50 ideas
| 18390 | All metaphysical discussion should be guided by a quest for truthmakers [Armstrong] |
| Full Idea: My plea, whatever conclusions are drawn, is to control the metaphysical discussion by continual reference to suggested truthmakers. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 08.7) | |
| A reaction: ...And my plea is to control metaethical discussion by continual reference to value-makers. In general, this is the approach which will deliver a unified account of the world. Truthmakers are the ideal restraint on extravagant metaphysics. |
| 10633 | 'Some critics admire only one another' cannot be paraphrased in singular first-order [Linnebo] |
| Full Idea: The Geach-Kaplan sentence 'Some critics admire only one another' provably has no singular first-order paraphrase using only its predicates. | |
| From: Øystein Linnebo (Plural Quantification [2008], 1) | |
| A reaction: There seems to be a choice of either going second-order (picking out a property), or going plural (collectively quantifying), or maybe both. |
| 18467 | Truth-making can't be entailment, because truthmakers are portions of reality [Armstrong] |
| Full Idea: Truth-making cannot be any form of entailment. Both terms of an entailment relation must be propositions, but the truth-making term of the truth-making relation is a portion of reality, and, in general at least, portions of reality are not propositions. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 02.3) | |
| A reaction: Along with Idea 18466, that seems to firmly demolish the idea that truth-making is a logical entailment. |
| 18468 | Armstrong says truthmakers necessitate their truth, where 'necessitate' is a primitive relation [Armstrong, by MacBride] |
| Full Idea: In a bold manouevre Armstrong posited a metaphysically primitive relation of necessitation, and then defined truth-makers in terms of this bridging relation, as a thing that necessitates something being true. | |
| From: report of David M. Armstrong (Truth and Truthmakers [2004], 02.3) by Fraser MacBride - Truthmakers 1.2 | |
| A reaction: [Not sure of page reference] Spelled out so clearly by MacBride, this sounds dubious. How many truths are necessitated by the City of London? Do truthmakers necessitate the existence of their truths? MacBride says it's a circular theory. |
| 18377 | Negative truths have as truthmakers all states of affairs relevant to the truth [Armstrong] |
| Full Idea: Postulate a higher-order state of affairs, of all the states of affairs in which Theaetetus is involved. Is this not a good candidate for a truthmaker for the negative truth that 'Theaetetus is not flying'? | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 05.2) | |
| A reaction: It certainly seems extravagant to need the whole universe to make true 'there are no lions in this room'. But for 'there are no unicorns' it is not clear which states of affairs unicorns are involved. (Armstrong is aware of this). |
| 18382 | The nature of arctic animals is truthmaker for the absence of penguins there [Armstrong] |
| Full Idea: Each of the arctic animals is by its nature different from a penguin, so this general state of affairs seems truthmaker enough for this negative existential. Similarly, the totality of all birds eliminates the phoenix. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 06.2) | |
| A reaction: Why is it 'animals' in one case, and 'birds' in the other? What if there was no life in arctic? Would the snow then do the job? This doesn't seem to work. |
| 18394 | In mathematics, truthmakers are possible instantiations of structures [Armstrong] |
| Full Idea: A mathematical entity exists if and only if it is possible that there be instantiations of that structure. This transforms the question of truthmakers for the existence of mathematical entities into a question of truthmakers for certain possibilities. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 09.3) | |
| A reaction: This modal approach to structuralism [for which he endorses Hellman 1989] opens up a modal approach to other truthmakers, which places dispositions at the centre of physical truthmaking. No sets of Meinongian objects? |
| 18384 | One truthmaker will do for a contingent truth and for its contradictory [Armstrong] |
| Full Idea: It seems reasonable to say that a truthmaker for a contingent truth is also a truthmaker for the truth that the contradictory of that truth is possible. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 07.2) | |
| A reaction: The truthmaker will have to be not only some fact, but also the additional fact that it is contingent, in order to generate the possibility of the contradictory. |
| 18387 | The truthmakers for possible unicorns are the elements in their combination [Armstrong] |
| Full Idea: The obvious minimal truthmaker for the truth that 'it is possible that a unicorn exists' is combinatorial. The elements of the combination are all that is needed. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 07.5) | |
| A reaction: This seems to imply that there are no possibilities which are not combinations of what currently exists. |
| 18386 | What is the truthmaker for 'it is possible that there could have been nothing'? [Armstrong] |
| Full Idea: It is possible that there could have been nothing. ...What would be its truthmaker? | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 07.4) | |
| A reaction: I suppose the truthmaker here is the whole of reality, with its dispositions and contingencies. But that won't do for 'possibly there might never have been anything'. In such a case there wouldn't be any truths. |
| 18381 | Necessitating general truthmakers must also specify their limits [Armstrong] |
|
Full Idea:
The mereological sum of what happens to be all the men does not necessitate that it is all the men. So if truthmaking involves necessitation, then this object cannot be the complete truthmaker for |
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| From: David M. Armstrong (Truth and Truthmakers [2004], 06.1) | |
| A reaction: [He invokes Russell has his source] His point is that the truthmaker needs a further fact, beyond the men, which specifies that this is all of them. But only if truthmakers necessitate their truths (as Armstrong claims). I'm sympathetic to both claims. |
| 18396 | The set theory brackets { } assert that the member is a unit [Armstrong] |
| Full Idea: The idea is that braces { } attribute to an entity the place-holding, or perhaps determinable, property of unithood. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 09.5) | |
|
A reaction:
I like this. There is Socrates himself, then there is my concept |
| 18393 | For 'there is a class with no members' we don't need the null set as truthmaker [Armstrong] |
|
Full Idea:
The null class is useful in formal set theory, but I hope that does not require that there be a thing called the null class which is truthmaker for the strange proposition |
|
| From: David M. Armstrong (Truth and Truthmakers [2004], 09.1) | |
| A reaction: It is not quite clear why it doesn't, but then it is not quite clear to philosophers what the status of the null set is, in comparison with sets that have members. |
| 10638 | A pure logic is wholly general, purely formal, and directly known [Linnebo] |
| Full Idea: The defining features of a pure logic are its absolute generality (the objects of discourse are irrelevant), and its formality (logical truths depend on form, not matter), and its cognitive primacy (no extra-logical understanding is needed to grasp it). | |
| From: Øystein Linnebo (Plural Quantification [2008], 3) | |
| A reaction: [compressed] This strikes me as very important. The above description seems to contain no ontological commitment at all, either to the existence of something, or to two things, or to numbers, or to a property. Pure logic seems to be 'if-thenism'. |
| 18739 | Three stages of philosophical logic: syntactic (1905-55), possible worlds (1963-85), widening (1990-) [Horsten/Pettigrew] |
| Full Idea: Three periods can be distinguished in philosophical logic: the syntactic stage, from Russell's definite descriptions to the 1950s, the dominance of possible world semantics from the 50s to 80s, and a current widening of the subject. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 1) | |
| A reaction: [compressed] I've read elsewhere that the arrival of Tarski's account of truth in 1933, taking things beyond the syntactic, was also a landmark. |
| 18741 | Logical formalization makes concepts precise, and also shows their interrelation [Horsten/Pettigrew] |
| Full Idea: Logical formalization forces the investigator to make the central philosophical concepts precise. It can also show how some philosophical concepts and objects can be defined in terms of others. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 2) | |
| A reaction: This is the main rationale of the highly formal and mathematical approach to such things. The downside is when you impose 'precision' on language that was never intended to be precise. |
| 10640 | Instead of complex objects like tables, plurally quantify over mereological atoms tablewise [Linnebo] |
| Full Idea: Plural quantification can be used to eliminate the commitment of science and common sense to complex objects. We can use plural quantification over mereological atoms arranged tablewise or chairwise. | |
| From: Øystein Linnebo (Plural Quantification [2008], 4.5) | |
| A reaction: [He cites Hossack and van Ingwagen] |
| 10636 | Plural plurals are unnatural and need a first-level ontology [Linnebo] |
| Full Idea: Higher-order plural quantification (plural plurals) is often rejected because plural quantification is supposedly ontological innocent, with no plural things to be plural, and because it is not found in ordinary English. | |
| From: Øystein Linnebo (Plural Quantification [2008], 2.4) | |
| A reaction: [Summary; he cites Boolos as a notable rejector] Linnebo observes that Icelandic contains a word 'tvennir' which means 'two pairs of'. |
| 10639 | Plural quantification may allow a monadic second-order theory with first-order ontology [Linnebo] |
| Full Idea: Plural quantification seems to offer ontological economy. We can pay the price of a mere first-order theory and then use plural quantification to get for free the corresponding monadic second-order theory, which would be an ontological bargain. | |
| From: Øystein Linnebo (Plural Quantification [2008], 4.4) | |
| A reaction: [He mentions Hellman's modal structuralism in mathematics] |
| 10635 | Second-order quantification and plural quantification are different [Linnebo] |
| Full Idea: Second-order quantification and plural quantification are generally regarded as different forms of quantification. | |
| From: Øystein Linnebo (Plural Quantification [2008], 2) |
| 10641 | Traditionally we eliminate plurals by quantifying over sets [Linnebo] |
| Full Idea: The traditional view in analytic philosophy has been that all plural locutions should be paraphrased away by quantifying over sets, though Boolos and other objected that this is unnatural and unnecessary. | |
| From: Øystein Linnebo (Plural Quantification [2008], 5) |
| 18744 | Models are sets with functions and relations, and truth built up from the components [Horsten/Pettigrew] |
| Full Idea: A (logical) model is a set with functions and relations defined on it that specify the denotation of the non-logical vocabulary. A series of recursive clauses explicate how truth values of complex sentences are compositionally determined from the parts. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 3) | |
| A reaction: See the ideas on 'Functions in logic' and 'Relations in logic' (in the alphabetical list) to expand this important idea. |
| 18392 | Classes have cardinalities, so their members must all be treated as units [Armstrong] |
| Full Idea: Classes, because they have a particular cardinality, are essentially a certain number of ones, things that, within the particular class, are each taken as a unit. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 09.1) | |
| A reaction: [Singletons are exceptions] So units are basic to set theory, which is the foundations of technical analytic philosophy (as well as, for many, of mathematics). If you can't treat something as a unit, it won't go into set theory. Vagueness... |
| 18740 | If 'exist' doesn't express a property, we can hardly ask for its essence [Horsten/Pettigrew] |
| Full Idea: If there is indeed no property of existence that is expressed by the word 'exist', then it makes no sense to ask for its essence. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 2) | |
| A reaction: As far as I can tell, this was exactly Aristotle's conclusion, so he skirted round the question of 'being qua being', and focused on the nature of objects instead. Grand continental talk of 'Being' doesn't sound very interesting. |
| 18385 | Logical atomism builds on the simple properties, but are they the only possible properties? [Armstrong] |
| Full Idea: One of the assumptions of logical atomism is that all structural properties, all complex properties, are composed of simple properties and relations. ...But does the totality of the simple properties consist of the only possible simple properties? | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 07.3) | |
| A reaction: This refers to what Lewis calls 'alien' properties - possible properties that cannot even be constructed from actual properties. Armstrong's question is about the truthmakers for such things. A bit speculative... |
| 18391 | 'Naturalism' says only the world of space-time exists [Armstrong] |
| Full Idea: I define 'naturalism' as the hypothesis that the world of space-time is all that there is. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 09.1) | |
| A reaction: This is helpful, because it doesn't mention the nature of the physical matter contained in space-time, leaving theories like panpsychism as possible naturalistic theories. Galen Strawson, for example. |
| 18374 | Truthmaking needs states of affairs, to unite particulars with tropes or universals. [Armstrong] |
| Full Idea: There must exist states of affairs as truthmakers, to get us beyond 'loose and separate' entities. ...They can be bundles of tropes, or trope-with-particular, or bundles of universals ('compresence'), or instantiations. They are an addition to ontology. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 04.5) | |
| A reaction: Armstrong is the great champion of states of affairs. They seem rather vague to me, and disconcertingly timeless. |
| 10643 | We speak of a theory's 'ideological commitments' as well as its 'ontological commitments' [Linnebo] |
| Full Idea: Some philosophers speak about a theory's 'ideological commitments' and not just about its 'ontological commitments'. | |
| From: Øystein Linnebo (Plural Quantification [2008], 5.4) | |
| A reaction: This is a third strategy for possibly evading one's ontological duty, along with fiddling with the words 'exist' or 'object'. An ideological commitment to something to which one is not actually ontologically committed conjures up stupidity and dogma. |
| 10637 | Ordinary speakers posit objects without concern for ontology [Linnebo] |
| Full Idea: Maybe ordinary speakers aren't very concerned about their ontological commitments, and sometimes find it convenient to posit objects. | |
| From: Øystein Linnebo (Plural Quantification [2008], 2.4) | |
| A reaction: I think this is the whole truth about the ontological commitment of ordinary language. We bring abstraction under control by pretending it is a world of physical objects. The 'left wing' in politics, 'dark deeds', a 'huge difference'. |
| 18372 | We need properties, as minimal truthmakers for the truths about objects [Armstrong] |
| Full Idea: The 'thing itself' seems not be a minimal truthmaker for the thing having its particular mass. ...The thing has a great many other properties. ...It seems entirely reasonable to postulate that the object has properties that are objectively there. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 04.2) | |
| A reaction: This is Armstrong using the truthmaker principle to argue for the existence of properties (as instantiated universals). I like truthmakers, but truths do not have enough precision in their parts for us to read off reality from them. |
| 18379 | The determinates of a determinable must be incompatible with each other [Armstrong] |
| Full Idea: A set of determinates under the one determinable are incompatible by definition. If an object is not one mile in length, then its actual length will be incompatible with being one mile in length. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 05.2.1) | |
| A reaction: This is a much better general version of the standard example 'if it is red it can't be green'. Armstrong uses it to give a more precise account of incompatibility. Useful. |
| 18378 | Length is a 'determinable' property, and one mile is one its 'determinates' [Armstrong] |
| Full Idea: Length is a 'determinable' property; being some particular length, such as a mile, is one of its 'determinates'. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 05.2.1) | |
| A reaction: The seem to be 'type' and 'token' properties, except that this other vocabulary indicates the link between them. |
| 18373 | If tropes are non-transferable, then they necessarily belong to their particular substance [Armstrong] |
| Full Idea: 'Non-transferable' theories of tropes hold that the mass is of this stone by necessity. It is an identity condition for the property. Every property then becomes an essential property. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 04.3) | |
| A reaction: [He cites Martin and Heil for this view] It is hard to see in this proposal how the trope is in any way separate from its substance, and hence it seems a bit of a vacuous theory. (The other theories of properties aren't much cop either). |
| 18400 | Properties are not powers - they just have powers [Armstrong] |
| Full Idea: Properties are not powers. But properties have powers. They bestow powers. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 10.4) | |
| A reaction: I think this is the wrong way round. In this view, powers become extremely vague things, ranging from the fine-grained to the hugely broad. It seems to me that powers are precise and real, but properties are the vague unhelpful things. |
| 18397 | Powers must result in some non-powers, or there would only be potential without result [Armstrong] |
| Full Idea: Powers must surely issue in manifestations that are something more than just powers. A world where potency never issued in act, but only in more potency, would be one where one travelled without ever having the possibility of arriving. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 10.4) | |
| A reaction: Tricky. The picture I favour is that the distinction between powers and categorical properties is a misunderstanding. What is fundamental is active and powerful categoricals. |
| 18399 | How does the power of gravity know the distance it acts over? [Armstrong] |
| Full Idea: If masses are powers, the forces generated between two particulars have to vary inversely with the square of their distance apart. Have not the masses got to 'know' at what distance they are from each other, to exert the right amount of force? | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 10.4) | |
| A reaction: This seems like a good warning against a simplistic account of powers doing all the work, but I suspect that more sophisticated physics would offer the fan of powers a solution here. The power is to 'spread' the force around. |
| 18371 | The class of similar things is much too big a truthmaker for the feature of a particular [Armstrong] |
| Full Idea: For a Class Nominalist 'the class of all 4-kilo objects' is the truthmaker for the truth that the particular has just that mass. Yet this looks far too big! Would not the object still be four kilos even if the other members of the class had never existed? | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 04.2) | |
| A reaction: This seems so obvious to me as to be hardly worth saying. To identify redness with the class of red entities just seems crazy. Why do they belong in that class? Armstrong is illustrating the value of the truthmaker idea in philosophy. |
| 18389 | When entities contain entities, or overlap with them, there is 'partial' identity [Armstrong] |
| Full Idea: There is 'partial identity' where one entity contains another with something to spare, or else where entities overlap each other. ...Extensive quantities, such as length and mass, are the particularly plausible cases. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 08.5) | |
| A reaction: This looks like a very useful concept which deserves wider use. It will help discussions of rivers, statues, intersecting roads etc. |
| 18745 | A Tarskian model can be seen as a possible state of affairs [Horsten/Pettigrew] |
| Full Idea: A Tarskian model can in a sense be seen as a model of a possible state of affairs. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 3) | |
| A reaction: I include this remark to show how possible worlds semantics built on the arrival of model theory. |
| 18747 | The 'spheres model' was added to possible worlds, to cope with counterfactuals [Horsten/Pettigrew] |
| Full Idea: The notion of a possible worlds model was extended (resulting in the concept of a 'spheres model') in order to obtain a satisfactory logical treatment of counterfactual conditional sentences. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 4) | |
| A reaction: Thus we add 'centred' worlds, and an 'actual' world, to the loose original model. It is important to remember when we discuss 'close' worlds that we are then committed to these presuppositions. |
| 18748 | Epistemic logic introduced impossible worlds [Horsten/Pettigrew] |
| Full Idea: The idea of 'impossible worlds' was introduced into epistemic logic. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 4) | |
| A reaction: Nathan Salmon seems interested in their role in metaphysics (presumably in relation to Meinongian impossible objects, like circular squares, which must necessarily be circular). |
| 18388 | Possible worlds don't fix necessities; intrinsic necessities imply the extension in worlds [Armstrong] |
| Full Idea: It seems natural and plausible to say that it is the fact that a necessary truth is itself necessary that determines its truth in all possible worlds. This intension determines its extension across possible worlds. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 08.1) | |
| A reaction: Well said. To me (but not to Armstrong) this implies essentialism, that the necessity arises from the intrinsic natures of the things involved. The whole Lewisian approach of explaining things by mapping them strikes me as wrong. |
| 18746 | Possible worlds models contain sets of possible worlds; this is a large metaphysical commitment [Horsten/Pettigrew] |
| Full Idea: Each possible worlds model contains a set of possible worlds. For this reason, possible worlds semantics is often charged with smuggling in heavy metaphysical commitments. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 3) | |
| A reaction: To a beginner it looks very odd that you should try to explain possibility by constructing a model of it in terms of 'possible' worlds. |
| 18750 | Using possible worlds for knowledge and morality may be a step too far [Horsten/Pettigrew] |
| Full Idea: When the possible worlds semantics were further extended to model notions of knowledge and of moral obligation, the application was beginning to look distinctly forced and artificial. | |
| From: Horsten,L/Pettigrew,R (Mathematical Methods in Philosophy [2014], 5) | |
| A reaction: They accept lots of successes in modelling necessity and time. |
| 18375 | General truths are a type of negative truth, saying there are no more ravens than black ones [Armstrong] |
| Full Idea: General truths are a species of negative truth, 'no more' truths, asserting that there are no more men than the mortal ones, no more ravens than the black ones. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 05.1) | |
| A reaction: He goes on to distinguish between 'absences' and 'limits' in this area. |
| 10634 | Predicates are 'distributive' or 'non-distributive'; do individuals do what the group does? [Linnebo] |
| Full Idea: The predicate 'is on the table' is 'distributive', since some things are on the table if each one is, whereas the predicate 'form a circle' is 'non-distributive', since it is not analytic that when some things form a circle, each one forms a circle. | |
| From: Øystein Linnebo (Plural Quantification [2008], 1.1) | |
| A reaction: The first predicate can have singular or plural subjects, but the second requires a plural subject? Hm. 'The rope forms a circle'. The second is example is not true, as well as not analytic. |
| 18368 | For all being, there is a potential proposition which expresses its existence and nature [Armstrong] |
| Full Idea: The thesis of 'expressibility' says that for all being, there is a proposition (perhaps one never formulated by any mind at any time) that truly renders the existence and nature of this being. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 02.3.2) | |
| A reaction: [He credits Stephen Read 2000:68-9 for this] Armstrong accepts this, but I deny it. I can't make any sense of this vast plethora of propositions, each exactly expressing some minute nuance of the infinity complexity of all being. |
| 18370 | A realm of abstract propositions is causally inert, so has no explanatory value [Armstrong] |
| Full Idea: We could not stand in any causal or nomic relation to a realm of propositions over and above the space-time world, ...so it is unclear that such a postulation is of any explanatory value. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 02.6) | |
| A reaction: I agree, and I like Armstrong's appeal to explanation as a criterion for whether we should make an ontological commitment here. I am baffled by anyone who thinks reality is crammed full of unarticulated propositions. Only a philosopher.... |
| 18380 | Negative causations supervene on positive causations plus their laws? [Armstrong] |
| Full Idea: Is it not very plausible that negative causations supervene on the positive causations together with the laws that govern the positive causations? | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 05.2.3) | |
| A reaction: This obviously has a naturalistic appeal, since all causation can then be based on the actual world. |
| 18401 | The pure present moment is too brief to be experienced [Armstrong] |
| Full Idea: The metaphysical present will be a strict instant, or, if time is not infinitely divisible, the present will be a minimum granule of duration. But strict instants or minimal granules of duration, if these exist, cannot be experienced. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 11) | |
| A reaction: He points out that this is ironic, since Presentism lies on the basic experience of the present. |