84 ideas
| 10987 | Three traditional names of rules are 'Simplification', 'Addition' and 'Disjunctive Syllogism' [Read] |
| Full Idea: Three traditional names for rules are 'Simplification' (P from 'P and Q'), 'Addition' ('P or Q' from P), and 'Disjunctive Syllogism' (Q from 'P or Q' and 'not-P'). | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) |
| 11004 | Necessity is provability in S4, and true in all worlds in S5 [Read] |
| Full Idea: In S4 necessity is said to be informal 'provability', and in S5 it is said to be 'true in every possible world'. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.4) | |
| A reaction: It seems that the S4 version is proof-theoretic, and the S5 version is semantic. |
| 11018 | There are fuzzy predicates (and sets), and fuzzy quantifiers and modifiers [Read] |
| Full Idea: In fuzzy logic, besides fuzzy predicates, which define fuzzy sets, there are also fuzzy quantifiers (such as 'most' and 'few') and fuzzy modifiers (such as 'usually'). | |
| From: Stephen Read (Thinking About Logic [1995], Ch.7) |
| 11011 | Same say there are positive, negative and neuter free logics [Read] |
| Full Idea: It is normal to classify free logics into three sorts; positive free logics (some propositions with empty terms are true), negative free logics (they are false), and neuter free logics (they lack truth-value), though I find this unhelpful and superficial. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.5) |
| 11020 | Realisms like the full Comprehension Principle, that all good concepts determine sets [Read] |
| Full Idea: Hard-headed realism tends to embrace the full Comprehension Principle, that every well-defined concept determines a set. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.8) | |
| A reaction: This sort of thing gets you into trouble with Russell's paradox (though that is presumably meant to be excluded somehow by 'well-defined'). There are lots of diluted Comprehension Principles. |
| 10986 | Not all validity is captured in first-order logic [Read] |
| Full Idea: We must recognise that first-order classical logic is inadequate to describe all valid consequences, that is, all cases in which it is impossible for the premisses to be true and the conclusion false. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) | |
| A reaction: This is despite the fact that first-order logic is 'complete', in the sense that its own truths are all provable. |
| 10972 | The non-emptiness of the domain is characteristic of classical logic [Read] |
| Full Idea: The non-emptiness of the domain is characteristic of classical logic. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) |
| 11024 | Semantics must precede proof in higher-order logics, since they are incomplete [Read] |
| Full Idea: For the realist, study of semantic structures comes before study of proofs. In higher-order logic is has to, for the logics are incomplete. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.9) | |
| A reaction: This seems to be an important general observation about any incomplete system, such as Peano arithmetic. You may dream the old rationalist dream of starting from the beginning and proving everything, but you can't. Start with truth and meaning. |
| 10985 | We should exclude second-order logic, precisely because it captures arithmetic [Read] |
| Full Idea: Those who believe mathematics goes beyond logic use that fact to argue that classical logic is right to exclude second-order logic. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) |
| 10970 | A theory of logical consequence is a conceptual analysis, and a set of validity techniques [Read] |
| Full Idea: A theory of logical consequence, while requiring a conceptual analysis of consequence, also searches for a set of techniques to determine the validity of particular arguments. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) |
| 10984 | Logical consequence isn't just a matter of form; it depends on connections like round-square [Read] |
| Full Idea: If classical logic insists that logical consequence is just a matter of the form, we fail to include as valid consequences those inferences whose correctness depends on the connections between non-logical terms (such as 'round' and 'square'). | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) | |
| A reaction: He suggests that an inference such as 'round, so not square' should be labelled as 'materially valid'. |
| 10973 | A theory is logically closed, which means infinite premisses [Read] |
| Full Idea: A 'theory' is any logically closed set of propositions, ..and since any proposition has infinitely many consequences, including all the logical truths, so that theories have infinitely many premisses. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) | |
| A reaction: Read is introducing this as the essential preliminary to an account of the Compactness Theorem, which relates these infinite premisses to the finite. |
| 11007 | Quantifiers are second-order predicates [Read] |
| Full Idea: Quantifiers are second-order predicates. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.5) | |
| A reaction: [He calls this 'Frege's insight'] They seem to be second-order in Tarski's sense, that they are part of a metalanguage about the sentence, rather than being a part of the sentence. |
| 10978 | In second-order logic the higher-order variables range over all the properties of the objects [Read] |
| Full Idea: The defining factor of second-order logic is that, while the domain of its individual variables may be arbitrary, the range of the first-order variables is all the properties of the objects in its domain (or, thinking extensionally, of the sets objects). | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) | |
| A reaction: The key point is that the domain is 'all' of the properties. How many properties does an object have. You need to decide whether you believe in sparse or abundant properties (I vote for very sparse indeed). |
| 10971 | A logical truth is the conclusion of a valid inference with no premisses [Read] |
| Full Idea: Logical truth is a degenerate, or extreme, case of consequence. A logical truth is the conclusion of a valid inference with no premisses, or a proposition in the premisses of an argument which is unnecessary or may be suppressed. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) |
| 10988 | Any first-order theory of sets is inadequate [Read] |
| Full Idea: Any first-order theory of sets is inadequate because of the Löwenheim-Skolem-Tarski property, and the consequent Skolem paradox. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) | |
| A reaction: The limitation is in giving an account of infinities. |
| 10974 | Compactness is when any consequence of infinite propositions is the consequence of a finite subset [Read] |
| Full Idea: Classical logical consequence is compact, which means that any consequence of an infinite set of propositions (such as a theory) is a consequence of some finite subset of them. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) |
| 10975 | Compactness does not deny that an inference can have infinitely many premisses [Read] |
| Full Idea: Compactness does not deny that an inference can have infinitely many premisses. It can; but classically, it is valid if and only if the conclusion follows from a finite subset of them. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) |
| 10977 | Compactness blocks the proof of 'for every n, A(n)' (as the proof would be infinite) [Read] |
| Full Idea: Compact consequence undergenerates - there are intuitively valid consequences which it marks as invalid, such as the ω-rule, that if A holds of the natural numbers, then 'for every n, A(n)', but the proof of that would be infinite, for each number. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) |
| 10976 | Compactness makes consequence manageable, but restricts expressive power [Read] |
| Full Idea: Compactness is a virtue - it makes the consequence relation more manageable; but it is also a limitation - it limits the expressive power of the logic. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) | |
| A reaction: The major limitation is that wholly infinite proofs are not permitted, as in Idea 10977. |
| 11014 | Self-reference paradoxes seem to arise only when falsity is involved [Read] |
| Full Idea: It cannot be self-reference alone that is at fault. Rather, what seems to cause the problems in the paradoxes is the combination of self-reference with falsity. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.6) |
| 11025 | Infinite cuts and successors seems to suggest an actual infinity there waiting for us [Read] |
| Full Idea: Every potential infinity seems to suggest an actual infinity - e.g. generating successors suggests they are really all there already; cutting the line suggests that the point where the cut is made is already in place. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.8) | |
| A reaction: Finding a new gambit in chess suggests it was there waiting for us, but we obviously invented chess. Daft. |
| 10979 | Although second-order arithmetic is incomplete, it can fully model normal arithmetic [Read] |
| Full Idea: Second-order arithmetic is categorical - indeed, there is a single formula of second-order logic whose only model is the standard model ω, consisting of just the natural numbers, with all of arithmetic following. It is nevertheless incomplete. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) | |
| A reaction: This is the main reason why second-order logic has a big fan club, despite the logic being incomplete (as well as the arithmetic). |
| 10980 | Second-order arithmetic covers all properties, ensuring categoricity [Read] |
| Full Idea: Second-order arithmetic can rule out the non-standard models (with non-standard numbers). Its induction axiom crucially refers to 'any' property, which gives the needed categoricity for the models. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) |
| 10997 | Von Neumann numbers are helpful, but don't correctly describe numbers [Read] |
| Full Idea: The Von Neumann numbers have a structural isomorphism to the natural numbers - each number is the set of all its predecessors, so 2 is the set of 0 and 1. This helps proofs, but is unacceptable. 2 is not a set with two members, or a member of 3. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.4) |
| 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. |
| 11016 | Would a language without vagueness be usable at all? [Read] |
| Full Idea: We must ask whether a language without vagueness would be usable at all. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.7) | |
| A reaction: Popper makes a similar remark somewhere, with which I heartily agreed. This is the idea of 'spreading the word' over the world, which seems the right way of understanding it. |
| 11019 | Supervaluations say there is a cut-off somewhere, but at no particular place [Read] |
| Full Idea: The supervaluation approach to vagueness is to construe vague predicates not as ones with fuzzy borderlines and no cut-off, but as having a cut-off somewhere, but in no particular place. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.7) | |
| A reaction: Presumably you narrow down the gap by supervaluation, then split the difference to get a definite value. |
| 11012 | A 'supervaluation' gives a proposition consistent truth-value for classical assignments [Read] |
| Full Idea: A 'supervaluation' says a proposition is true if it is true in all classical extensions of the original partial valuation. Thus 'A or not-A' has no valuation for an empty name, but if 'extended' to make A true or not-true, not-A always has opposite value. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.5) |
| 11013 | Identities and the Indiscernibility of Identicals don't work with supervaluations [Read] |
| Full Idea: In supervaluations, the Law of Identity has no value for empty names, and remains so if extended. The Indiscernibility of Identicals also fails if extending it for non-denoting terms, where Fa comes out true and Fb false. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.5) |
| 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). |
| 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. |
| 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. |
| 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. |
| 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. |
| 10995 | A haecceity is a set of individual properties, essential to each thing [Read] |
| Full Idea: The haecceitist (a neologism coined by Duns Scotus, pronounced 'hex-ee-it-ist', meaning literally 'thisness') believes that each thing has an individual essence, a set of properties which are essential to it. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.4) | |
| A reaction: This seems to be a difference of opinion over whether a haecceity is a set of essential properties, or a bare particular. The key point is that it is unique to each entity. |
| 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. |
| 11001 | Equating necessity with truth in every possible world is the S5 conception of necessity [Read] |
| Full Idea: The equation of 'necessity' with 'true in every possible world' is known as the S5 conception, corresponding to the strongest of C.I.Lewis's five modal systems. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.4) | |
| A reaction: Are the worlds naturally, or metaphysically, or logically possible? |
| 10992 | The point of conditionals is to show that one will accept modus ponens [Read] |
| Full Idea: The point of conditionals is to show that one will accept modus ponens. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.3) | |
| A reaction: [He attributes this idea to Frank Jackson] This makes the point, against Grice, that the implication of conditionals is not conversational but a matter of logical convention. See Idea 21396 for a very different view. |
| 10989 | The standard view of conditionals is that they are truth-functional [Read] |
| Full Idea: The standard view of conditionals is that they are truth-functional, that is, that their truth-values are determined by the truth-values of their constituents. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.3) |
| 11017 | Some people even claim that conditionals do not express propositions [Read] |
| Full Idea: Some people even claim that conditionals do not express propositions. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.7) | |
| A reaction: See Idea 14283, where this appears to have been 'proved' by Lewis, and is not just a view held by some people. |
| 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. |
| 10983 | Knowledge of possible worlds is not causal, but is an ontology entailed by semantics [Read] |
| Full Idea: The modal Platonist denies that knowledge always depends on a causal relation. The reality of possible worlds is an ontological requirement, to secure the truth-values of modal propositions. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) | |
| A reaction: [Reply to Idea 10982] This seems to be a case of deriving your metaphyics from your semantics, of which David Lewis seems to be guilty, and which strikes me as misguided. |
| 10982 | How can modal Platonists know the truth of a modal proposition? [Read] |
| Full Idea: If modal Platonism was true, how could we ever know the truth of a modal proposition? | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) | |
| A reaction: I take this to be very important. Our knowledge of modal truths must depend on our knowledge of the actual world. The best answer seems to involve reference to the 'powers' of the actual world. A reply is in Idea 10983. |
| 10996 | Actualism is reductionist (to parts of actuality), or moderate realist (accepting real abstractions) [Read] |
| Full Idea: There are two main forms of actualism: reductionism, which seeks to construct possible worlds out of some more mundane material; and moderate realism, in which the actual concrete world is contrasted with abstract, but none the less real, possible worlds. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.4) | |
| A reaction: I am a reductionist, as I do not take abstractions to be 'real' (precisely because they have been 'abstracted' from the things that are real). I think I will call myself a 'scientific modalist' - we build worlds from possibilities, discovered by science. |
| 10981 | A possible world is a determination of the truth-values of all propositions of a domain [Read] |
| Full Idea: A possible world is a complete determination of the truth-values of all propositions over a certain domain. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.2) | |
| A reaction: Even if the domain is very small? Even if the world fitted the logic nicely, but was naturally impossible? |
| 11000 | If worlds are concrete, objects can't be present in more than one, and can only have counterparts [Read] |
| Full Idea: If each possible world constitutes a concrete reality, then no object can be present in more than one world - objects may have 'counterparts', but cannot be identical with them. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.4) | |
| A reaction: This explains clearly why in Lewis's modal realist scheme he needs counterparts instead of rigid designation. Sounds like a slippery slope. If you say 'Humphrey might have won the election', who are you talking about? |
| 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. |
| 10998 | The mind abstracts ways things might be, which are nonetheless real [Read] |
| Full Idea: Ways things might be are real, but only when abstracted from the actual way things are. They are brought out and distinguished by the mind, by abstraction, but are not dependent on mind for their existence. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.4) | |
| A reaction: To me this just flatly contradicts itself. The idea that the mind can 'bring something out' by its operations, with the result being then accepted as part of reality is nonsense on stilts. What is real is the powers that make the possibilities. |
| 11005 | Negative existentials with compositionality make the whole sentence meaningless [Read] |
| Full Idea: A problem with compositionality is negative existential propositions. If some of the terms of the proposition are empty, and don't refer, then compositionality implies that the whole will lack meaning too. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.5) | |
| A reaction: I don't agree. I don't see why compositionality implies holism about sentence-meaning. If I say 'that circular square is a psychopath', you understand the predication, despite being puzzled by the singular term. |
| 10966 | A proposition objectifies what a sentence says, as indicative, with secure references [Read] |
| Full Idea: A proposition makes an object out of what is said or expressed by the utterance of a certain sort of sentence, namely, one in the indicative mood which makes sense and doesn't fail in its references. It can then be an object of thought and belief. | |
| From: Stephen Read (Thinking About Logic [1995], Ch.1) | |
| A reaction: Nice, but two objections: I take it to be crucial to propositions that they eliminate ambiguities, and I take it that animals are capable of forming propositions. Read seems to regard them as fictions, but I take them to be brain events. |
| 6017 | Nomos is king [Pindar] |
| Full Idea: Nomos is king. | |
| From: Pindar (poems [c.478 BCE], S 169), quoted by Thomas Nagel - The Philosophical Culture | |
| A reaction: This seems to be the earliest recorded shot in the nomos-physis wars (the debate among sophists about moral relativism). It sounds as if it carries the full relativist burden - that all that matters is what has been locally decreed. |
| 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. |
| 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. |
| 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. |
| 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. |
| 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. |
| 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. |