53 ideas
| 13520 | A 'tautology' must include connectives [Wolf,RS] |
| Full Idea: 'For every number x, x = x' is not a tautology, because it includes no connectives. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], 1.2) |
| 13524 | Deduction Theorem: T∪{P}|-Q, then T|-(P→Q), which justifies Conditional Proof [Wolf,RS] |
| Full Idea: Deduction Theorem: If T ∪ {P} |- Q, then T |- (P → Q). This is the formal justification of the method of conditional proof (CPP). Its converse holds, and is essentially modus ponens. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], 1.3) |
| 13522 | Universal Generalization: If we prove P(x) with no special assumptions, we can conclude ∀xP(x) [Wolf,RS] |
| Full Idea: Universal Generalization: If we can prove P(x), only assuming what sort of object x is, we may conclude ∀xP(x) for the same x. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], 1.3) | |
| A reaction: This principle needs watching closely. If you pick one person in London, with no presuppositions, and it happens to be a woman, can you conclude that all the people in London are women? Fine in logic and mathematics, suspect in life. |
| 13521 | Universal Specification: ∀xP(x) implies P(t). True for all? Then true for an instance [Wolf,RS] |
| Full Idea: Universal Specification: from ∀xP(x) we may conclude P(t), where t is an appropriate term. If something is true for all members of a domain, then it is true for some particular one that we specify. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], 1.3) |
| 13523 | Existential Generalization (or 'proof by example'): if we can say P(t), then we can say something is P [Wolf,RS] |
| Full Idea: Existential Generalization (or 'proof by example'): From P(t), where t is an appropriate term, we may conclude ∃xP(x). | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], 1.3) | |
| A reaction: It is amazing how often this vacuous-sounding principles finds itself being employed in discussions of ontology, but I don't quite understand why. |
| 10455 | Free logic at least allows empty names, but struggles to express non-existence [Bach] |
| Full Idea: Unlike standard first-order logic, free logic can allow empty names, but still has to deny existence by either representing it as a predicate, or invoke some dubious distinction such as between existence and being. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.2 L1) |
| 13529 | Empty Set: ∃x∀y ¬(y∈x). The unique empty set exists [Wolf,RS] |
| Full Idea: Empty Set Axiom: ∃x ∀y ¬ (y ∈ x). There is a set x which has no members (no y's). The empty set exists. There is a set with no members, and by extensionality this set is unique. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], 2.3) | |
| A reaction: A bit bewildering for novices. It says there is a box with nothing in it, or a pair of curly brackets with nothing between them. It seems to be the key idea in set theory, because it asserts the idea of a set over and above any possible members. |
| 13526 | Comprehension Axiom: if a collection is clearly specified, it is a set [Wolf,RS] |
| Full Idea: The comprehension axiom says that any collection of objects that can be clearly specified can be considered to be a set. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], 2.2) | |
| A reaction: This is virtually tautological, since I presume that 'clearly specified' means pinning down exact which items are the members, which is what a set is (by extensionality). The naïve version is, of course, not so hot. |
| 13534 | In first-order logic syntactic and semantic consequence (|- and |=) nicely coincide [Wolf,RS] |
| Full Idea: One of the most appealing features of first-order logic is that the two 'turnstiles' (the syntactic single |-, and the semantic double |=), which are the two reasonable notions of logical consequence, actually coincide. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], 5.3) | |
| A reaction: In the excitement about the possibility of second-order logic, plural quantification etc., it seems easy to forget the virtues of the basic system that is the target of the rebellion. The issue is how much can be 'expressed' in first-order logic. |
| 13535 | First-order logic is weakly complete (valid sentences are provable); we can't prove every sentence or its negation [Wolf,RS] |
| Full Idea: The 'completeness' of first order-logic does not mean that every sentence or its negation is provable in first-order logic. We have instead the weaker result that every valid sentence is provable. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], 5.3) | |
| A reaction: Peter Smith calls the stronger version 'negation completeness'. |
| 10454 | In first-order we can't just assert existence, and it is very hard to deny something's existence [Bach] |
| Full Idea: In standard logic we can't straightforwardly say that n exists. We have to resort to using a formula like '∃x(x=n)', but we can't deny n's existence by negating that formula, because standard first-order logic disallows empty names. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.2 L1) |
| 10453 | In logic constants play the role of proper names [Bach] |
| Full Idea: In standard first-order logic the role of proper names is played by individual constants. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.2 L1) |
| 10452 | Proper names can be non-referential - even predicate as well as attributive uses [Bach] |
| Full Idea: Like it or not, proper names have non-referential uses, including not only attributive but even predicate uses. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.2 L1) | |
| A reaction: 'He's a right little Hitler'. 'You're doing a George Bush again'. 'Try to live up to the name of Churchill'. |
| 10456 | Millian names struggle with existence, empty names, identities and attitude ascription [Bach] |
| Full Idea: The familiar problems with the Millian view of names are the problem of positive and negative existential statements, empty names, identity sentences, and propositional attitude ascription. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.2 L1) | |
| A reaction: I take this combination of problems to make an overwhelming case against the daft idea that the semantics of a name amounts to the actual object it picks out. It is a category mistake to attempt to insert a person into a sentence. |
| 10440 | An object can be described without being referred to [Bach] |
| Full Idea: An object can be described without being referred to. | |
| From: Kent Bach (What Does It Take to Refer? [2006], Intro) | |
| A reaction: I'm not clear how this is possible for a well-known object, though it is clearly possible for a speculative object, such as a gadget I would like to buy. In the former case reference seems to occur even if the speaker is trying to avoid it. |
| 10444 | Definite descriptions can be used to refer, but are not semantically referential [Bach] |
| Full Idea: If Russell is, as I believe, basically right, then definite descriptions are the paradigm of singular terms that can be used to refer but are not linguistically (semantically) referential. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.1 s5) | |
| A reaction: I'm not sure that we can decide what is 'semantically referential'. Most of the things we refer to don't have names. We don't then 'use' definite descriptions (I'm thinking) - they actually DO the job. If we use them, we can 'use' names too? |
| 13519 | Model theory uses sets to show that mathematical deduction fits mathematical truth [Wolf,RS] |
| Full Idea: Model theory uses set theory to show that the theorem-proving power of the usual methods of deduction in mathematics corresponds perfectly to what must be true in actual mathematical structures. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], Pref) | |
| A reaction: That more or less says that model theory demonstrates the 'soundness' of mathematics (though normal arithmetic is famously not 'complete'). Of course, he says they 'correspond' to the truths, rather than entailing them. |
| 13533 | First-order model theory rests on completeness, compactness, and the Löwenheim-Skolem-Tarski theorem [Wolf,RS] |
| Full Idea: The three foundations of first-order model theory are the Completeness theorem, the Compactness theorem, and the Löwenheim-Skolem-Tarski theorem. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], 5.3) | |
| A reaction: On p.180 he notes that Compactness and LST make no mention of |- and are purely semantic, where Completeness shows the equivalence of |- and |=. All three fail for second-order logic (p.223). |
| 13532 | Model theory 'structures' have a 'universe', some 'relations', some 'functions', and some 'constants' [Wolf,RS] |
| Full Idea: A 'structure' in model theory has a non-empty set, the 'universe', as domain of variables, a subset for each 'relation', some 'functions', and 'constants'. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], 5.2) |
| 13531 | Model theory reveals the structures of mathematics [Wolf,RS] |
| Full Idea: Model theory helps one to understand what it takes to specify a mathematical structure uniquely. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], 5.1) | |
| A reaction: Thus it is the development of model theory which has led to the 'structuralist' view of mathematics. |
| 13537 | An 'isomorphism' is a bijection that preserves all structural components [Wolf,RS] |
| Full Idea: An 'isomorphism' is a bijection between two sets that preserves all structural components. The interpretations of each constant symbol are mapped across, and functions map the relation and function symbols. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], 5.4) |
| 13539 | The LST Theorem is a serious limitation of first-order logic [Wolf,RS] |
| Full Idea: The Löwenheim-Skolem-Tarski theorem demonstrates a serious limitation of first-order logic, and is one of primary reasons for considering stronger logics. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], 5.7) |
| 13538 | If a theory is complete, only a more powerful language can strengthen it [Wolf,RS] |
| Full Idea: It is valuable to know that a theory is complete, because then we know it cannot be strengthened without passing to a more powerful language. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], 5.5) |
| 13525 | Most deductive logic (unlike ordinary reasoning) is 'monotonic' - we don't retract after new givens [Wolf,RS] |
| Full Idea: Deductive logic, including first-order logic and other types of logic used in mathematics, is 'monotonic'. This means that we never retract a theorem on the basis of new givens. If T|-φ and T⊆SW, then S|-φ. Ordinary reasoning is nonmonotonic. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], 1.7) | |
| A reaction: The classic example of nonmonotonic reasoning is the induction that 'all birds can fly', which is retracted when the bird turns out to be a penguin. He says nonmonotonic logic is a rich field in computer science. |
| 13530 | An ordinal is an equivalence class of well-orderings, or a transitive set whose members are transitive [Wolf,RS] |
| Full Idea: Less theoretically, an ordinal is an equivalence class of well-orderings. Formally, we say a set is 'transitive' if every member of it is a subset of it, and an ordinal is a transitive set, all of whose members are transitive. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], 2.4) | |
| A reaction: He glosses 'transitive' as 'every member of a member of it is a member of it'. So it's membership all the way down. This is the von Neumann rather than the Zermelo approach (which is based on singletons). |
| 13518 | Modern mathematics has unified all of its objects within set theory [Wolf,RS] |
| Full Idea: One of the great achievements of modern mathematics has been the unification of its many types of objects. It began with showing geometric objects numerically or algebraically, and culminated with set theory representing all the normal objects. | |
| From: Robert S. Wolf (A Tour through Mathematical Logic [2005], Pref) | |
| A reaction: His use of the word 'object' begs all sorts of questions, if you are arriving from the street, where an object is something which can cause a bruise - but get used to it, because the word 'object' has been borrowed for new uses. |
| 8439 | Maybe each event has only one possible causal history [Bennett] |
| Full Idea: Perhaps it is impossible that an event should have had a causal history different from the one that it actually had. | |
| From: Jonathan Bennett (Event Causation: counterfactual analysis [1987], p.220) | |
| A reaction: [He cites van Inwagen for this] The idea is analagous to baptismal accounts of reference. Individuate an event by its history. It might depend (as Davidson implies) on how you describe the event. |
| 8440 | Maybe an event's time of occurrence is essential to it [Bennett] |
| Full Idea: It has been argued that an event's time of occurrence is essential to it. | |
| From: Jonathan Bennett (Event Causation: counterfactual analysis [1987], p.221) | |
| A reaction: [He cites Lawrence Lombard] This sound initially implausible, particularly if a rival event happened, say, .1 of a second later than the actual event. It might depend on one's view about determinism. Interesting. |
| 8978 | Events are made of other things, and are not fundamental to ontology [Bennett] |
| Full Idea: Events are not basic items in the universe; they should not be included in any fundamental ontology...all the truths about them are entailed by and explained and made true by truths that do not involve the event concept. | |
| From: Jonathan Bennett (Events and Their Names [1988], p.12), quoted by Peter Simons - Events 3.1 | |
| A reaction: Given the variable time spans of events, their ability to coincide, their ability to contain no motion, their blatantly conventional component, and their recalcitrance to individuation, I say Bennett is right. |
| 12900 | How could 'S knows he has hands' not have a fixed content? [Bach] |
| Full Idea: How can it be that a sentence like 'George knows that he has hands', even with time and references fixed, does not have a fixed propositional content? | |
| From: Kent Bach (The Emperor's New 'Knows' [2005], I) | |
| A reaction: The appeal is to G.E. Moore's common sense view of immediate knowledge (Idea 6349). The reply is simply that the word 'knows' shifts its meaning, having high standards in sceptical philosophy classes, and low standards on the street. |
| 12901 | If contextualism is right, knowledge sentences are baffling out of their context [Bach] |
| Full Idea: Contextualism seems to predict that if you encounter a knowledge attribution out of context you won't be in a position to grasp which proposition the sentence expresses. | |
| From: Kent Bach (The Emperor's New 'Knows' [2005], I) | |
| A reaction: It is only the word 'knows' which is at issue in the sentence. If someone is said to 'know' about the world of the fairies, we might well be puzzled as to what proposition was being expressed. Is the word 'flat' baffling out of context? |
| 12902 | Sceptics aren't changing the meaning of 'know', but claiming knowing is tougher than we think [Bach] |
| Full Idea: When a sceptic brings up far-fetched possibilities and argues that we can't rule them out, he is not raising the standard for the word 'know'. He is showing it is tougher than we realise for a belief to qualify as normal knowledge at all. | |
| From: Kent Bach (The Emperor's New 'Knows' [2005], III) | |
| A reaction: [Bach cites Richard Feldman for this idea] I think that what happens in the contextual account is that 'true', 'belief' and 'know' retain their standard meaning, and it is 'justified' which shifts. 'I am fully justified' can have VERY different meanings! |
| 10446 | Fictional reference is different inside and outside the fiction [Bach] |
| Full Idea: We must distinguish 'reference' in a fiction from reference outside the fiction to fictional entities. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.1) | |
| A reaction: This may be more semantically than ontologically significant. It is perhaps best explicated by Coleridge's distinction over whether or not I am 'suspending my disbelief' when I am discussing a character. |
| 10447 | We can refer to fictional entities if they are abstract objects [Bach] |
| Full Idea: If fictional entities, such as characters in a play, are real, albeit abstract entities, then we can genuinely refer to them. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.1) | |
| A reaction: [He cites Nathan Salmon 1998] Personally I would prefer to say that abstract entities are fictions. Fictional characters have uncertain identity conditions. Do they all have a pancreas, if this is never mentioned? |
| 10443 | You 'allude to', not 'refer to', an individual if you keep their identity vague [Bach] |
| Full Idea: If you say 'a special person is coming to visit', you are not referring to but merely 'alluding to' that individual. This does not count as referring because you are not expressing a singular proposition about it. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.1 s2) | |
| A reaction: If you add 'I hope he doesn't wear his red suit, but I hope he plays his tuba', you seem to be expressing singular propositions about the person. Bach seems to want a very strict notion of reference, as really attaching listeners to individuals. |
| 10439 | What refers: indefinite or definite or demonstrative descriptions, names, indexicals, demonstratives? [Bach] |
| Full Idea: Philosophers agree that some expressions refer, but disagree over which ones. Few include indefinite descriptions, but some include definite descriptions, or only demonstrative descriptions. Some like proper names, some only indexicals and demonstratives. | |
| From: Kent Bach (What Does It Take to Refer? [2006], Intro) | |
| A reaction: My initial prejudice is rather Strawsonian - that people refer, not language, and it can be done in all sorts of ways. But Bach argues well that only language intrinsically does it. Even pointing fails without linguistic support. |
| 10441 | If we can refer to things which change, we can't be obliged to single out their properties [Bach] |
| Full Idea: We can refer to things which change over time, which suggests that in thinking of and in referring to an individual we are not constrained to represent it as that which has certain properties. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.1) | |
| A reaction: This seems a good argument against the descriptive theory of reference which is not (I think) in Kripke. Problems like vagueness and the Ship of Theseus rear their heads. |
| 10442 | We can think of an individual without have a uniquely characterizing description [Bach] |
| Full Idea: Being able to think of an individual does not require being able to identify that individual by means of a uniquely characterizing description. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.1 s1) | |
| A reaction: There is a bit of an equivocation over 'recognise' here. His example is 'the first child born in the 4th century'. We can't visually recognise such people, but the description does fix them, and a records office might give us 'recognition'. |
| 10445 | It can't be real reference if it could refer to some other thing that satisfies the description [Bach] |
| Full Idea: If one is referring to whatever happens to satisfy a description, and one would be referring to something else were it to have satisfied the description instead, this is known as 'weak' reference,...but surely this is not reference at all. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.1 s7) | |
| A reaction: Bach wants a precise notion of reference, as success in getting the audience to focus on the correct object. He talks of this case as 'singling out' some unfixed thing, and he also has 'alluding to' an unstated thing. Plausible view. |
| 10457 | Since most expressions can be used non-referentially, none of them are inherently referential [Bach] |
| Full Idea: An embarrassingly simple argument is that most expressions can be used literally but not referentially, no variation in meaning explains this fact, so its meaning is compatible with being non-referential, so no expression is inherently referential. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.2 L2) | |
| A reaction: I think I have decided that no expression is 'inherently referential', and that it is all pragmatics. |
| 10463 | Just alluding to or describing an object is not the same as referring to it [Bach] |
| Full Idea: Much of what speakers do that passes for referring is merely alluding or describing. ...It is one thing for a speaker to express a thought about a certain object using an expression, and quite another for the expression to stand for that object. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.3) | |
| A reaction: Bach builds up a persuasive case for this view. If the question, though, is 'what are you talking about?', then saying what is being alluded to or singled out or described seems fine. Bach is being rather stipulative. |
| 10459 | Context does not create reference; it is just something speakers can exploit [Bach] |
| Full Idea: Context does not determine or constitute reference; rather, it is something for the speaker to exploit to enable the listener to determine the intended reference. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.2 L3) | |
| A reaction: Bach thinks linguistic reference is a matter of speaker's intentions, and I think he is right. And this idea is right too. The domain of quantification constantly shifts in a conversation, and good speakers and listeners are sensitive to this. |
| 10460 | 'That duck' may not refer to the most obvious one in the group [Bach] |
| Full Idea: If one ducks starts quacking furiously, and you say 'that duck is excited', it isn't context that makes me take it that you are referring to the quacking duck. You could be referring to a quiet duck you recognise by its distinctive colour. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.2 L3) | |
| A reaction: A persuasive example to make his point against the significance of context in conversational reference. Speaker's intended reference must always trump any apparent reference suggested by context. |
| 10461 | What a pronoun like 'he' refers back to is usually a matter of speaker's intentions [Bach] |
| Full Idea: To illustrate speakers' intentions, consider the anaphoric reference using pronouns in these: "A cop arrested a robber; he was wearing a badge", and "A cop arrested a robber; he was wearing a mask". The natural supposition is not the inevitable one. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.2 L4) | |
| A reaction: I am a convert to speakers' intentions as the source of all reference, and this example seems to illustrate it very well. 'He said..' 'Who said?' |
| 10462 | Information comes from knowing who is speaking, not just from interpretation of the utterance [Bach] |
| Full Idea: It is a fallacy that all the information in an utterance must come from its interpretation, which ignores the essentially pragmatic fact that the speaker is making the utterance. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.2 L4) | |
| A reaction: [He cites Barwise and Perry 1983:34] This is blatantly obvious in indexical remarks like 'I am tired', where the words don't tell you who is tired. But also 'the car has broken down, dear'. |
| 10458 | People slide from contextual variability all the way to contextual determination [Bach] |
| Full Idea: People slide from contextual variability to context relativity to context sensitivity to context dependence to contextual determination. | |
| From: Kent Bach (What Does It Take to Refer? [2006], 22.2 L3) | |
| A reaction: This is reminiscent of the epistemological slide from cultural or individual relativity of some observed things, to a huge metaphysical denial of truth. Bach's warning applies to me, as I have been drifting down his slope lately. Nice. |
| 8441 | Delaying a fire doesn't cause it, but hastening it might [Bennett] |
| Full Idea: Although you cannot cause a fire by delaying something's burning, you can cause a fire by hastening something's burning. | |
| From: Jonathan Bennett (Event Causation: counterfactual analysis [1987], p.223) | |
| A reaction: A very nice observation which brings out all sorts of problems about identifying causes. Bennett is criticising the counterfactual account. It is part of the problem of pre-emption, where causes are queueing up to produce a given effect. |
| 8436 | Either cause and effect are subsumed under a conditional because of properties, or it is counterfactual [Bennett] |
| Full Idea: We must choose between subsumption and counterfactual analyses of causal statements. The former means that cause and effect have some properties that enables them to be subsumed under a conditional. The latter is just 'if no-c then no-e'. | |
| From: Jonathan Bennett (Event Causation: counterfactual analysis [1987], p.217) | |
| A reaction: I have an immediate preference for the former account, which seems to potentially connect it with physics and features of the world which make one thing lead to another. The counterfactual account seems very thin, and is more like mere semantics. |
| 8435 | Causes are between events ('the explosion') or between facts/states of affairs ('a bomb dropped') [Bennett] |
| Full Idea: Theories of causation are split between event and fact/state of affairs theories. The first have the form 'the explosion caused the fire' (perfect nominals) and the second have the form 'the fire started because a bomb dropped' (sentential clauses). | |
| From: Jonathan Bennett (Event Causation: counterfactual analysis [1987]) | |
| A reaction: Surely events must have priority? The form which uses facts is drifting off into explanation, and is much more likely to involve subjective human elements and interpretations. Events are closer to the physics, and the mechanics of what happens. |
| 10364 | Facts are about the world, not in it, so they can't cause anything [Bennett] |
| Full Idea: Facts are not the sort of item that can cause anything. A fact is a true proposition (they say); it is not something in the world but is rather something about the world. | |
| From: Jonathan Bennett (Events and Their Names [1988], p.22), quoted by Jonathan Schaffer - The Metaphysics of Causation 1.1 | |
| A reaction: Compare 10361. Good argument, but maybe 'fact' is ambiguous. See Idea 10365. Events are said to be more concrete, and so can do the job, but their individuation also seems to depend on a description (as Davidson has pointed out). |
| 8437 | The full counterfactual story asserts a series of events, because counterfactuals are not transitive [Bennett] |
| Full Idea: The refinement of a simple counterfactual analysis is to say that cause and effect depend on a series of events. This must be asserted because counterfactual conditionals are well known not to be transitive. | |
| From: Jonathan Bennett (Event Causation: counterfactual analysis [1987]) | |
| A reaction: This fills out the theory, but offers another target for critics. If the glue that binds the series is not in the counterfactuals, is it just in the mind of the speaker? How do you decide what's in the series? Cf. deciding offside in football (soccer!). |
| 8438 | A counterfactual about an event implies something about the event's essence [Bennett] |
| Full Idea: Any counterfactual about a particular event implies or presupposes something about the event's essence. | |
| From: Jonathan Bennett (Event Causation: counterfactual analysis [1987], p.219) | |
| A reaction: This is where the counterfactual theory suddenly becomes more interesting, instead of just being a rather bare account of the logical structure of causation. (Bennett offers some discussion of possible essential implications). |
| 8592 | Empty space is measurable in ways in which empty time necessarily is not [Bennett, by Shoemaker] |
| Full Idea: Because of the multidimensionality of space and unidimensionality of time, empty space is measurable in ways in which empty time necessarily is not. | |
| From: report of Jonathan Bennett (Kant's Analytic [1966], p.175) by Sydney Shoemaker - Time Without Change p.49 n4 | |
| A reaction: An interesting observation, which could have been used by Samuel Clarke in his attempts to prove absolute space to Leibniz. The point does not prove absolute space, of course, but it seems to make a difference. |