limit (that is, an ordinal that is next after such a sequence). | |
| From: report of George Cantor (Grundlagen (Foundations of Theory of Manifolds) [1883]) by Shaughan Lavine - Understanding the Infinite III.4 |
| 14136 | A cardinal is an abstraction, from the nature of a set's elements, and from their order [Cantor] |
| Full Idea: The cardinal number of M is the general idea which, by means of our active faculty of thought, is deduced from the collection M, by abstracting from the nature of its diverse elements and from the order in which they are given. | |
| From: George Cantor (works [1880]), quoted by Bertrand Russell - The Principles of Mathematics §284 | |
| A reaction: [Russell cites 'Math. Annalen, XLVI, §1'] See Fine 1998 on this. |
| 15906 | Cantor tried to prove points on a line matched naturals or reals - but nothing in between [Cantor, by Lavine] |
| Full Idea: Cantor said he could show that every infinite set of points on the line could be placed into one-to-one correspondence with either the natural numbers or the real numbers - with no intermediate possibilies (the Continuum hypothesis). His proof failed. | |
| From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite III.1 |
| 11015 | Cantor's diagonal argument proved you can't list all decimal numbers between 0 and 1 [Cantor, by Read] |
| Full Idea: Cantor's diagonal argument showed that all the infinite decimals between 0 and 1 cannot be written down even in a single never-ending list. | |
| From: report of George Cantor (works [1880]) by Stephen Read - Thinking About Logic Ch.6 |
| 15903 | A real is associated with an infinite set of infinite Cauchy sequences of rationals [Cantor, by Lavine] |
| Full Idea: Cantor's theory of Cauchy sequences defines a real number to be associated with an infinite set of infinite sequences of rational numbers. | |
| From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite II.6 | |
| A reaction: This sounds remarkably like the endless decimals we use when we try to write down an actual real number. |
| 18251 | Irrational numbers are the limits of Cauchy sequences of rational numbers [Cantor, by Lavine] |
| Full Idea: Cantor introduced irrationals to play the role of limits of Cauchy sequences of rational numbers. | |
| From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite 4.2 |
| 15902 | Irrationals and the Dedekind Cut implied infinite classes, but they seemed to have logical difficulties [Cantor, by Lavine] |
| Full Idea: From the very nature of an irrational number, it seems necessary to understand the mathematical infinite thoroughly before an adequate theory of irrationals is possible. Infinite classes are obvious in the Dedekind Cut, but have logical difficulties | |
| From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite II Intro | |
| A reaction: Almost the whole theory of analysis (calculus) rested on the irrationals, so a theory of the infinite was suddenly (in the 1870s) vital for mathematics. Cantor wasn't just being eccentric or mystical. |
| 15908 | It was Cantor's diagonal argument which revealed infinities greater than that of the real numbers [Cantor, by Lavine] |
| Full Idea: Cantor's 1891 diagonal argument revealed there are infinitely many infinite powers. Indeed, it showed more: it shows that given any set there is another of greater power. Hence there is an infinite power strictly greater than that of the set of the reals. | |
| From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite III.2 |
| 13464 | Cantor proposes that there won't be a potential infinity if there is no actual infinity [Cantor, by Hart,WD] |
| Full Idea: What we might call 'Cantor's Thesis' is that there won't be a potential infinity of any sort unless there is an actual infinity of some sort. | |
| From: report of George Cantor (works [1880]) by William D. Hart - The Evolution of Logic 1 | |
| A reaction: This idea is nicely calculated to stop Aristotle in his tracks. |
| 10112 | The naturals won't map onto the reals, so there are different sizes of infinity [Cantor, by George/Velleman] |
| Full Idea: Cantor showed that the complete totality of natural numbers cannot be mapped 1-1 onto the complete totality of the real numbers - so there are different sizes of infinity. | |
| From: report of George Cantor (works [1880]) by A.George / D.J.Velleman - Philosophies of Mathematics Ch.4 |
| 15896 | Cantor needed Power Set for the reals, but then couldn't count the new collections [Cantor, by Lavine] |
| Full Idea: Cantor grafted the Power Set axiom onto his theory when he needed it to incorporate the real numbers, ...but his theory was supposed to be theory of collections that can be counted, but he didn't know how to count the new collections. | |
| From: report of George Cantor (The Theory of Transfinite Numbers [1897]) by Shaughan Lavine - Understanding the Infinite I | |
| A reaction: I take this to refer to the countability of the sets, rather than the members of the sets. Lavine notes that counting was Cantor's key principle, but he now had to abandon it. Zermelo came to the rescue. |
| 17889 | CH: An infinite set of reals corresponds 1-1 either to the naturals or to the reals [Cantor, by Koellner] |
| Full Idea: Cantor's Continuum Hypothesis (CH) says that for every infinite set X of reals there is either a one-to-one correspondence between X and the natural numbers, or between X and the real numbers. | |
| From: report of George Cantor (works [1880]) by Peter Koellner - On the Question of Absolute Undecidability 1.2 | |
| A reaction: Every single writer I read defines this differently, which drives me crazy, but is also helpfully illuminating. There is a moral there somewhere. |
| 13447 | Cantor: there is no size between naturals and reals, or between a set and its power set [Cantor, by Hart,WD] |
| Full Idea: Cantor conjectured that there is no size between those of the naturals and the reals - called the 'continuum hypothesis'. The generalized version says that for no infinite set A is there a set larger than A but smaller than P(A). | |
| From: report of George Cantor (works [1880]) by William D. Hart - The Evolution of Logic 1 | |
| A reaction: Thus there are gaps between infinite numbers, and the power set is the next size up from any infinity. Much discussion as ensued about whether these two can be proved. |
| 10883 | Cantor's Continuum Hypothesis says there is a gap between the natural and the real numbers [Cantor, by Horsten] |
| Full Idea: Cantor's Continuum Hypothesis states that there are no sets which are too large for there to be a one-to-one correspondence between the set and the natural numbers, but too small for there to exist a one-to-one correspondence with the real numbers. | |
| From: report of George Cantor (works [1880]) by Leon Horsten - Philosophy of Mathematics §5.1 |
| 8733 | The Continuum Hypothesis says there are no sets between the natural numbers and reals [Cantor, by Shapiro] |
| Full Idea: Cantor's 'continuum hypothesis' is the assertion that there are no infinite cardinalities strictly between the size of the natural numbers and the size of the real numbers. | |
| From: report of George Cantor (works [1880]) by Stewart Shapiro - Thinking About Mathematics 2.4 | |
| A reaction: The tricky question is whether this hypothesis can be proved. |
| 13528 | Continuum Hypothesis: there are no sets between N and P(N) [Cantor, by Wolf,RS] |
| Full Idea: Cantor's conjecture (the Continuum Hypothesis) is that there are no sets between N and P(N). The 'generalized' version replaces N with an arbitrary infinite set. | |
| From: report of George Cantor (works [1880]) by Robert S. Wolf - A Tour through Mathematical Logic 2.2 | |
| A reaction: The initial impression is that there is a single gap in the numbers, like a hole in ozone layer, but the generalised version implies an infinity of gaps. How can there be gaps in the numbers? Weird. |
| 9555 | Continuum Hypothesis: no cardinal greater than aleph-null but less than cardinality of the continuum [Cantor, by Chihara] |
| Full Idea: Cantor's Continuum Hypothesis was that there is no cardinal number greater than aleph-null but less than the cardinality of the continuum. | |
| From: report of George Cantor (works [1880]) by Charles Chihara - A Structural Account of Mathematics 05.1 | |
| A reaction: I have no view on this (have you?), but the proposal that there are gaps in the number sequences has to excite all philosophers. |
| 15893 | Cantor's theory concerns collections which can be counted, using the ordinals [Cantor, by Lavine] |
| Full Idea: Cantor's set theory was not of collections in some familiar sense, but of collections that can be counted using the indexes - the finite and transfinite ordinal numbers. ..He treated infinite collections as if they were finite. | |
| From: report of George Cantor (works [1880]) by Shaughan Lavine - Understanding the Infinite I |
| 18174 | Cantor extended ordinals into the transfinite, and they can thus measure infinite cardinalities [Cantor, by Maddy] |
| Full Idea: Cantor's second innovation was to extend the sequence of ordinal numbers into the transfinite, forming a handy scale for measuring infinite cardinalities. | |
| From: report of George Cantor (works [1880]) by Penelope Maddy - Naturalism in Mathematics I.1 | |
| A reaction: Struggling with this. The ordinals seem to locate the cardinals, but in what sense do they 'measure' them? |
| 18173 | Cardinality strictly concerns one-one correspondence, to test infinite sameness of size [Cantor, by Maddy] |
| Full Idea: Cantor's first innovation was to treat cardinality as strictly a matter of one-to-one correspondence, so that the question of whether two infinite sets are or aren't of the same size suddenly makes sense. | |
| From: report of George Cantor (works [1880]) by Penelope Maddy - Naturalism in Mathematics I.1 | |
| A reaction: It makes sense, except that all sets which are infinite but countable can be put into one-to-one correspondence with one another. What's that all about, then? |
| 9992 | The 'extension of a concept' in general may be quantitatively completely indeterminate [Cantor] |
| Full Idea: The author entirely overlooks the fact that the 'extension of a concept' in general may be quantitatively completely indeterminate. Only in certain cases is the 'extension of a concept' quantitatively determinate. | |
| From: George Cantor (Review of Frege's 'Grundlagen' [1885], 1932:440), quoted by William W. Tait - Frege versus Cantor and Dedekind | |
| A reaction: Cantor presumably has in mind various infinite sets. Tait is drawing our attention to the fact that this objection long precedes Russell's paradox, which made the objection more formal (a language Frege could understand!). |
| 10232 | Property extensions outstrip objects, so shortage of objects caused the Caesar problem [Cantor, by Shapiro] |
| Full Idea: Cantor's theorem entails that there are more property extensions than objects. So there are not enough objects in any domain to serve as extensions for that domain. So Frege's view that numbers are objects led to the Caesar problem. | |
| From: report of George Cantor (works [1880]) by Stewart Shapiro - Philosophy of Mathematics 4.6 | |
| A reaction: So the possibility that Caesar might have to be a number arises because otherwise we are threatening to run out of numbers? Is that really the problem? |
| 18176 | Pure mathematics is pure set theory [Cantor] |
| Full Idea: Pure mathematics ...according to my conception is nothing other than pure set theory. | |
| From: George Cantor (works [1880], I.1), quoted by Penelope Maddy - Naturalism in Mathematics I.1 | |
| A reaction: [an unpublished paper of 1884] So right at the beginning of set theory this claim was being made, before it was axiomatised, and so on. Zermelo endorsed the view, and it flourished unchallenged until Benacerraf (1965). |
| 8631 | Cantor says that maths originates only by abstraction from objects [Cantor, by Frege] |
| Full Idea: Cantor calls mathematics an empirical science in so far as it begins with consideration of things in the external world; on his view, number originates only by abstraction from objects. | |
| From: report of George Cantor (works [1880]) by Gottlob Frege - Grundlagen der Arithmetik (Foundations) §21 | |
| A reaction: Frege utterly opposed this view, and he seems to have won the day, but I am rather thrilled to find the great Cantor endorsing my own intuitions on the subject. The difficulty is to explain 'abstraction'. |
| 9427 | For Humeans the world is a world primarily of events [Mumford] |
| Full Idea: For Humeans the world is a world primarily of events. | |
| From: Stephen Mumford (Laws in Nature [2004], 03.6) |
| 14334 | Modest realism says there is a reality; the presumptuous view says we can accurately describe it [Mumford] |
| Full Idea: The claim of modest realism is that there is a subject-independent reality; the presumptuous claim is that we are capable of describing that reality accurately. | |
| From: Stephen Mumford (Dispositions [1998], 09.1) | |
| A reaction: And the super-presumptuous claim is that there only exists one ultimate accurate description of reality. I am happy to call myself a Modest Realist on this one. |
| 14306 | Anti-realists deny truth-values to all statements, and say evidence and ontology are inseparable [Mumford] |
| Full Idea: The anti-realist declines to permit that all statements have truth-values. ...The essence of the anti-realist position is that evidence and ontology cannot be separated. | |
| From: Stephen Mumford (Dispositions [1998], 03.6) | |
| A reaction: [second half on p.51] The idea that evidence and ontology are 'inseparable' strikes me as an absurd idea. The proposal that you should not speculate about ontology without some sort of evidence is, of course, not unreasonable. |
| 14333 | Dispositions and categorical properties are two modes of presentation of the same thing [Mumford] |
| Full Idea: The dispositional and the categorical are correctly understood just as two modes of presentation of the same instantiated properties. | |
| From: Stephen Mumford (Dispositions [1998], 08.6) | |
| A reaction: This is Mumford's own conclusion, after discussing the views of Armstrong. How about 'a disposition is the modal profile' of a categorical property? |
| 14336 | Categorical predicates are those unconnected to functions [Mumford] |
| Full Idea: A predicate which is conceptually connected to no function ... is a categorical predicate. | |
| From: Stephen Mumford (Dispositions [1998], 09.7) | |
| A reaction: This is an expansion of Mumford's own theory of dispositions, as functional. Does a cork in a wine bottle have a function, but without doing anything? It seems to achieve its function purely through its structure. |
| 14315 | Categorical properties and dispositions appear to explain one another [Mumford] |
| Full Idea: Though categorical properties provide explanations for dispositions, categorical properties are also explained by dispositions; hence neither category uniquely explains the other. | |
| From: Stephen Mumford (Dispositions [1998], 05.3) | |
| A reaction: The conclusion doesn't seem to follow. It depends which one is found at the bottom level. It can go up from a basic disposition, to a categorical property, to another disposition - or the other way around. |
| 14332 | There are four reasons for seeing categorical properties as the most fundamental [Mumford] |
| Full Idea: Four reasons for reducing everything to the categorical are: categorical predicates have wider scope; dispositions are variably realised by the categorical; categorical is 1st order, dispositions 2nd; categorical properties are explanatorily basic. | |
| From: Stephen Mumford (Dispositions [1998], 08.5) | |
| A reaction: I particularly reject the fourth reason, as I take categorical properties as still in need of explanation. The categorical view is contingent (and Humean), but I take the categorical properties to be necessitated by the underlying powers. |
| 14302 | A lead molecule is not leaden, and macroscopic properties need not be microscopically present [Mumford] |
| Full Idea: Though lead is said to be composed of molecules of lead, these molecules are not leaden in the everyday sense of the word. This suggests that a property need not be present at the microscopic level in order to be present at the macroscopic level. | |
| From: Stephen Mumford (Dispositions [1998], 02.3) | |
| A reaction: [He quotes Joske] This strikes me as a key principle to grasp about properties. One H2O molecule is not water, any more than a brick is a house! Nearly all properties (or all?) are 'emergent' (in the sensible, non-mystical use of that word). |
| 16643 | Accidents always remain suited to a subject [Bonaventura] |
| Full Idea: An accident's aptitudinal relationship to a subject is essential, and this is never taken away from accidents….for it is true to say that they are suited to a subject. | |
| From: Bonaventura (Commentary on Sentences [1252], IV.12.1.1.1c) | |
| A reaction: This is the compromise view that allows accidents to be separated, for Transubstantiation, while acknowledging that we identify them with their subjects. |
| 14294 | Dispositions are attacked as mere regularities of events, or place-holders for unknown properties [Mumford] |
| Full Idea: Dispositions are attacked as either just saying how something will behave (logical fictions about regularities of events), or as primitive pre-scientific terms like 'phlogiston', place-holders used when we are ignorant of real properties. | |
| From: Stephen Mumford (Dispositions [1998], 01.1) | |
| A reaction: [compressed] The first view he calls the Ryle-Wittgenstein view, which seems to track back to Hume. |
| 9446 | Properties are just natural clusters of powers [Mumford] |
| Full Idea: The view of properties I find most attractive is one in which they are natural clusters of, and exhausted by, powers (plus other connections to other properties). | |
| From: Stephen Mumford (Laws in Nature [2004], 10.6) |
| 14316 | If dispositions have several categorical realisations, that makes the two separate [Mumford] |
| Full Idea: We might claim that dispositions are variably realized by a number of categorical bases; therefore they must be distinct from those bases. | |
| From: Stephen Mumford (Dispositions [1998], 05.4) | |
| A reaction: Cars can be realised by a variety of models, therefore models are not cars? This might work if dispositions are only characterised functionally, as Mumford proposes, but I'm not convinced. |
| 14310 | Dispositions are classifications of properties by functional role [Mumford] |
| Full Idea: A dispositional property is the classification of a property according to its functional role....[p.85] What is essential to a disposition - its identity condition - is its functional role. | |
| From: Stephen Mumford (Dispositions [1998], 04.5) | |
| A reaction: This is Mumford's view of dispositions. I am wary of any proposal to define something according to its role, because it must have an intrinsic nature which equips it to have that role. |
| 14317 | I say the categorical base causes the disposition manifestation [Mumford] |
| Full Idea: The view I promote is one where the categorical base is a cause of the disposition manifestation. | |
| From: Stephen Mumford (Dispositions [1998], 05.5) | |
| A reaction: It seems to me (I think) that the most basic thing has to be a power, whose nature is intrinsically beyond our grasp, and that categorical properties are the result of these powers. Powers are dispositional in character. |
| 14313 | All properties must be causal powers (since they wouldn't exist otherwise) [Mumford] |
| Full Idea: It seems that every property must be a causal power, since every property must be causally potent (as a necessary condition of its very existence). | |
| From: Stephen Mumford (Dispositions [1998], 04.7) | |
| A reaction: Mumford cautiously endorses this idea, which seems to rest on the thesis that 'to exist is to have causal powers'. I think I am even keener on it than Mumford is. Powers and properties need to be disentangled, however. |
| 14318 | Intrinsic properties are just causal powers, and identifying a property as causal is then analytic [Mumford] |
| Full Idea: Understanding intrinsic properties as being causal powers is likely to be most profitable, and, if true, renders the causal criterion of property existence true analytically. | |
| From: Stephen Mumford (Dispositions [1998], 06.2) | |
| A reaction: [He cites E.Fales on this] I'm inclined to think that in the ultimate ontology the notion of a 'property' drops out. There are true causal powers, and then conventional human ways of grouping such powers together and naming them. |
| 14293 | Dispositions are ascribed to at least objects, substances and persons [Mumford] |
| Full Idea: Dispositions are ascribed to at least three distinguishable classes of things: objects, substances, and persons. | |
| From: Stephen Mumford (Dispositions [1998], 01.1) | |
| A reaction: Are dispositions not also ascribed to properties? Magnetism has a disposition to attract iron filings? |
| 14326 | Unlike categorical bases, dispositions necessarily occupy a particular causal role [Mumford] |
| Full Idea: The idea of a disposition occupying a different causal role involves a conceptual confusion, ...but there is no conceptual or logical absurdity in a categorical base occupying a different causal role. | |
| From: Stephen Mumford (Dispositions [1998], 07.3) | |
| A reaction: This is the core of Mumford's theory of dispositions. I'm beginning to think that dispositions are merely ways we have of describing and labelling functional mechanisms, and so 'dispositions' drop out of the final story. |
| 14298 | Dispositions can be contrasted either with occurrences, or with categorical properties [Mumford] |
| Full Idea: For some the notion of a disposition is contrasted with the notion of an occurrence; for others, it is contrasted with that of a categorical property. | |
| From: Stephen Mumford (Dispositions [1998], 01.6) | |
| A reaction: I vote for dispositions over the other two, but I take the categorical properties to be the main rival. |
| 14314 | If dispositions are powers, background conditions makes it hard to say what they do [Mumford] |
| Full Idea: The realist says that disposition ascriptions are ascriptions of real powers. This leaves unanswered the question, 'power to do what?' The problem of background conditions means that the realist cannot say what it is that a power is a power to do. | |
| From: Stephen Mumford (Dispositions [1998], 04.9) | |
| A reaction: It is hard to say what a disposition will do, under any other account of dispositions. I would take a power to be defined by a 'modal profile', rather than an actual account of what it will lead to. |
| 14325 | Maybe dispositions can replace powers in metaphysics, as what induces property change [Mumford] |
| Full Idea: Dispositions can regain the metaphysical role traditionally ascribed to real powers: the that-in-virtue-of-which-something-will-G, if F. | |
| From: Stephen Mumford (Dispositions [1998], 06.9) | |
| A reaction: The attraction is that dispositions can be specified a little more clearly (especially in Mumford's functional version) whereas there may be no more to say about a power once it has been located and named. |
| 14312 | Orthodoxy says dispositions entail conditionals (rather than being equivalent to them) [Mumford] |
| Full Idea: The orthodox realist view has it that what makes an ascription a disposition ascription is not that it is equivalent to a conditional proposition but that it entails one. | |
| From: Stephen Mumford (Dispositions [1998], 04.7) | |
| A reaction: Mumford says that Martin has shown that dispositions need not entail conditionals (when a 'fink' is operating, something which intervenes between disposition and outcome). |
| 14291 | Dispositions are not just possibilities - they are features of actual things [Mumford] |
| Full Idea: Dispositions should correctly be understood as more than mere possibilities. To say something has a disposition is to say something about how it is actually. | |
| From: Stephen Mumford (Dispositions [1998], Pref) | |
| A reaction: To me this is a basic axiom of metaphysics. The word 'power' serves well for the actual embodiment of a disposition. A power gives rise to one or more dispositions. Or one or more powers give rise to a disposition? |
| 14299 | There could be dispositions that are never manifested [Mumford] |
| Full Idea: It seems plausible that a disposition could be possessed though no manifestation events occur. | |
| From: Stephen Mumford (Dispositions [1998], 01.6) | |
| A reaction: It is more than 'plausible' - it is screamingly obvious to everybody, apart from a few philosophers. "Some mute inglorious Milton here may rest" (Gray's Elegy). |
| 14323 | If every event has a cause, it is easy to invent a power to explain each case [Mumford] |
| Full Idea: Given any event, and the assumption that every event has a cause, then some power can always be invented as the cause of that event. | |
| From: Stephen Mumford (Dispositions [1998], 06.6) | |
| A reaction: This is a useful warning, and probably explains why 'powers' fell out of fashion in scientifice theorising. They seem to make a return, though, as an appropriate term for the bottom level of each of our explanations. |
| 14328 | Traditional powers initiate change, but are mysterious between those changes [Mumford] |
| Full Idea: In the old-fashioned sense, 'powers' are real potentialities that initiate changes but seem to have a mysterious existence in between those changes. | |
| From: Stephen Mumford (Dispositions [1998], 07.10) | |
| A reaction: What is a person when they are asleep? What is a dishwasher when it isn't running? What is gunpowder when it doesn't explode? We all understand latent powers. To see them as a 'mystery' is to want to know too much. |
| 14331 | Categorical eliminativists say there are no dispositions, just categorical states or mechanisms [Mumford] |
| Full Idea: The categorical eliminativist claims that there are no dispositional properties. All properties must be conceived of as categorical states or mechanisms, in the spirit of Boyle's explanation of powers. | |
| From: Stephen Mumford (Dispositions [1998], 08.3A) | |
| A reaction: What is the difference between a structure and a mechanism? How do we distinguish an active from an inactive mechanism? Without powers or dispositions, nature is dead junk. |
| 9435 | A 'porridge' nominalist thinks we just divide reality in any way that suits us [Mumford] |
| Full Idea: A 'porridge' nominalist denies natural kinds, and thinks there are no objective divisions in reality, so concepts or words can be used by a community to divide the world up in any way that suits their purposes. | |
| From: Stephen Mumford (Laws in Nature [2004], 07.3) |
| 9447 | If properties are clusters of powers, this can explain why properties resemble in degrees [Mumford] |
| Full Idea: If a cluster of ten powers exhausts property F, and property G differs in respect of just one power, this might explain why properties can resemble other properties and in different degrees. | |
| From: Stephen Mumford (Laws in Nature [2004], 10.6) | |
| A reaction: I love this. The most intractable problem about properties and universals is that of abstract reference - pink resembles red more than pink resembles green. If colours are clusters of powers, red and pink share nine out of ten of them. |
| 18617 | Substances, unlike aggregates, can survive a change of parts [Mumford] |
| Full Idea: Substances can survive a change in their parts in a way that a mere aggregate of parts. | |
| From: Stephen Mumford (Metaphysics: a very short introduction [2012], 3) | |
| A reaction: A simple but very important idea. If we then distinguish between 'substances' and 'aggregates' we get a much clearer grip on things. Is the Ship of Theseus a substance or an aggregate? There is no factual answer to that. What do you want to explain? |
| 14295 | Many artefacts have dispositional essences, which make them what they are [Mumford] |
| Full Idea: Thermostats, thermometers, axes, spoons, and batteries have dispositional essences, which make them what they are. | |
| From: Stephen Mumford (Dispositions [1998], 01.2 iv) | |
| A reaction: I would have thought that we could extend this proposal well beyond artefacts, but it certainly seems particularly clear in artefacts, where a human intention seems to be inescapably involved. |
| 12248 | How can we show that a universally possessed property is an essential property? [Mumford] |
| Full Idea: Essentialists fail to show how we ascend from being a property universally possessed, by all kind members, to the status of being an essential property. | |
| From: Stephen Mumford (Laws in Nature [2004], 07.5) | |
| A reaction: This is precisely where my proposal comes in - the essential properties, as opposed to the accidentaly universals, are those which explain the nature and behaviour of each kind of thing (and each individual thing). |
| 16696 | Successive things reduce to permanent things [Bonaventura] |
| Full Idea: Everything successive reduces to something permanent. | |
| From: Bonaventura (Commentary on Sentences [1252], II.2.1.1.3 ad 5), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 18.2 | |
| A reaction: Avicenna first took successive entities seriously, but Bonaventure and Aquinas seem to have rejected them, or given reductive accounts of them. It resembles modern actualists versus modal realists. |
| 18618 | Maybe possibilities are recombinations of the existing elements of reality [Mumford] |
| Full Idea: It has been suggested that we could think of possibilities as recombinations of all the existing elements of reality. | |
| From: Stephen Mumford (Metaphysics: a very short introduction [2012], 8) | |
| A reaction: [Armstrong 1989 is the source] The obvious problem would be that the existence of an entirely different reality would be impossible, if this was all possibility could be. It seems to cramp the style of the possible too much. Are properties elements? |
| 18619 | Combinatorial possibility has to allow all elements to be combinable, which seems unlikely [Mumford] |
| Full Idea: The combinatorial account only works if you allow that the elements are recombinable. ...But could Lincoln really have been green? It seems possible that you could jump to the moon, unless we impose some restrictions. | |
| From: Stephen Mumford (Metaphysics: a very short introduction [2012], 8) | |
| A reaction: Mumford suggests different combination rules for logical and natural possibility. The general objection is that combinatorial possibility is too permissive - which it clearly is. |
| 18620 | Combinatorial possibility relies on what actually exists (even over time), but there could be more [Mumford] |
| Full Idea: Can combinatorial possibility deliver enough possibilities? It uses the existing elements, but there might have been one more particular or one more property. Even extended over time, the elements seem finite, yet there could have been more. | |
| From: Stephen Mumford (Metaphysics: a very short introduction [2012], 8) | |
| A reaction: [compressed] One objection is that the theory allows too much, and now the objection is that it allows too little. Both objections are correct, so that's the end of that. But I admire the attempt to base modality on actuality. |
| 14309 | Truth-functional conditionals can't distinguish whether they are causal or accidental [Mumford] |
| Full Idea: If a conditional remains truth-functional it is incapable of expressing the fact that the connection between antecedent and consequent in the conditional is a causal one rather than merely accidental | |
| From: Stephen Mumford (Dispositions [1998], 03.8) | |
| A reaction: This is the first step towards an account of conditionals which will work in real life rather than merely in classical logic. |
| 14311 | Dispositions are not equivalent to stronger-than-material conditionals [Mumford] |
| Full Idea: The conclusion that disposition ascriptions are not equivalent to stronger-than-material conditionals is largely to be accepted. | |
| From: Stephen Mumford (Dispositions [1998], 04.7) | |
| A reaction: [he attributes the view to C.B.Martin 1994] It is hard to see how to describe a disposition in anything other than conditional terms. Mumford's 'functional role' probably has to be described conditionally. It is how the conditional cashes out. |
| 14319 | Nomothetic explanations cite laws, and structural explanations cite mechanisms [Mumford] |
| Full Idea: A nomothetic explanation appeals to laws where the explanandum is shown to be an instance of a general law. ...The alternative is a structural explanation, which postulates a mechanism, opening up a hidden world. | |
| From: Stephen Mumford (Dispositions [1998], 06.4) | |
| A reaction: [He cites E.McMullin 1978] I am very much in favour of structural explanations, and opposed to nomothetic ones. That is, nomothetic accounts are only the first step towards an explanation - perhaps a mere identification of the explanandum. |
| 14342 | General laws depend upon the capacities of particulars, not the other way around [Mumford] |
| Full Idea: Laws, qua true generalities, if they exist at all, are ontologically parasitic upon the capacities of particulars, rather than the other way round. | |
| From: Stephen Mumford (Dispositions [1998], 10.6) | |
| A reaction: Quite so. And hence trying to explain a particular behaviour by saying that it falls under a law is absurdly circular and vacuous. |
| 14322 | If fragile just means 'breaks when dropped', it won't explain a breakage [Mumford] |
| Full Idea: If fragile means nothing more than 'breaks when dropped', then it is no explanation of why something breaks when dropped. | |
| From: Stephen Mumford (Dispositions [1998], 06.5) | |
| A reaction: His point is that you have to unpack the notion of fragile, which presumably cites underlying mechanisms. This is the 'virtus dormitiva' problem - but that explanation of opium's dormitive powers is not entirely stupid. |
| 14337 | Maybe dispositions can replace the 'laws of nature' as the basis of explanation [Mumford] |
| Full Idea: I will consider the case for an ontology of real dispositions replacing the so-called laws of nature as the basic building blocks of explanation. | |
| From: Stephen Mumford (Dispositions [1998], 10.1) | |
| A reaction: This precisely summarises the view I am exploring, with a particular focus on real essences. I certainly think the 'laws of nature' must go. See Mumford's second book on this. |
| 14343 | To avoid a regress in explanations, ungrounded dispositions will always have to be posited [Mumford] |
| Full Idea: The nature of explanation is such that ungrounded dispositions will always have to be posited in order to avoid a regress of explanation. | |
| From: Stephen Mumford (Dispositions [1998], 10.6) | |
| A reaction: This seems to be right, but leaves it open to mock the proposals as 'virtus dormitiva' - empty place-holders that ground explanations but do no explanatory work. What else can be done, though? |
| 14320 | Subatomic particles may terminate explanation, if they lack structure [Mumford] |
| Full Idea: The behaviour of subatomic particles cannot be further analysed into structures and this may tempt us to regard these as instances of 'brute' ungrounded dispositions which end any possible regress of explanation. | |
| From: Stephen Mumford (Dispositions [1998], 06.4) | |
| A reaction: This seems right, if it is 'structural' explanations we are after (as I think we are) which look for mechanisms. An electron seems to be just three dispositions and no structure, so there is nothing more to say. Ladyman scorns this account. |
| 14324 | Ontology is unrelated to explanation, which concerns modes of presentation and states of knowledge [Mumford] |
| Full Idea: Nothing about ontology is at stake in questions of explanation, for explanatory success is contingent upon the modes of presentation of explanans and explananda, and relative states of knowledge and ignorance. | |
| From: Stephen Mumford (Dispositions [1998], 06.8) | |
| A reaction: There are real facts about the immediate and unusual causes which immediately precede an event, and these might be candidates for a real explanation. There are also real mechanisms and powers which dictate a things behaviour. |
| 8715 | Infinities expand the bounds of the conceivable; we explore concepts to explore conceivability [Cantor, by Friend] |
| Full Idea: Cantor (in his exploration of infinities) pushed the bounds of conceivability further than anyone before him. To discover what is conceivable, we have to enquire into the concept. | |
| From: report of George Cantor (works [1880]) by Michèle Friend - Introducing the Philosophy of Mathematics 6.5 | |
| A reaction: This remark comes during a discussion of Husserl's phenomenology. Intuitionists challenge Cantor's claim, and restrict what is conceivable to what is provable. Does possibility depend on conceivability? |
| 13454 | Cantor says (vaguely) that we abstract numbers from equal sized sets [Hart,WD on Cantor] |
| Full Idea: Cantor thought that we abstract a number as something common to all and only those sets any one of which has as many members as any other. ...However one wants to see the logic of the inference. The irony is that set theory lays out this logic. | |
| From: comment on George Cantor (works [1880]) by William D. Hart - The Evolution of Logic 1 | |
| A reaction: The logic Hart has in mind is the notion of an equivalence relation between sets. This idea sums up the older and more modern concepts of abstraction, the first as psychological, the second as logical (or trying very hard to be!). Cf Idea 9145. |
| 9145 | We form the image of a cardinal number by a double abstraction, from the elements and from their order [Cantor] |
| Full Idea: We call 'cardinal number' the general concept which, by means of our active faculty of thought, arises when we make abstraction from an aggregate of its various elements, and of their order. From this double abstraction the number is an image in our mind. | |
| From: George Cantor (Beitrage [1915], §1), quoted by Kit Fine - Cantorian Abstraction: Recon. and Defence Intro | |
| A reaction: [compressed] This is the great Cantor, creator of set theory, endorsing the traditional abstractionism which Frege and his followers so despise. Fine offers a defence of it. The Frege view is platonist, because it refuses to connect numbers to the world. |
| 14344 | Natural kinds, such as electrons, all behave the same way because we divide them by dispositions [Mumford] |
| Full Idea: Regularities exist because we classify kinds on the basis of their dispositions, not on pre-established divisions of kinds. The dispositions are the basis for the division into kinds, which is why all electrons behave in the same way. | |
| From: Stephen Mumford (Dispositions [1998], 10.7) | |
| A reaction: This strikes me as being so obvious that it is hardly worth saying, and yet an enormous number of philosophers seem to have been led up the garden path by the notion of a 'kind', probably under the influence of Kripke, Putnam and Wiggins. |
| 19068 | Causation interests us because we want to explain change [Mumford] |
| Full Idea: Like Aristotle, the reason we are really interested in causation is because we want to be able to explain change. | |
| From: Stephen Mumford (Contemporary Efficient Causation: Aristotelian themes [2014], 8) | |
| A reaction: This pinpoints a very important and simple idea. It raises the question (among others) of whether we have just invented this thing called 'causation', because no explanation of change was visible. Hume certainly couldn't see any explanation. |
| 9430 | Singular causes, and identities, might be necessary without falling under a law [Mumford] |
| Full Idea: One might have a singularist view of causation in which a cause necessitates its effect, but they need not be subsumed under a law, ..and there are identities which are metaphysically necessary without being laws of nature. | |
| From: Stephen Mumford (Laws in Nature [2004], 04.5) |
| 9445 | We can give up the counterfactual account if we take causal language at face value [Mumford] |
| Full Idea: If we take causal language at face value and give up reducing causal concepts to non-causal, non-modal concepts, we can give up the counterfactual dependence account. | |
| From: Stephen Mumford (Laws in Nature [2004], 10.5) |
| 9443 | It is only properties which are the source of necessity in the world [Mumford] |
| Full Idea: If laws do not give the world necessity, what does? I argue the positive case for it being properties, and properties alone, that do the job (so we might call them 'modal properties'). | |
| From: Stephen Mumford (Laws in Nature [2004], 10.1) |
| 14338 | In the 'laws' view events are basic, and properties are categorical, only existing when manifested [Mumford] |
| Full Idea: In the 'laws' world view, events are the basic ontological unit and properties are parasitic upon them. Properties exist only in virtue of their instantiation in events. Properties are categorical, because they are only manifested in the present. | |
| From: Stephen Mumford (Dispositions [1998], 10.2) | |
| A reaction: Mumford rejects this view, and I am with him all the way. The first requirement is that properties be active, and not inert. See Leibniz on this. |
| 9444 | There are four candidates for the logical form of law statements [Mumford] |
| Full Idea: The contenders for the logical form of a law statement are 1) a universally quantified conditional, 2) a second-order relation between first-order universals, 3) a functional equivalence, and 4) a dispositional characteristic of a natural kind. | |
| From: Stephen Mumford (Laws in Nature [2004], 10.3) |
| 14339 | Without laws, how can a dispositionalist explain general behaviour within kinds? [Mumford] |
| Full Idea: The problem is how, without general laws, can the dispositionalist explain why generalities in behaviour are true of kinds. | |
| From: Stephen Mumford (Dispositions [1998], 10.3) | |
| A reaction: And the answer is to make kinds depend on individuals, and not vice versa, and then point to the necessary patterns that arise from conjunctions of individual dispositions, given their identity in many individuals. |
| 14341 | Dretske and Armstrong base laws on regularities between individual properties, not between events [Mumford] |
| Full Idea: The improved Dretske/Armstrong regularity view of laws dispenses with the empiricist articulation of them in terms of events, and construes them as singular statements of fact that describe relations between properties. | |
| From: Stephen Mumford (Dispositions [1998], 10.4) | |
| A reaction: They then seem to go a bit mystical, by insisting that the properties are 'universals' (even if they have to be instantiated). Universals explain nothing. |
| 9431 | Pure regularities are rare, usually only found in idealized conditions [Mumford] |
| Full Idea: Pure regularities are not nearly as common as might have been thought, and are usually only to be found in simplified or idealized conditions. | |
| From: Stephen Mumford (Laws in Nature [2004], 05.3) | |
| A reaction: [He cites Nancy Cartwright 1999 for this view] |
| 9416 | Regularities are more likely with few instances, and guaranteed with no instances! [Mumford] |
| Full Idea: It seems that the fewer the instances, the more likely it is that there be a regularity, ..and if there are no cases at all, and no S is P, that is a regularity. | |
| From: Stephen Mumford (Laws in Nature [2004], 03.3) | |
| A reaction: [He attributes the second point to Molnar] |
| 9441 | Regularity laws don't explain, because they have no governing role [Mumford] |
| Full Idea: A regularity-law does not explain its instances, because such laws play no role in determining or governing their instances. | |
| From: Stephen Mumford (Laws in Nature [2004], 09.7) | |
| A reaction: Good. It has always seemed to me entirely vacuous to explain an event simply by saying that it falls under some law. |
| 14340 | It is a regularity that whenever a person sneezes, someone (somewhere) promptly coughs [Mumford] |
| Full Idea: It is no doubt a true regularity that every time I sneeze, someone, somewhere in the world, immediately coughs. | |
| From: Stephen Mumford (Dispositions [1998], 10.4) | |
| A reaction: Not a huge problem for the regularity theory of laws, but the first challenge that it must meet. |
| 9415 | Would it count as a regularity if the only five As were also B? [Mumford] |
| Full Idea: While it might be true that for all x, if Ax then Bx, would we really want to count it as a genuine regularity in nature if only five things were A (and all five were also B)? | |
| From: Stephen Mumford (Laws in Nature [2004], 03.3) |
| 9422 | If the best system describes a nomological system, the laws are in nature, not in the description [Mumford] |
| Full Idea: If the world really does have its own nomological structure, that a systematization merely describes, why are the laws not to be equated with the nomological structure itself, rather than with the system that describes it? | |
| From: Stephen Mumford (Laws in Nature [2004], 03.4) |
| 9421 | The best systems theory says regularities derive from laws, rather than constituting them [Mumford] |
| Full Idea: The best systems theory (of Mill-Ramsey-Lewis) says that laws are not seen as regularities but, rather, as those things from which regularities - or rather, the whole world history including the regularities and everything else - can be derived. | |
| From: Stephen Mumford (Laws in Nature [2004], 03.4) | |
| A reaction: Put this way, the theory invites questions about ontology. Regularities are just patterns in physical reality, but axioms are propositions. So are they just features of human thought, or do these axioms actuallyr reside in reality. Too weak or too strong. |
| 9432 | Laws of nature are necessary relations between universal properties, rather than about particulars [Mumford] |
| Full Idea: The core of the Dretske-Tooley-Armstrong view of the late 70s is that we have a law of nature when we have a relation of natural necessitation between universals. ..The innovation was that laws are about properties, and only indirectly about particulars. | |
| From: Stephen Mumford (Laws in Nature [2004], 06.2) | |
| A reaction: It sounds as if we should then be able to know the laws of nature a priori, since that was Russell's 1912 definition of a priori knowledge. |
| 9433 | If laws can be uninstantiated, this favours the view of them as connecting universals [Mumford] |
| Full Idea: If there are laws that are instantiated in no particulars, then this would seem to favour the theory that laws connect universals rather than particulars. | |
| From: Stephen Mumford (Laws in Nature [2004], 06.4) | |
| A reaction: There is a dispute here between the Platonic view of uninstantiated universals (Tooley) and the Aristotelian instantiated view (Armstrong). Mumford and I prefer the dispositional account. |
| 14345 | The necessity of an electron being an electron is conceptual, and won't ground necessary laws [Mumford] |
| Full Idea: The logical necessity of physical laws is not required by dispositional essentialism. An electron would not be an electron if its behaviour were different from the behaviour it has in the actual world, but this necessity is purely conceptual. | |
| From: Stephen Mumford (Dispositions [1998], 10.8) | |
| A reaction: [He is particularly aiming this at Ellis and Lierse 1994] This may be missing the point. Given those electron dispositions, the electrons necessitate law-like happenings. Whether a variable entity is called an 'electron' is trivial. |
| 9434 | Laws of nature are just the possession of essential properties by natural kinds [Mumford] |
| Full Idea: If dispositional essentialism is granted, then there is a law of nature wherever there is an essential property of a natural kind; laws are just the havings of essential properties by natural kinds. | |
| From: Stephen Mumford (Laws in Nature [2004], 07.2) | |
| A reaction: [He is expounding Ellis's view] |
| 14307 | Some dispositions are so far unknown, until we learn how to manifest them [Mumford] |
| Full Idea: It seems reasonable to assume that there are some dispositions of some things of which we are not aware because we have not yet discovered the way to get these dispositions to manifest. | |
| From: Stephen Mumford (Dispositions [1998], 03.7) | |
| A reaction: This strikes me as a pretty good description of what scientists are currently doing when, for example, they build a new particle accelerator. |
| 9437 | To distinguish accidental from essential properties, we must include possible members of kinds [Mumford] |
| Full Idea: Where properties are possessed by all kind members, we must distinguish the accidental from essential ones by considering all actual and possible kind members. | |
| From: Stephen Mumford (Laws in Nature [2004], 07.5) | |
| A reaction: This is why we must treat possibilities as features of the actual world. |
| 9439 | The Central Dilemma is how to explain an internal or external view of laws which govern [Mumford] |
| Full Idea: The Central Dilemma about laws of nature is that, if they have some governing role, then they must be internal or external to the things governed, and it is hard to give a plausible account of either view. | |
| From: Stephen Mumford (Laws in Nature [2004], 09.2) | |
| A reaction: This dilemma is the basis of Mumford's total rejection of 'laws of nature'. I think I agree. |
| 9412 | You only need laws if you (erroneously) think the world is otherwise inert [Mumford] |
| Full Idea: Laws are a solution to a problem that was misconceived. Only if you think that the world would be otherwise inactive or inanimate, do you have the need to add laws to your ontology. | |
| From: Stephen Mumford (Laws in Nature [2004], 01.5) | |
| A reaction: This is a bold and extreme view - and I agree with it. I consider laws to be quite a useful concept when discussing nature, but they are not part of the ontology, and they don't do any work. They are metaphysically hopeless. |
| 9411 | There are no laws of nature in Aristotle; they became standard with Descartes and Newton [Mumford] |
| Full Idea: Laws do not appear in Aristotle's metaphysics, and it wasn't until Descartes and Newton that laws entered the intellectual mainstream. | |
| From: Stephen Mumford (Laws in Nature [2004], 01.5) | |
| A reaction: Cf. Idea 5470. |
| 10863 | Cantor proved that three dimensions have the same number of points as one dimension [Cantor, by Clegg] |
| Full Idea: Cantor proved that one-dimensional space has exactly the same number of points as does two dimensions, or our familiar three-dimensional space. | |
| From: report of George Cantor (works [1880]) by Brian Clegg - Infinity: Quest to Think the Unthinkable Ch.14 |
| 13465 | Only God is absolutely infinite [Cantor, by Hart,WD] |
| Full Idea: Cantor said that only God is absolutely infinite. | |
| From: report of George Cantor (works [1880]) by William D. Hart - The Evolution of Logic 1 | |
| A reaction: We are used to the austere 'God of the philosophers', but this gives us an even more austere 'God of the mathematicians'. |