display all the ideas for this combination of philosophers
53 ideas
| 15751 | Surely 'slept in by Washington' is a property of some bed? [Lewis] |
| Full Idea: That the most noteworthy property of this bed is that George Washington slept in it - surely this is true on some legitimate conception of properties? | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: Wrong! This example is a nice clear test case. This is an absurd slippery slope. A bed he once looked at? I would have thought this was a relation the bed once entered into, and a relation isn't a property. |
| 8571 | Universals are wholly present in their instances, whereas properties are spread around [Lewis] |
| Full Idea: Universals and properties are different because a universal is supposed to be wholly present wherever it is instantiated. A property, by contrast, is spread around. The property of being a donkey is partly present wherever there is a donkey. | |
| From: David Lewis (New work for a theory of universals [1983], 'Un and Prop') | |
| A reaction: No mention of tropes. The claim that universals are widespread, and yet must be instantiated, is dealt with by Lewis's commitment to the existence of possible donkeys. |
| 15735 | Properties don't have degree; they are determinate, and things have varying relations to them [Lewis] |
| Full Idea: I have made no place for properties that admit of degree, so that things may have more or less of the same property. There are plain properties, and then there are relations to them. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: An interesting question, little discussed. Elsewhere, Lewis ascribes all vagueness to our inadequate predicates, rather than to the world, which I find quite persuasive. |
| 9656 | The 'abundant' properties are just any bizarre property you fancy [Lewis] |
| Full Idea: Properties are 'sparse' or 'abundant'. The abundant properties may be as extrinsic, as gruesomely gerrymandered, as miscellaneously disjunctive, as you please. They pay no heed to the qualitative joints, but carve things up every which way. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: This seems to be a logician's idea, which is needed for the notion of a set as pure extension, but it has very little to do with what I understand by the word 'property'. Better to call it a 'categorization'. E.g. filing George W. Bush under 'jackal'. |
| 15737 | To be a 'property' is to suit a theoretical role [Lewis] |
| Full Idea: To deserve the name of 'property' is to be suited to play the right theoretical role. It is wrong to speak of 'the' role associated with the word 'property', as if it were fully and uncontroversially settled. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: Once again I see a chicken-and-egg problem. Surely something has a theoretical role because of its intrinsic character, or its prior definition? How could you formulate a theory if you lacked properties? We don’t meet properties as gaps in theories. |
| 14979 | Being alone doesn't guarantee intrinsic properties; 'being alone' is itself extrinsic [Lewis, by Sider] |
| Full Idea: The property of 'being alone in the world' is an extrinsic property, even though it has had by an object that is alone in the world. | |
| From: report of David Lewis (Extrinsic Properties [1983]) by Theodore Sider - Writing the Book of the World 01.2 | |
| A reaction: I always choke on my cornflakes whenever anyone cites a true predicate as if it were a genuine property. This is a counterexample to Idea 14978. Sider offers another more elaborate example from Lewis. |
| 15454 | Extrinsic properties come in degrees, with 'brother' less extrinsic than 'sibling' [Lewis] |
| Full Idea: Properties may be more or less intrinsic; being a brother has more of an admixture of intrinsic structure than being a sibling does, yet both are extrinsic. | |
| From: David Lewis (Extrinsic Properties [1983], I) | |
| A reaction: I suppose the point is that a brother is intrinsically male - but then a sibling is intrinsically human. A totally extrinsic relation would be one between entities which shared virtually no categories of existence. |
| 15742 | A disjunctive property can be unnatural, but intrinsic if its disjuncts are intrinsic [Lewis] |
| Full Idea: A property can be unnatural by reason of disjunctiveness, as the property of being tripartite-or-liquid-or-cubical is, and it is intrinsic if its disjuncts are. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: This strikes me as being utterly, shockingly and disgracefully wrong. A disjunction can't possibly be a property. Can a person have the property of being 'fat or thin'? A disjunction offers candidates for properties, not the properties themselves. |
| 15397 | If a global intrinsic never varies between possible duplicates, all necessary properties are intrinsic [Cameron on Lewis] |
| Full Idea: Lewis defines a globally intrinsic property as one that never varies between duplicates across possible worlds. This has the immediate problem that any property that is necessarily had, or necessarily lacked, by every thing will be intrinsic. | |
| From: comment on David Lewis (On the Plurality of Worlds [1986], p.61-2) by Ross P. Cameron - Intrinsic and Extrinsic Properties 'Analysis' | |
| A reaction: [He also cites Langton and Lewis 1998] To me this is the sort of tangle you get into when you equate properties with predicates. The problem seems to concern necessary predicates (but those may not be necessary properties). |
| 15398 | Global intrinsic may make necessarily coextensive properties both intrinsic or both extrinsic [Cameron on Lewis] |
| Full Idea: If a globally intrinsic properties are those that never vary between duplicates across possible worlds, then necessarily coextensive properties will either be both intrinsic or both extrinsic. | |
| From: comment on David Lewis (On the Plurality of Worlds [1986], p.61-2) by Ross P. Cameron - Intrinsic and Extrinsic Properties 'Analysis' | |
| A reaction: Presumably this problem would arise if some intrinsic property entailed an extrinsic property (or, less likely, vice versa). These sorts of problems arise when you try to define everything extensionally (even across possible worlds). |
| 15435 | If you think universals are immanent, you must believe them to be sparse, and not every related predicate [Lewis] |
| Full Idea: Any theorist of universals as immanent had better hold a sparse theory; it is preposterous on its face that a thing has as many nonspatiotemporal parts as there are different predicates that it falls under, or different classes that it belongs to. | |
| From: David Lewis (Against Structural Universals [1986], 'Why believe') | |
| A reaction: I am firmly committed to sparse universal, and view the idea that properties are just predicates as the sort of nonsense that results from approaching philosophy too linguistically. |
| 15400 | We must avoid circularity between what is intrinsic and what is natural [Lewis, by Cameron] |
| Full Idea: Lewis revised his analysis of duplication because he had assumed that as a matter of necessity perfectly natural properties are intrinsic, and that necessarily how a thing is intrinsically is determined completely by the natural properties it has. | |
| From: report of David Lewis (Defining 'Intrinsic' (with Rae Langton) [1998]) by Ross P. Cameron - Intrinsic and Extrinsic Properties 'Analysis' | |
| A reaction: [This compares Lewis 1986:61 with Langton and Lewis 1998] I am keen on both intrinsic and on natural properties, but I have not yet confronted this little problem. Time for a displacement activity, I think.... |
| 15458 | A property is 'intrinsic' iff it can never differ between duplicates [Lewis] |
| Full Idea: A property is 'intrinsic' iff it never can differ between duplicates; iff whenever two things (actual or possible) are duplicates, either both of them have the property or both of them lack it. | |
| From: David Lewis (Defining 'Intrinsic' (with Rae Langton) [1998], IV) | |
| A reaction: This leaves me wondering how one could arrive at a precise definition of 'duplicates'. Can it be done without mentioning that they have the same intrinsic properties? |
| 15459 | Ellipsoidal stars seem to have an intrinsic property which depends on other objects [Lewis] |
| Full Idea: The property of being an ellipsoidal star would seem offhand to be a basic intrinsic property, but it is incompatible (nomologically) with being an isolated object. | |
| From: David Lewis (Defining 'Intrinsic' (with Rae Langton) [1998], V) | |
| A reaction: Another nice example from Lewis. It makes you wonder whether the intrinsic/extrinsic distinction should go. Modern physics, with its 'entanglements', doesn't seem to suit the distinction. |
| 15741 | All of the natural properties are included among the intrinsic properties [Lewis] |
| Full Idea: It cannot be said that all intrinsic properties are perfectly natural, ...but it can plausibly be said that all perfectly natural properties are intrinsic. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: Idea 15742 give the example he uses to support this claim. I like the concept of 'intrinsic' properties, but cannot currently see any use for the concept of 'natural' ones. |
| 15752 | We might try defining the natural properties by a short list of them [Lewis] |
| Full Idea: We might try defining the natural properties by a short list, of the mass properties, charge properties, quark properties and flavours... | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5 n47) | |
| A reaction: He rejects this because of possible natural properties in other possible worlds. Defining anything by a list seems like cheating. Does John, Paul, George and Ringo 'define' something? |
| 10717 | Natural properties figure in the analysis of similarity in intrinsic respects [Lewis, by Oliver] |
| Full Idea: Lewis argues that there are natural properties, which makes various analyses possible, especially of similarity in intrinsic respects. Naturalness comes in degrees, with perfectly natural properties being the limiting case. | |
| From: report of David Lewis (New work for a theory of universals [1983]) by Alex Oliver - The Metaphysics of Properties 4 | |
| A reaction: This sounds to be the wrong way round. We don't start with similarities and work back to natural properties. We encounter natural properties (through their causal action), and these give rise to the similarities. |
| 16217 | Lewisian natural properties fix reference of predicates, through a principle of charity [Lewis, by Hawley] |
| Full Idea: For Lewis natural properties are important for their role in making language and thought determinate: principles of charity or humanity tell us to attribute natural properties to predicates wherever possible, break underdetermination of their reference. | |
| From: report of David Lewis (New work for a theory of universals [1983]) by Katherine Hawley - How Things Persist 3.8 | |
| A reaction: Lewis always seems to find reasons in semantics or logic for his metaphysics, instead of in the science. Lewis ends up with 'folk' natural properties, instead of accurate ones. |
| 8613 | Objects are demarcated by density and chemistry, and natural properties belong in what is well demarcated [Lewis] |
| Full Idea: Where my cat (Bruce) ends, there the density of matter, the relative abundance of chemical elements, abruptly change. Bruce is also a locus of causal chains, which traces back to natural properties. Natural properties belong to well demarcated things. | |
| From: David Lewis (New work for a theory of universals [1983], 'Cont of L') | |
| A reaction: This is an amazingly convoluted way to define natural properties in terms of the classes they generate, but it seems obvious to me that the properties are logically prior to the classes. |
| 8585 | Reference partly concerns thought and language, partly eligibility of referent by natural properties [Lewis] |
| Full Idea: Reference consists in part of what we do in language or thought when we refer, but in part it consists in eligibility of the referent. And this eligibility to be referred to is a matter of natural properties. | |
| From: David Lewis (New work for a theory of universals [1983], 'Cont of L') | |
| A reaction: This is a surprising conclusion for Lewis to reach, having started from properties as any old set members (see Idea 8572). There are references to intentional objects, such as 'there should have been someone on duty'. |
| 8586 | Natural properties tend to belong to well-demarcated things, typically loci of causal chains [Lewis] |
| Full Idea: One thing that makes for naturalness of a property is that it is a property belonging exclusively to well-demarcated things (like my cat Bruce, who is a locus of causal chains). | |
| From: David Lewis (New work for a theory of universals [1983], 'Cont of L') | |
| A reaction: Compare Idea 8557. Well-demarcated things may also have gerrymandered properties that are parts of 'arbitrary Boolean compounds' (Lewis). Why not make use of the causal chains to identify the properties? |
| 8589 | For us, a property being natural is just an aspect of its featuring in the contents of our attitudes [Lewis] |
| Full Idea: The reason natural properties feature in the contents of our attitudes is that naturalness is part of what it is to feature therein. We aren't built to take a special interest in natural properties, or that we call them natural if they are interesting. | |
| From: David Lewis (New work for a theory of universals [1983], 'Cont of L') | |
| A reaction: Evolution never features in Lewis's metaphysics. I would have thought we were very much built to focus on natural properties. This sounds odd, and gives no help in distinguishing natural properties from all our other daft contents. |
| 15460 | All perfectly natural properties are intrinsic [Lewis, by Lewis] |
| Full Idea: Lewis proposed that all perfectly natural properties are intrinsic. | |
| From: report of David Lewis (New work for a theory of universals [1983], p.355-7) by David Lewis - Defining 'Intrinsic' (with Rae Langton) IX | |
| A reaction: Depends what you mean by 'natural', 'property' and 'intrinsic'! Presumably there are natural extrinsic facts, in naturally necessary relationships. If all natural properties are powers, they would have to be intrinsic. Extrinsics would be derivative. |
| 15726 | Natural properties fix resemblance and powers, and are picked out by universals [Lewis] |
| Full Idea: Perhaps we could call a property 'perfectly' natural if its members are all and only those things that share some one universal, ...where the natural properties would be the ones whose sharing makes for resemblance, and the ones relevant to causal powers. | |
| From: David Lewis (New work for a theory of universals [1983], 'Un and Prop') | |
| A reaction: This is Lewis fishing for an account of properties that does a bit better than the mere recourse to set theory (which he intuitively favours) seems to do. He remains neutral about the ontological status of a universal (though he prefers nominalism). |
| 14996 | Natural properties give similarity, joint carving, intrinsicness, specificity, homogeneity... [Lewis] |
| Full Idea: Sharing of [perfectly natural properties] makes for qualitative similarity, they carve at the joints, they are intrinsic, they are highly specific, the sets of their instances are ipso facto not highly miscellaneous. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: All this sounds like just what I want, but when I read Lewis he seems to be arriving at these natural properties by the wrong route. Too much Hume, too much extensionalism. |
| 15744 | We can't define natural properties by resemblance, if they are used to explain resemblance [Lewis] |
| Full Idea: Shall we say that natural properties are the ones whose instances are united by resemblance? - Not if we are going to say that resemblance is the sharing of natural properties. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: The target of this appears to be the proposal of Quinton. By now I have totally given up on so-called 'natural' properties. Lewis says the circularity (also in Idea 15743) is a reason to treat 'natural' here as primitive (though he rejects that). |
| 15743 | Defining natural properties by means of laws of nature is potentially circular [Lewis] |
| Full Idea: Shall we say that natural properties are the ones that figure in laws of nature? - Not if we are going to use naturalness of properties when we draw the line between laws of nature and accidental regularities. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: Personally I wouldn't dream of defining anything by saying that it figured in laws of nature. The laws, if there be such (see Mumford) are built up from more fundamental components, such as (perhaps) properties. |
| 15740 | I don't take 'natural' properties to be fixed by the nature of one possible world [Lewis] |
| Full Idea: Some people suppose my natural properties are distinguished by nature, and hence natural in one world and not another. I intend properties to be natural or unnatural simpliciter, not relative to one or another world. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5 n44) | |
| A reaction: This is an important warning for the likes of me. I've have begun to doubt the utility of the term 'natural' property, and this reinforces my view. |
| 16262 | Sparse properties rest either on universals, or on tropes, or on primitive naturalness [Lewis, by Maudlin] |
| Full Idea: Lewis surveys three accounts of sparse properties: a set of objects instantiating a single universal; a set of objects having as parts duplicates of some trope; and a set distinguished by a further unanalyzable, primitive characteristic of naturalness. | |
| From: report of David Lewis (On the Plurality of Worlds [1986], p.60-) by Tim Maudlin - The Metaphysics within Physics | |
| A reaction: The very idea of suggesting that a property is some set of objects strikes me as bizarre. I present you with a table full of objects and say that is the complete set of some property. You then have to study the objects to find out what the property is. |
| 15451 | I assume there could be natural properties that are not instantiated in our world [Lewis] |
| Full Idea: It is possible, I take it, that there might be simple natural properties different from any that instantiated within our world. | |
| From: David Lewis (Against Structural Universals [1986], 'Uninstantiated') | |
| A reaction: Interesting. Fine for Lewis, of course, for whom possibilities seem (to me) to be just logical possibilities. Even a scientific essentialist, though, must allow that different stuff might exist, which might have different intrinsic properties. |
| 7031 | Lewis says properties are sets of actual and possible objects [Lewis, by Heil] |
| Full Idea: David Lewis has produced an important theory of properties as sets of actual and possible objects. | |
| From: report of David Lewis (New work for a theory of universals [1983]) by John Heil - From an Ontological Point of View §12.2 | |
| A reaction: The notion that a property is an 'object' sounds wrong, as it is too passive. It also seems to allow for the possibility of uninstantiated properties existing, where properties are presumably always 'of' something. |
| 8572 | Any class of things is a property, no matter how whimsical or irrelevant [Lewis] |
| Full Idea: Any class of things, be it ever so gerrymandered and miscellaneous and indescribable in thought and language, and be it ever so superfluous in characterizing the world, is nevertheless a property. | |
| From: David Lewis (New work for a theory of universals [1983], 'Un and Prop') | |
| A reaction: I much prefer, at the very least, the sparse approach of Armstrong, and in fact would vote for Shoemaker's highly physical view. Lewis proceeds after this to try to pick out the properties that really matter. |
| 15464 | The distinction between dispositional and 'categorical' properties leads to confusion [Lewis] |
| Full Idea: To avoid the danger of claiming that dispositions are their own categorical bases, we do better to eschew the alleged distinction between dispositional and 'categorical' properties altogether. | |
| From: David Lewis (Finkish dispositions [1997], II) | |
| A reaction: Since I have been unable to form any intuitive notion of what a 'categorical' property is, I like this, though not necessarily for his reason. |
| 18433 | There are far more properties than any brain could ever encodify [Lewis] |
| Full Idea: There are so many properties that those specifiable in English, or in the brain's language of synaptic interconnections and neural spikes, could only be an infinitesimal minority. | |
| From: David Lewis (New work for a theory of universals [1983], 'Un and Prop') | |
| A reaction: Thus there are innumerable properties that must lack predicates. But there are also innumerable predicates that correspond to no real properties. I conclude that properties and predicates have very little in common. Job done. |
| 8604 | We need properties as semantic values for linguistic expressions [Lewis] |
| Full Idea: We need properties, sometimes natural and sometimes not, to provide an adequate supply of semantic values for linguistic expressions. | |
| From: David Lewis (New work for a theory of universals [1983], 'Un and Prop') | |
| A reaction: A characteristically twentieth century approach, which I find puzzling. We don't need a Loch Ness Monster in order to use the term 'Loch Ness Monster'. Lewis appears to have been a pupil of Quine... He was not, though, a Predicate Nominalist. |
| 15739 | There is the property of belonging to a set, so abundant properties are as numerous as the sets [Lewis] |
| Full Idea: The abundant properties far outrun the predicates of any language we could possibly possess. ...Properties are as abundant as the sets, because for any set whatever, there is the property of belonging to that set. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: The idea of calling such things 'properties' strikes me as preposterous, but it is interesting that we confront truths which outrun our predicates. We can't have all of these predicates together, but there is no impediment to any one of them. |
| 15563 | Properties are very abundant (unlike universals), and are used for semantics and higher-order variables [Lewis] |
| Full Idea: Properties are abundant, numbering at least beth-3 for properties of individuals alone; they are suited to serve as semantic values of arbitrarily complex predicates and gerunds, and higher-order variables. (If there are universals, they are sparse). | |
| From: David Lewis (Events [1986], II n2) | |
| A reaction: To me this is an outrageous hijacking of the notion of property which is needed for explaining the natural world. He seems to be talking about predicates. He wants to leave me with his silly universals - well I don't want them, thank you. |
| 10723 | A property is the set of its actual and possible instances [Lewis, by Oliver] |
| Full Idea: Lewis proposes that a property is the set of its actual and possible instances. | |
| From: report of David Lewis (On the Plurality of Worlds [1986], 1.5) by Alex Oliver - The Metaphysics of Properties 10 | |
| A reaction: I just can't make sense of any proposal that a property is a set. Things fall into natural sets because they have properties. Only a philosopher would believe such a weird proposal as this one. Triangular and trilateral? |
| 14499 | Properties are classes of possible and actual concrete particulars [Lewis, by Koslicki] |
| Full Idea: Lewis has a preference for a nominalist conception of properties as classes of possible and actual concrete particulars. | |
| From: report of David Lewis (New work for a theory of universals [1983]) by Kathrin Koslicki - The Structure of Objects II.3 | |
| A reaction: I'm sympathetic to nominalism, but still can't swallow the idea that a property like redness is nothing more than a collection of particulars, the red things. This class will include all sorts of non-red features. |
| 4038 | Properties are sets of their possible instances (which separates 'renate' from 'cordate') [Lewis, by Mellor/Oliver] |
| Full Idea: Lewis agrees that properties cannot be sets of their actual instances, but claims they can be sets of their possible instances. This would distinguish coextensive properties like being cordate and renate, since they might be separated. | |
| From: report of David Lewis (Modal Realism at Work: Properties [1986]) by DH Mellor / A Oliver - Introduction to 'Properties' §10 | |
| A reaction: Sounds wrong. Two properties could be obviously different even if they could never be separated. In this world a creature might briefly survive without kidneys. |
| 15399 | The property of being F is identical with the set of objects, in all possible worlds, which are F [Lewis, by Cameron] |
| Full Idea: Lewis thought that the property of being F was identical with the set of objects, in all possible worlds, which are F. | |
| From: report of David Lewis (On the Plurality of Worlds [1986], §1.5) by Ross P. Cameron - Intrinsic and Extrinsic Properties | |
| A reaction: I can't make head or tail of a theory which says that a property is a set of objects. I'll show you a room full of objects and tell you they are a property. How are you going to work out what the property is? 'Being F' is a predicate, not a property! |
| 15732 | Properties don't seem to be sets, because different properties can have the same set [Lewis] |
| Full Idea: The usual objection to taking properties as sets is that different properties may happen to be coextensive. Creatures with hearts are creatures with kidneys. Talking donkeys are flying pigs (since there are none). Yet the properties differ. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: This is the difficulty which Lewis proposes to solve by defining properties across possible situations as well as actual ones, so that the properties can come apart. Nice move. |
| 15733 | Accidentally coextensive properties come apart when we include their possible instances [Lewis] |
| Full Idea: In modal realism, 'accidentally coextensive' properties are not coextensive. They only appear so when we ignore their other-worldly instances. If we consider all instances, then it never can happen that two properties are coextensive but might have been. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: It is not clear why this 'can never happen'. Maybe even God can't make a hearted creature without kidneys. Lewis is aware of this question. |
| 15734 | If a property is relative, such as being a father or son, then set membership seems relative too [Lewis] |
| Full Idea: A property that is instantiated in a relative way (such as being a father or a son) could not be the set of its instances? Is the thing to be included in the set or not? | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: He says philosophers contrive ways to define properties as functions, but he prefers to call such properties 'relations', and define them that way. It never even occurred to me that 'being a son' was one of my properties, but what do I know? |
| 15516 | A property is any class of possibilia [Lewis] |
| Full Idea: A property is any class of possibilia. | |
| From: David Lewis (Parts of Classes [1991], 2.7) |
| 9655 | Trilateral and triangular seem to be coextensive sets in all possible worlds [Lewis] |
| Full Idea: We can't take a property as sets of this-worldly instances, because two properties may be coextensive. Some say it is just as bad in all possible worlds, if the property is necessary, as when all triangles are trilateral, which seem different. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: [compressed] Renate/cordate is the standard example of the first problem. Lewis seems to equivocate over exactly what is meant by a property. I take the example to be a powerful objection to treating properties as sets. |
| 16290 | I believe in properties, which are sets of possible individuals [Lewis] |
| Full Idea: I believe in properties. That is, I have my candidates for entities to play the role and deserve the name. My principal candidates are sets of possible individuals. | |
| From: David Lewis (On the Plurality of Worlds [1986], 3.4) | |
| A reaction: I am bewildered by any claim that a property is a 'set'. The property of being a teaspoon is just a large pile of teaspoons (one pile in each possible world)? This is the tyranny of first-order logic in philosophy. Are sets more real than properties? |
| 9653 | It would be easiest to take a property as the set of its instances [Lewis] |
| Full Idea: The simplest plan for properties is to take a property just as the set of all its instances. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: I find this a weird and counterintuitive proposal. I suppose if you think maths has been reduced to set theory, you might want to reduce everything else, and then we can all go home. I thought things were in sets because of their properties. |
| 9657 | You must accept primitive similarity to like tropes, but tropes give a good account of it [Lewis] |
| Full Idea: If you will not countenance primitive similarity in any form, then trope theory is not for you. But if you will, then duplication of tropes is an especially satisfactory form of primitive similarity to take. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: This presents the question about tropes in a beautifully simple form. Perfect similarities seem fine, but partial similarities (red and pink things) are hard, and abstract reference (pinkness and redness) is even harder. |
| 15433 | Tropes are particular properties, which cannot recur, but can be exact duplicates [Lewis] |
| Full Idea: Tropes are supposed to be particularized properties: nonspatiotemporal parts of their instances which cannot occur repeatedly, but can be exact duplicates. | |
| From: David Lewis (Against Structural Universals [1986], 'Intro') | |
| A reaction: Russell's objection is that 'duplication' appears to be a non-trope universal. The account seems wrong for very close resemblance, which is accepted by everyone as being the same (e.g. in colour, for football shirts). |
| 15750 | Tropes need a similarity primitive, so they cannot be used to explain similarity [Lewis] |
| Full Idea: Trope theory cannot analyse similarity, because duplication of tropes is itself a primitive relation of similarity. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: A reasonable reply to this one, I think, is that no one can explain or analyse similarity. To say that the same universal (or bunch of graded universals) is instantiated explains nothing. Maybe type-identity must be primitive in any theory? |
| 15749 | Trope theory (unlike universals) needs a primitive notion of being duplicates [Lewis] |
| Full Idea: Trope theory has the drawback that we need the primitive notion of duplicate tropes, whereas with universals we just say that it is one and the same universal through some charged particles. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: The normal term for this primitive is 'perfect resemblance', though that seems to make close resemblance a bit complicated and puzzling. I'm not sure if I understand resemblance as a feature of the world, rather than of our minds. |
| 15748 | Trope theory needs a primitive notion for what unites some tropes [Lewis] |
| Full Idea: Trope theory needs a primitive notion - 'instantion' in yet another sense - to say how the tropes that comprise a particle are united. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: Any theory which says that objects are just 'bundles' of tropes is asking for trouble. But if you say (with Lowe and others) that tropes are 'modes' of existing entities, you still have to give an account of the entity. |