31 ideas
| 15647 | Truth definitions don't produce a good theory, because they go beyond your current language [Halbach] |
| Full Idea: It is far from clear that a definition of truth can lead to a philosophically satisfactory theory of truth. Tarski's theorem on the undefinability of the truth predicate needs resources beyond those of the language for which it is being defined. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1) | |
| A reaction: The idea is that you need a 'metalanguage' for the definition. If I say 'p' is a true sentence in language 'L', I am not making that observation from within language L. The dream is a theory confined to the object language. |
| 15649 | In semantic theories of truth, the predicate is in an object-language, and the definition in a metalanguage [Halbach] |
| Full Idea: In semantic theories of truth (Tarski or Kripke), a truth predicate is defined for an object-language. This definition is carried out in a metalanguage, which is typically taken to include set theory or another strong theory or expressive language. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1) | |
| A reaction: Presumably the metalanguage includes set theory because that connects it with mathematics, and enables it to be formally rigorous. Tarski showed, in his undefinability theorem, that the meta-language must have increased resources. |
| 15655 | Should axiomatic truth be 'conservative' - not proving anything apart from implications of the axioms? [Halbach] |
| Full Idea: If truth is not explanatory, truth axioms should not allow proof of new theorems not involving the truth predicate. It is hence said that axiomatic truth should be 'conservative' - not implying further sentences beyond what the axioms can prove. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.3) | |
| A reaction: [compressed] |
| 15654 | If truth is defined it can be eliminated, whereas axiomatic truth has various commitments [Halbach] |
| Full Idea: If truth can be explicitly defined, it can be eliminated, whereas an axiomatized notion of truth may bring all kinds of commitments. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.3) | |
| A reaction: The general principle that anything which can be defined can be eliminated (in an abstract theory, presumably, not in nature!) raises interesting questions about how many true theories there are which are all equivalent to one another. |
| 15650 | Axiomatic theories of truth need a weak logical framework, and not a strong metatheory [Halbach] |
| Full Idea: Axiomatic theories of truth can be presented within very weak logical frameworks which require very few resources, and avoid the need for a strong metalanguage and metatheory. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1) |
| 15648 | Instead of a truth definition, add a primitive truth predicate, and axioms for how it works [Halbach] |
| Full Idea: The axiomatic approach does not presuppose that truth can be defined. Instead, a formal language is expanded by a new primitive predicate of truth, and axioms for that predicate are then laid down. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1) | |
| A reaction: Idea 15647 explains why Halbach thinks the definition route is no good. |
| 15656 | Deflationists say truth merely serves to express infinite conjunctions [Halbach] |
| Full Idea: According to many deflationists, truth serves merely the purpose of expressing infinite conjunctions. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.3) | |
| A reaction: That is, it asserts sentences that are too numerous to express individually. It also seems, on a deflationist view, to serve for anaphoric reference to sentences, such as 'what she just said is true'. |
| 15657 | To prove the consistency of set theory, we must go beyond set theory [Halbach] |
| Full Idea: The consistency of set theory cannot be established without assumptions transcending set theory. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 2.1) |
| 15652 | We can use truth instead of ontologically loaded second-order comprehension assumptions about properties [Halbach] |
| Full Idea: The reduction of 2nd-order theories (of properties or sets) to axiomatic theories of truth may be conceived as a form of reductive nominalism, replacing existence assumptions (for comprehension axioms) by ontologically innocent truth assumptions. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.1) | |
| A reaction: I like this very much, as weeding properties out of logic (without weeding them out of the world). So-called properties in logic are too abundant, so there is a misfit with their role in science. |
| 15651 | Instead of saying x has a property, we can say a formula is true of x - as long as we have 'true' [Halbach] |
| Full Idea: Quantification over (certain) properties can be mimicked in a language with a truth predicate by quantifying over formulas. Instead of saying that Tom has the property of being a poor philosopher, we can say 'x is a poor philosopher' is true of Tom. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.1) | |
| A reaction: I love this, and think it is very important. He talks of 'mimicking' properties, but I see it as philosophers mistakenly attributing properties, when actually what they were doing is asserting truths involving certain predicates. |
| 15200 | How could change consist of a conjunction of changeless facts? [McTaggart, by Le Poidevin] |
| Full Idea: McTaggart objects, to Russell 1903, that change cannot consist of a conjunction of changeless facts. | |
| From: report of J.M.E. McTaggart (The Nature of Existence vol.2 [1927]) by Robin Le Poidevin - Past, Present and Future of Debate about Tense 1 (b) | |
| A reaction: I agree with McTaggart. Logicians like to model processes with domains of timeless entities, but it just won't do. |
| 14761 | Change is not just having two different qualities at different points in some series [McTaggart] |
| Full Idea: The fact that it is hot at one point in a series and cold at other points cannot give change, if neither of these facts change. If two points on a line have different properties, this doesn't give change. | |
| From: J.M.E. McTaggart (The Nature of Existence vol.2 [1927], 33.315-6), quoted by Theodore Sider - Four Dimensionalism 6.2 | |
| A reaction: [The second half compresses an example about the Meridian] This objection is aimed at Russell's view, that change is just different properties at different times. I (unlike Sider) am wholly with McTaggart on this one. Change is 'dynamic'. |
| 20429 | Most of us are too close to our own motives to understand them [Fry] |
| Full Idea: The motives we actually experience are too close to us to enable us to feel them clearly. They are in a sense unintelligible. | |
| From: Roger Fry (An Essay in Aesthetics [1909], p.30) | |
| A reaction: Fry is defending the role of art in clarifying and highlighting such things, but I am not convinced by his claim. We can grasp most of our motives with a little introspection, and those we can't grasp are probably too subtle for art as well. |
| 20424 | Imaginative life requires no action, so new kinds of perception and values emerge in art [Fry] |
| Full Idea: In the imaginative life no action is necessary, so the whole consciousness may be focused upon the perceptive and the emotional aspects of the experience. Hence we get a different set of values, and a different kind of perception | |
| From: Roger Fry (An Essay in Aesthetics [1909], p.24) | |
| A reaction: Good. A huge range of human activities are like scientific experiments, where you draw on our evolved faculties, but put them in controlled conditions, where the less convenient and stressful parts are absent. War and sport. Real and theatrical tragedy. |
| 20427 | Everyone reveals an aesthetic attitude, looking at something which only exists to be seen [Fry] |
| Full Idea: It is only when an object exists for no other purpose than to be seen that we really look at it, …and then even the most normal person adopts to some extent the artistic attitude of pure vision abstracted from necessity. | |
| From: Roger Fry (An Essay in Aesthetics [1909], p.29) | |
| A reaction: A painter of still life looks at things which exist for other purposes, with just the attitude which Fry attributes to the viewers of the paintings. We can encourage a child to look at a flower with just this attitude. |
| 20433 | 'Beauty' can either mean sensuous charm, or the aesthetic approval of art (which may be ugly) [Fry] |
| Full Idea: There is an apparent contradiction between two distinct uses of the word 'beauty', one for that which has sensuous charm, and one for the aesthetic approval of works of imaginative art where the objects presented to us are often of extreme ugliness. | |
| From: Roger Fry (An Essay in Aesthetics [1909], p.33) | |
| A reaction: The gouging of eyes in 'King Lear' was always the big problem case for aesthetics, just as nowadays it is Marcel Duchamp's wretched 'Fountain'. |
| 20430 | In life we neglect 'cosmic emotion', but it matters, and art brings it to the fore [Fry] |
| Full Idea: Those feelings unhappily named cosmic emotion find almost no place in life, but, since they seem to belong to certain very deep springs of our nature, do become of great importance in the arts. | |
| From: Roger Fry (An Essay in Aesthetics [1909], p.31) | |
| A reaction: Focus on the sublime was big in the romantic era, but Fry still sees its importance, and I don't think it ever goes away. Art styles which scorn the sublime are failing to perform their social duty, say I. |
| 20431 | Art needs a mixture of order and variety in its sensations [Fry] |
| Full Idea: The first quality that we demand in our [artistic] sensations will be order, without which our sensations will be troubled and perplexed, and the other will be variety, without which they will not be fully stimulated. | |
| From: Roger Fry (An Essay in Aesthetics [1909], p.32) | |
| A reaction: He makes good claims, but gives unconvincing reasons for them. Some of us rather like 'troubled and perplexed' sensations. And a very narrow range of sensations could still be highly stimulated. Is Fry a good aesthetician but a modest philosopher? |
| 20423 | If graphic arts only aim at imitation, their works are only trivial ingenious toys [Fry] |
| Full Idea: If imitation is the sole purpose of the graphic arts, it is surprising that the works of such arts are ever looked upon as more than curiosities, or ingenious toys, and are ever taken seriously by grown-up people. | |
| From: Roger Fry (An Essay in Aesthetics [1909], p.23) | |
| A reaction: But then you might say that same about fine wines. A mere nice taste is hardly worthy of grown ups, and yet lots of grown ups feeling quite passionately about it. What about Fabergé eggs? |
| 20428 | Popular opinion favours realism, yet most people never look closely at anything! [Fry] |
| Full Idea: Ordinary people have almost no idea of what things really look like, so that the one standard that popular criticism applies to painting (whether it is like nature or not) is the one which most people are prevented frm applying properly. | |
| From: Roger Fry (An Essay in Aesthetics [1909], p.29) | |
| A reaction: A nice remark, though there is a streak of Bloomsbury artistic snobbery running through Fry. Ordinary people recognise photographic realism, so they can study things closely either in the reality or the picture, should they so choose. |
| 20432 | When viewing art, rather than flowers, we are aware of purpose, and sympathy with its creator [Fry] |
| Full Idea: In our reaction to a work of art (rather than a flower) there is the consciousness of purpose, of a peculiar relation of sympathy with the man who made this thing in order to arouse precisely the sensations we experience. | |
| From: Roger Fry (An Essay in Aesthetics [1909], p.33) | |
| A reaction: I think this is entirely right. I like the mention of 'sympathy' as well as 'purpose'. |
| 20425 | In the cinema the emotions are weaker, but much clearer than in ordinary life [Fry] |
| Full Idea: One notices in the visions of the cinematograph that whatever emotions are aroused by them, though they are likely to be weaker than those of ordinary life, are presented more clearly to the conscious. | |
| From: Roger Fry (An Essay in Aesthetics [1909], p.25) | |
| A reaction: Fry had probably only seen very simple melodramas, but the general idea that artistic emotions are weaker than real life, but much clearer, is quite plausible. |
| 20426 | For pure moralists art must promote right action, and not just be harmless [Fry] |
| Full Idea: To the pure moralist, accepting nothing but ethical values, to be justified, the life of the imagination must be shown not only not to hinder but actually to forward right action, otherwise it is not only useless but, by absorbing energies, harmful. | |
| From: Roger Fry (An Essay in Aesthetics [1909], p.26) | |
| A reaction: I think this is the sort of attitude you find in Samuel Johnson. Puritans even reject light music, which seems pleasantly harmless to the rest of us. 'Absorbing energies' doesn't sound much of an objection, and may not be the actual objection. |
| 2608 | For McTaggart time is seen either as fixed, or as relative to events [McTaggart, by Ayer] |
| Full Idea: McTaggart says we can speak of events in time in two ways, as past, present or future, or as being before or after or simultaneous with one another. The first cannot be reduced to the second, as the second makes no provision for the passage of time. | |
| From: report of J.M.E. McTaggart (The Nature of Existence vol.2 [1927], II.329-) by A.J. Ayer - The Central Questions of Philosophy 1.D |
| 22936 | A-series time positions are contradictory, and yet all events occupy all of them! [McTaggart, by Le Poidevin] |
| Full Idea: McTaggart's proof of time's unreality: A-series positions (past, present and future) are mutually incompatible, so no event can exhibit more than one of them; but since A-series events change position, all events have all A-series posititions. Absurd! | |
| From: report of J.M.E. McTaggart (The Nature of Existence vol.2 [1927]) by Robin Le Poidevin - Travels in Four Dimensions 08 'McTaggart's' | |
| A reaction: I'm not convinced that this is any more contradictory than someone being married at one time and unmarried at another. No one is suggesting that an A-series event can be both past and future simultaneously. |
| 4231 | Time involves change, only the A-series explains change, but it involves contradictions, so time is unreal [McTaggart, by Lowe] |
| Full Idea: McTaggart argued that time involves change, only the A-series can explain change, the A-series involves contradictions (past, present and future), and hence time is unreal. | |
| From: report of J.M.E. McTaggart (The Nature of Existence vol.2 [1927]) by E.J. Lowe - A Survey of Metaphysics p.313 | |
| A reaction: I doubt whether it is a logical contradiction to say Waterloo has been past, present and future, though it is odd. |
| 8591 | There could be no time if nothing changed [McTaggart] |
| Full Idea: It is universally admitted.... that there could be no time if nothing changed. | |
| From: J.M.E. McTaggart (The Nature of Existence vol.2 [1927], II p.11), quoted by Sydney Shoemaker - Time Without Change p.49 | |
| A reaction: This is set up alongside Aristotle (Idea 8590) to be attacked by Shoemaker. I think Shoemaker is right, and that the rejection of McTaggart's view is a key result in modern metaphysics. |
| 22935 | The B-series can be inferred from the A-series, but not the other way round [McTaggart, by Le Poidevin] |
| Full Idea: McTaggart says the A-series is more fundamental than the B-series. An objective being could not deduce the present moment of the A-series from the B-series, but the B-series can be deduced from the A-series. | |
| From: report of J.M.E. McTaggart (The Nature of Existence vol.2 [1927]) by Robin Le Poidevin - Travels in Four Dimensions 08 'McTaggart's' | |
| A reaction: [summarised] This has no ontological importance for McTaggart, since he thinks time is unreal either way. But giving the A-series priority because it reveals the present moment seems to nullify the B-series as incomplete. |
| 7802 | A-series uses past, present and future; B-series uses 'before' and 'after' [McTaggart, by Girle] |
| Full Idea: The A-series puts events into past, present and future. The B-series puts events into a series based on relationships of 'before' and 'after'. McTaggart said the A-series was contradictory, and the B-series failed to cope with essential features of time. | |
| From: report of J.M.E. McTaggart (The Nature of Existence vol.2 [1927]) by Rod Girle - Modal Logics and Philosophy 8.10 | |
| A reaction: The A-series is indexical. |
| 4230 | A-series expressions place things in time, and their truth varies; B-series is relative, and always true [McTaggart, by Lowe] |
| Full Idea: A-series expressions include words like 'today' and 'five weeks ago', and can be true at one time and false at another; B-series expressions are like 'simultaneously', and are always true, if true at all. | |
| From: report of J.M.E. McTaggart (The Nature of Existence vol.2 [1927]) by E.J. Lowe - A Survey of Metaphysics p.308 | |
| A reaction: A-series gives time separate existence, where B-series time is purely relational. Intuition favours the A-series, but how fast do events travel against this fixed background? |
| 15199 | The B-series must depend on the A-series, because change must be explained [McTaggart, by Le Poidevin] |
| Full Idea: McTaggart's argument is 1) B-series relations are temporal relations, 2) There cannot be temporal relations unless there is change, 3) There cannot be change unless there is real A-series ordering, so there can't be a B-series unless there is an A-series. | |
| From: report of J.M.E. McTaggart (The Nature of Existence vol.2 [1927], vol.ii) by Robin Le Poidevin - Past, Present and Future of Debate about Tense 1 a |