121 ideas
| 19648 | Since Kant we think we can only access 'correlations' between thinking and being [Meillassoux] |
| Full Idea: The central notion of philosophy since Kant is 'correlation' - that we only ever have access to the correlation between thinking and being, and never to either term considered apart from the other. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 1) | |
| A reaction: Meillassoux's charge is that philosophy has thereby completely failed to grasp the scientific revolution, which has used mathematics to make objectivity possible. Quine and Putnam would be good examples of what he has in mind. |
| 19674 | The Copernican Revolution decentres the Earth, but also decentres thinking from reality [Meillassoux] |
| Full Idea: The Copernican Revolution is not so much the decentring of observers in the solar system, but (by the mathematizing of nature) the decentring of thought relative to the world within the process of knowledge. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 5) | |
| A reaction: In other words, I take it, the Copernican Revolution was the discovery of objectivity. That is a very nice addition to my History of Ideas collection. |
| 19657 | In Kant the thing-in-itself is unknowable, but for us it has become unthinkable [Meillassoux] |
| Full Idea: The major shift that has occurred in the conception of thought from Kant's time to ours is from the unknowability of the thing-in-itself to its unthinkability. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 2) | |
| A reaction: Meillassoux is making the case that philosophy is alienating us more and more from the triumphant realism of the scientific revolution. He says thinking has split from being. He's right. Modern American pragmatists are the worst (not Peirce!). |
| 16281 | Honesty requires philosophical theories we can commit to with our ordinary commonsense [Lewis] |
| Full Idea: The maxim of honesty: never put forward a philosophical theory that you yourself cannot believe in your least philosophical and most commonsensical moments. | |
| From: David Lewis (On the Plurality of Worlds [1986], 2.8) | |
| A reaction: I take it as important that this test is according to the philosopher's commonsense, and not according to some populist idea. This would allow, for example, for commonsense to be sensitive to scientific knowledge, or awareness of the logic. |
| 16288 | Analysis reduces primitives and makes understanding explicit (without adding new knowledge) [Lewis] |
| Full Idea: The object of analysis is to reduce our burden of primitive notions, and to make tacit understanding explicit - not to bootstrap ourselves into understanding what we didn't understand at all beforehand. | |
| From: David Lewis (On the Plurality of Worlds [1986], 3.2) | |
| A reaction: I am particularly keen on the idea of 'making tacit understanding explicit'. I connect this with faith in intuition, and with the coherence view of justification. |
| 19675 | Since Kant, philosophers have claimed to understand science better than scientists do [Meillassoux] |
| Full Idea: Ever since Kant, to think science as a philosopher has been to claim that science harbours a meaning other than the one delivered by science itself. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 5) | |
| A reaction: The point is that science discovered objectivity (via the mathematising of nature), and Kant utterly rejected objectivity, by enmeshing the human mind in every possible scientific claim. This makes Meillassoux and I very cross. |
| 19649 | Since Kant, objectivity is defined not by the object, but by the statement's potential universality [Meillassoux] |
| Full Idea: Since Kant, objectivity is no longer defined with reference to the object in itself, but rather with reference to the possible universality of an objective statement. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 1) | |
| A reaction: Meillassoux disapproves of this, as a betrayal by philosophers of the scientific revolution, which gave us true objectivity (e.g. about how the world was before humanity). |
| 19666 | If we insist on Sufficient Reason the world will always be a mystery to us [Meillassoux] |
| Full Idea: So long as we continue to believe that there is a reason why things are the way they are rather than some other way, we will construe this world is a mystery, since no such reason will every be vouchsafed to us. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 4) | |
| A reaction: Giving up sufficient reason sounds like a rather drastic response to this. Put it like this: Will we ever be able to explain absolutely everything? No. So will the world always be a little mysterious to us? Yes, obviously. Is that a problem? No! |
| 19656 | Non-contradiction is unjustified, so it only reveals a fact about thinking, not about reality? [Meillassoux] |
| Full Idea: The principle of non-contradiction itself is without reason, and consequently it can only be the norm for what is thinkable by us, rather than for what is possible in the absolute sense. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 2) | |
| A reaction: This is not Meillassoux's view, but describes the modern heresy of 'correlationism', which ties all assessments of how reality is to our capacity to think about it. Personally I take logical non-contradiction to derive from non-contradiction in nature. |
| 9651 | Verisimilitude might be explained as being close to the possible world where the truth is exact [Lewis] |
| Full Idea: We might explain the closeness to the truth (or 'verisimilitude') in terms of closeness of possible worlds. A theory is close to the truth to the extent that our world resembles some world where that theory is exactly true. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.3) | |
| A reaction: [Lewis cites Risto Hilpinen for this thought] I am always puzzled why Lewis and co. talk of whole worlds in their accounts. If I am close to the truth about cooking a good omelette, what has the rest of the world got to do with it? |
| 19663 | We can allow contradictions in thought, but not inconsistency [Meillassoux] |
| Full Idea: For contemporary logicians, it is not non-contradiction that provides the criterion for what is thinkable, but rather inconsistency. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 3) | |
| A reaction: The point is that para-consistent logic might permit isolated contradictions (as true) within a system, but it is only contradiction across the system (inconsistencies) which make the system untenable. |
| 19664 | Paraconsistent logics are to prevent computers crashing when data conflicts [Meillassoux] |
| Full Idea: Paraconsistent logics were only developed in order to prevent computers, such as expert medical systems, from deducing anything whatsoever from contradictory data, because of the principle of 'ex falso quodlibet'. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 3) |
| 19665 | Paraconsistent logic is about statements, not about contradictions in reality [Meillassoux] |
| Full Idea: Paraconsistent logics are only ever dealing with contradictions inherent in statements about the world, never with the real contradictions in the world. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 3) | |
| A reaction: Thank goodness for that! I can accept that someone in a doorway is both in the room and not in the room, but not that they are existing in a real state of contradiction. I fear that a few daft people embrace the logic as confirming contradictory reality. |
| 15731 | Quantification sometimes commits to 'sets', but sometimes just to pluralities (or 'classes') [Lewis] |
| Full Idea: I consider some apparent quantification over sets or classes of whatnots to carry genuine ontological commitment to 'sets' of them, but sometimes it is innocent plural quantification committed only to whatnots, for which I use 'class'. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5 n37) | |
| A reaction: How do you tell whether you are committed to a set or not? Can I claim an innocent plurality each time, while you accuse me of a guilty set? Can I firmly commit to a set, to be told that I can never manage more than a plurality? |
| 19677 | What is mathematically conceivable is absolutely possible [Meillassoux] |
| Full Idea: We must establish the thesis that what is mathematically conceivable is absolutely possible. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 5) | |
| A reaction: The truth of this thesis would permanently establish mathematics as the only possible language of science. Personally I have no idea how you could prove or assess such a thesis. It is a lovely speculation, though. 'The structure of the possible' (p,127) |
| 19659 | The absolute is the impossibility of there being a necessary existent [Meillassoux] |
| Full Idea: We maintain that it is absolutely necessary that every entity might not exist. ...The absolute is the absolute impossibility of a necessary being. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 3) | |
| A reaction: This is the main thesis of his book. The usual candidates for necessary existence are God, and mathematical objects. I am inclined to agree with Meillassoux. |
| 10470 | There are only two kinds: sets, and possibilia (actual and possible particulars) [Lewis, by Oliver] |
| Full Idea: Lewis's multi-purpose ontology seems to have only two kinds: sets and possibilia (actual and possible particulars). | |
| From: report of David Lewis (On the Plurality of Worlds [1986]) by Alex Oliver - The Metaphysics of Properties 3 | |
| A reaction: This is awfully like the ontology of his teacher Quine, but with the wicked addition of modal properties. It is no wonder that Lewis was a bit vague about the concrete boundary, as both of his kinds seem to be abstract. His Achilles' Heel? |
| 19662 | It is necessarily contingent that there is one thing rather than another - so something must exist [Meillassoux] |
| Full Idea: It is necessary that there be something rather than nothing because it is necessarily contingent that there is something rather than something else. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 3) | |
| A reaction: The great charm of metaphysics is the array of serious answers to the question of why there is something rather than nothing. You'll need to read Meillassoux's book to understand this one. |
| 19654 | We must give up the modern criterion of existence, which is a correlation between thought and being [Meillassoux] |
| Full Idea: It is incumbent upon us to break with the ontological requisite of the moderns, according to which 'to be is to be a correlate'. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 2) | |
| A reaction: He blames Kant for this pernicious idea, which has driven philosophy away from realist science, when it should be supporting and joining it. As a realist I agree, and find Meillassoux very illuminating on the subject. |
| 9650 | Supervenience concerns whether things could differ, so it is a modal notion [Lewis] |
| Full Idea: The idea of supervenience is when there could be no difference of one sort without difference of another sort. ..Clearly this 'could' indicates modality, and without modality we have nothing of interest. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.2) | |
| A reaction: This might explain why philosophers are going to be more at home with the concept than neuroscientists would be. |
| 8909 | Abstractions may well be verbal fictions, in which we ignore some features of an object [Lewis] |
| Full Idea: The inevitable hypothesis is that abstractions are verbal fictions. We say we are speaking about abstractions when we are speaking abstractly about the original thing. We are ignoring some features, not introducing a new thing lacking those features. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.7) | |
| A reaction: Thus Lewis ends up pretty close to Locke and the traditional view. This makes abstraction not a feat of platonic perception, in which magical non-material objects are spotted, but a feat of counterfactual imagination. |
| 9057 | Vagueness is semantic indecision: we haven't settled quite what our words are meant to express [Lewis] |
| Full Idea: I regard vagueness as semantic indecision: where we speak vaguely, we have not troubled to settle which of some range of precise meanings our words are meant to express. | |
| From: David Lewis (On the Plurality of Worlds [1986], 4.4 n32) | |
| A reaction: But that seems to leave the problem of how you are going to decide the boundaries of 'heap' or 'bald', if we all agree to become more precise. In law precise boundaries are often drawn a bit arbitrarily, simply because a boundary is needed. |
| 9671 | Whether or not France is hexagonal depends on your standards of precision [Lewis] |
| Full Idea: Say that France is hexagonal, and you thereby set the standards of precision low, and you speak the truth; say that France is not hexagonal (preferably on some other occasion) and you set the standards high, and again you speak the truth. | |
| From: David Lewis (On the Plurality of Worlds [1986], 4.5) | |
| A reaction: This is very persuasive. It fits with my views on justification, which are to do with how high I (or more often 'we') decide to set the standards, thereby defining knowledge for that occasion. Hm. Has Lewis cracked vagueness? [P.S. NO!] |
| 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. |
| 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. |
| 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). |
| 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? |
| 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. |
| 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. |
| 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? |
| 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? |
| 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. |
| 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. |
| 15745 | Universals recur, are multiply located, wholly present, make things overlap, and are held in common [Lewis] |
| Full Idea: One and the same universal recurs; it is multiply located; it is wholly present in both instances, a shared common part whereby the two instances overlap. Being alike by sharing a universal is 'having something in common' in an absolutely literal sense. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: A helpful spelling out of the commitment involved (in Armstrong and others) in belief in universals. To me this is a convenient list of reasons why the whole proposal is nonsense. Why does Lewis take them seriously? |
| 15746 | If particles were just made of universals, similar particles would be the same particle [Lewis] |
| Full Idea: We cannot say that a particle is composed entirely of its several universals, because then another particle exactly like it would have the very same universals, and yet the two particles would not be the same. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: This is an argument either (implausibly) for haecceities or characterless substrata, or else for tropes (which are all separate, unlike universals). Particles as bundles of universals is not a theory I take seriously. |
| 15747 | Universals aren't parts of things, because that relationship is transitive, and universals need not be [Lewis] |
| Full Idea: It cannot be said that a universal is instantiated by anything that has it as a part, since the relation of part to whole is transitive. If charge is part of a particle, which is part of an atom, then charge is part of the atom, but an atom isn't charged. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: Given the total mystery involved in 'instantiation', it wouldn't surprise me if someone appealed to the part-whole relation, but all moves to explain instantiation are desperate. Make it a primitive, if you must, then tiptoe away. |
| 9667 | Mereological composition is unrestricted: any class of things has a mereological sum [Lewis] |
| Full Idea: I claim that mereological composition is unrestricted: any old class of things has a mereological sum. Whenever there are some things, even out of different possible worlds, there is something composed of just those things. | |
| From: David Lewis (On the Plurality of Worlds [1986], 4.3) | |
| A reaction: To say the least, a rather unusual usage for the English word 'thing'. I presume that Lewis is in the grip of a slippery slope problem - that there is no way to define the borderline between things and non-things. Presumably 'class' is unrestricted too. |
| 13268 | There are no restrictions on composition, because they would be vague, and composition can't be vague [Lewis, by Sider] |
| Full Idea: Lewis says that if not every class has a fusion then there must be a restriction on composition. The only plausible restrictions would be vague ones, which is impossible, because then whether composition occurs would be vague. So every class has a fusion. | |
| From: report of David Lewis (On the Plurality of Worlds [1986], p.212-3) by Theodore Sider - Four Dimensionalism 9.1 | |
| A reaction: This is Lewis's key argument in favour of unrestricted composition, his Vagueness Argument. Why can't composition be vague? If you gradually reassemble a broken mirror, at what point does the mirror acquire its unity? |
| 13793 | An essential property is one possessed by all counterparts [Lewis, by Elder] |
| Full Idea: For Lewis, if a property possessed by a given individual or kind is missing in some of the contextually relevant counterparts, that property is accidental to the individual or kind; if it is possessed by all of them, that property is essential. | |
| From: report of David Lewis (On the Plurality of Worlds [1986], 248-263) by Crawford L. Elder - Real Natures and Familiar Objects 1.4 | |
| A reaction: This is a sophisticated version of the idea that essential properties are just necessary properties. It might make sense with a very sparse view of properties (mainly causal ones), but I think of essences as quite different from necessities. |
| 9663 | A thing 'perdures' if it has separate temporal parts, and 'endures' if it is wholly present at different times [Lewis] |
| Full Idea: Something 'perdures' iff it persists by having different temporal parts, or stages, at different times, though no one part of it is wholly present at more than one time; whereas it 'endures' iff it persists by being wholly present at more than one time. | |
| From: David Lewis (On the Plurality of Worlds [1986], 4.2) | |
| A reaction: Only a philosopher would come up with a concept like perdurance. I'm thinking about this one, and will get back to you in a later-numbered idea... He compares perdurance to the way a road persists through space. |
| 14737 | Properties cannot be relations to times, if there are temporary properties which are intrinsic [Lewis, by Sider] |
| Full Idea: The problem of 'temporary intrinsics' is that in one model we think of properties as relations to times (I am 'bent' relative to now), but change sometime involves intrinsic properties. I am just plain bent, not bent with respect to something else. | |
| From: report of David Lewis (On the Plurality of Worlds [1986], p.202-4) by Theodore Sider - Four Dimensionalism | |
| A reaction: [I've compressed Sider's summary] The question of whether intrinsic properties endure over time runs in parallel with the question of whether objects endure over time, and the two issues cannot be separated. |
| 9664 | Endurance is the wrong account, because things change intrinsic properties like shape [Lewis] |
| Full Idea: The principal and decisive objection to endurance, as an account of the persistence of ordinary things, is the problem of temporary intrinsics. Persisting things change their intrinsic properties, such as their shape. My own shape keeps changing. | |
| From: David Lewis (On the Plurality of Worlds [1986], 4.2) | |
| A reaction: Presumably if something was going to endure through time it would need a shape. If it has no particular shape, it lacks identity? Lewis discusses the problem at length. Why is a precise shape essential to anything? |
| 9665 | There are three responses to the problem that intrinsic shapes do not endure [Lewis] |
| Full Idea: The problem for the endurance view of temporary intrinsic properties like shape is met be either saying shape is a disguised relational property, or only present properties are intrinsic, or the shapes belong to different things (perdurance). | |
| From: David Lewis (On the Plurality of Worlds [1986], 4.2) | |
| A reaction: [compressed] It is certainly implausible to deny that shape is a feature of all physical objects. Or it appears to be. Shapes are hard to pin down at the quantum level. How do you sharply divide moments for the perdurance view? ... |
| 19280 | I can ask questions which create a context in which origin ceases to be essential [Lewis] |
| Full Idea: If I ask how things would be if Saul Kripke had come from no sperm and egg, but was brought by a stork, that makes sense. I create a context that makes my question make sense, which is a context that makes origin not to be essential. | |
| From: David Lewis (On the Plurality of Worlds [1986], 4.5) | |
| A reaction: I'm not clear why delivery by a stork doesn't just count as a different origin, and hence it turns out to be essential to Kripke. If Kripke were a necessary being (and he's a good candidate), then he would have no origin. |
| 15968 | Identity is simple - absolutely everything is self-identical, and nothing is identical to another thing [Lewis] |
| Full Idea: Identity is utterly simple and unproblematic. Everything is identical to itself; nothing is ever identical to anything except itself. There is never any problem about what makes something identical to itself; nothing can ever fail to be. | |
| From: David Lewis (On the Plurality of Worlds [1986], 4.1) | |
| A reaction: I have great problems with expressing this concept as a thing being 'identical to itself'. I will always say that it 'has an identity'. But then it is problematical, because what constitutes an identity? When do dispersing clouds lose it? |
| 15969 | Two things can never be identical, so there is no problem [Lewis] |
| Full Idea: There is never any problem about what makes two things identical; two things can never be identical. | |
| From: David Lewis (On the Plurality of Worlds [1986], 4.1) | |
| A reaction: This expresses Lewis's preference for usage of the word 'identity', rather than a simple solution. It pays no attention to type-identity, which is an obvious phenomenon. In some sense, it is just obvious that two electrons are 'identical'. |
| 19660 | Possible non-being which must be realised is 'precariousness'; absolute contingency might never not-be [Meillassoux] |
| Full Idea: My term 'precariousness' designates a possibility of not-being which must eventually be realised. By contrast, absolute contingency designates a pure possibility; one which may never be realised. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 3) | |
| A reaction: I thoroughly approve of this distinction, because I have often enountered the assumption that all contingency is precariousness, and I have never seen why that should be so. In Aquinas's Third Way, for example. The 6 on a die may never come up. |
| 19671 | The idea of chance relies on unalterable physical laws [Meillassoux] |
| Full Idea: The very notion of chance is only conceivable on condition that there are unalterable physical laws. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 4) | |
| A reaction: Laws might be contingent, even though they never alter. Chance in horse racing relies on the stability of whole institution of horse racing. |
| 9660 | The impossible can be imagined as long as it is a bit vague [Lewis] |
| Full Idea: Imaginability is a poor criterion of possibility. We can imagine the impossible provided we do not imagine it in perfect detail and all the time. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.8) | |
| A reaction: In general I agree, but Williamson nicely opposes this view. The fact is that we derive most of our understanding of what is possible from imagination. We just have to realise that we can get it wrong, and so must attend to detail. |
| 9669 | There are no free-floating possibilia; they have mates in a world, giving them extrinsic properties [Lewis] |
| Full Idea: There are no free-floating possibilia. Every possibility is part of a world - exactly one world - and thus comes surrounded by worldmates, and fully equipped with extrinsic properties in virtue of its relations to them. | |
| From: David Lewis (On the Plurality of Worlds [1986], 4.4) | |
| A reaction: This is a key claim in the possible worlds understanding of modality, contrary to the more common sense and normal language claim that a possibility is an isolated thing. |
| 16133 | Possible worlds can contain contradictions if such worlds are seen as fictions [Lewis] |
| Full Idea: If worlds were like stories or story-tellers, there would indeed be room for worlds according to which contradictions are true. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.2 n3) | |
| A reaction: Most existing fictions contain tiny contradictions, but we might ask whether that thereby disqualifies them from depicting genuinely 'possible' worlds. |
| 16132 | On mountains or in worlds, reporting contradictions is contradictory, so no such truths can be reported [Lewis] |
| Full Idea: To tell the alleged truth about contradictory things that happen on a mountain is just contradicting yourself, but you can't tell the truth by contradicting yourself. There is no mountain where contradictions are true, and impossible worlds are no better. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.2 n3) | |
| A reaction: [compressed] He says this works for any 'restricted' domain like a mountain or a real world, but that it wouldn't apply in an unrestricted fictional world. |
| 16283 | For me, all worlds are equal, with each being actual relative to itself [Lewis] |
| Full Idea: For me, all the worlds are on an equal footing in that each is actual relative to itself and none is actual relative to any other. | |
| From: David Lewis (On the Plurality of Worlds [1986], 3.1) | |
| A reaction: Lewis says the world we call 'actual' is simply a matter of how our indexicals refer. That sounds the wrong way round to me (as so often with Lewis). |
| 12255 | For Lewis there is no real possibility, since all possibilities are actual [Oderberg on Lewis] |
| Full Idea: Lewis-style modal realism eliminates all real possibility since on his account everything is actual relative to its own world. | |
| From: comment on David Lewis (On the Plurality of Worlds [1986]) by David S. Oderberg - Real Essentialism 6.2 | |
| A reaction: Since it is possible for me to be in New York and in Chicago, but not both at once, his possibilities have to be kept apart, even though they are actual. I expect my visit to Chicago to remain as only a possibility. |
| 9219 | Lewis posits possible worlds just as Quine says that physics needs numbers and sets [Lewis, by Sider] |
| Full Idea: Lewis's argument for possible worlds parallels Quine's for the existence of sets: our best overall empirical theory, mathematical physics, quantifies over real numbers, so we have reason to posit real numbers, or the sets to which they may be reduced. | |
| From: report of David Lewis (On the Plurality of Worlds [1986]) by Theodore Sider - Reductive Theories of Modality 3.6 | |
| A reaction: They both strike me as suspect. Indeed, the extreme implausibility of Lewis's conclusion throws doubt on Quine's original strategy. I'm happy to work with sets and possible worlds, and only worry about ontological commitment at a later stage. |
| 15022 | If possible worlds really exist, then they are part of actuality [Sider on Lewis] |
| Full Idea: The familiar complaint against Lewis is that if his worlds existed, they'd be part of actuality. | |
| From: comment on David Lewis (On the Plurality of Worlds [1986]) by Theodore Sider - Writing the Book of the World 11.5 | |
| A reaction: Sider presents that as rather superficial, but it sounds a pretty good objection to me. Lewis would note that only our world has the indexical features which he says pick out actuality. Real possible worlds might lack indexical features? |
| 10469 | A world is a maximal mereological sum of spatiotemporally interrelated things [Lewis] |
| Full Idea: A world is a maximal mereological sum of spatiotemporally interrelated things. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.6) | |
| A reaction: (I wonder what Lewis's account of space was?) A mereological sum is "the least inclusive thing that includes all the parts" (p.69). It is maximal when all 'worldmates' are parts. But then 'worldmates' are defined as parts, so it threatens circularity. |
| 16441 | Lewis rejects actualism because he identifies properties with sets [Lewis, by Stalnaker] |
| Full Idea: It is the identification of properties with sets that rules out, for Lewis, an actualist account of possible worlds. | |
| From: report of David Lewis (On the Plurality of Worlds [1986]) by Robert C. Stalnaker - Mere Possibilities 1.1 | |
| A reaction: I suppose the sets which are the properties have to include all the possible red things as well as the actual one. This escapes the renate/cordate problem. |
| 16282 | Ersatzers say we have one world, and abstract representations of how it might have been [Lewis] |
| Full Idea: The ersatzers say that instead of an incredible plurality of concrete worlds, we can have one world only, and countless abstract entities representing ways that this world might have been. | |
| From: David Lewis (On the Plurality of Worlds [1986], 3.1) | |
| A reaction: Put me down as an ersatzer. They seem to be the same as Actualists. Are worlds other possible worlds, or ways 'this world might have been'? Not the same. Does actuality constrain what is possible? (Barcan formula?) |
| 16284 | Ersatz worlds represent either through language, or by models, or magically [Lewis] |
| Full Idea: I distinguish three principal ways ersatz worlds represent: linguistic, in which they are like stories or theories; pictorial, like pictures or isomorphic scale models; or magical, in which it is just their nature to represent. | |
| From: David Lewis (On the Plurality of Worlds [1986], 3.1) | |
| A reaction: I think I incline to the 'model' view. The linguistic version means animals can't assess possibilities. I take modelling to be basic to what a mind is, and what a mind is for. |
| 16286 | Linguistic possible worlds need a complete supply of unique names for each thing [Lewis] |
| Full Idea: There are two difficulties with Carnap's taking possible worlds as linguistic. Everything must have a name, or our state-descriptions will be silent about nameless things, and nothing may have two names, or we may affirm and deny a predicate of one thing. | |
| From: David Lewis (On the Plurality of Worlds [1986], 3.2) | |
| A reaction: The idea of possible worlds as linguistic has no appeal for me, so this problem doesn't surprise or bother me, but it sounds fairly terminal for the project. |
| 16287 | Maximal consistency for a world seems a modal distinction, concerning what could be true together [Lewis] |
| Full Idea: An ersatz world must be maximally consistent (hence destroyed by an additional sentences), …but that is prima facie a modal distinction: a set of sentences is consistent iff those sentences, as interpreted, could all be true together. | |
| From: David Lewis (On the Plurality of Worlds [1986], 3.2) | |
| A reaction: This is indicative of Lewis's motivation for his project, which is to eliminate modal facts from the world. Only a vast multitude of non-modal concrete worlds can satisfy all the contraints. Cf many-worlds quantum mechanics for non-locality. |
| 9662 | Linguistic possible worlds have problems of inconsistencies, no indiscernibles, and vocabulary [Lewis] |
| Full Idea: Linguistic representations of possible worlds have three problems: some descriptions are inconsistent (which worlds cannot be); we cannot have indiscernible descriptions (though some worlds might be so); and descriptions are limited by vocabulary. | |
| From: David Lewis (On the Plurality of Worlds [1986], 3.2) | |
| A reaction: Lewis is wonderful at getting problems clearly on the table. I take the idea of possible worlds as linguistic entities to be a non-starter, because (as usual) animals do it too, when they think of possibilities, which even the dimmest ones must do. |
| 7690 | If sets exist, then defining worlds as proposition sets implies an odd distinction between existing and actual [Jacquette on Lewis] |
| Full Idea: If sets exist, then the conventional concept of a logically possible world as a proposition set requires a counterintuitive distinction between existence and actuality, between what exists and what is actual. | |
| From: comment on David Lewis (On the Plurality of Worlds [1986]) by Dale Jacquette - Ontology Ch.2 | |
| A reaction: This pinpoints the obvious difficulty that most people have with Lewis's claim that possible worlds exist. Russell's claim that universals 'subsist' (Idea 5409) is a similar attempt to have two different sorts of existence in your ontology. |
| 14404 | The counterpart relation is sortal-relative, so objects need not be a certain way [Lewis, by Merricks] |
| Full Idea: Lewis takes the counterpart relation to be sortal-relative, so he (no less than Quine) denies that objects, qua existing, are necessarily a certain way. | |
| From: report of David Lewis (On the Plurality of Worlds [1986]) by Trenton Merricks - Truth and Ontology 5.III n10 | |
| A reaction: Does this mean that there could be two different versions of the same possible world (certainly not!), or that worlds are entirely created by our concepts rather than by what is actually possible. |
| 5440 | A counterpart in a possible world is sufficiently similar, and more similar than anything else [Lewis, by Mautner] |
| Full Idea: 'Jack could have been taller' implies a different Jack in a different world, so Lewis defines a counterpart in a possible world as an individual sufficiently similar to Jack, and more similar to Jack than anything else in that world. | |
| From: report of David Lewis (On the Plurality of Worlds [1986]) by Thomas Mautner - Penguin Dictionary of Philosophy p.115 | |
| A reaction: If we say something like "I could have been twins" or "I could have been a genius" in another world, it would need an odd concept of my personal identity for it to remain identical in those counterfactual situations. Lewis has a point. |
| 5441 | Why should statements about what my 'counterpart' could have done interest me? [Mautner on Lewis] |
| Full Idea: If I only have counterparts in possible worlds who are not identical to me, statements about what I could have done will seem irrelevant to me, because they will be about someone else. | |
| From: comment on David Lewis (On the Plurality of Worlds [1986]) by Thomas Mautner - Penguin Dictionary of Philosophy p.115 | |
| A reaction: We might rephrase the statement as "I could have been the person who did x". Presumably my counterpart is not just any stranger, but someone I could have been. "I could have been a brick" - now that seems irrelevant to me! |
| 16291 | In counterpart theory 'Humphrey' doesn't name one being, but a mereological sum of many beings [Lewis] |
| Full Idea: For the counterpart theorist, the trick is to say that 'Humphrey' names not the Humphrey of our world, and not the Humphrey of another, but rather the trans-world individual who is the mereological sum of all those local Humphreys. | |
| From: David Lewis (On the Plurality of Worlds [1986], 4.1) | |
| A reaction: On Lewis's perdurantism Humphrey is a 'spacetime worm' across his lifetime. Now we are adding all the possible Humphreys to the sum. I'm losing track of Humphrey's shape. |
| 11903 | Extreme haecceitists could say I might have been a poached egg, but it is too remote to consider [Lewis, by Mackie,P] |
| Full Idea: Lewis's strategy for defending extreme haecceitism is that supposed impossibilities (that I might have been a poached egg) could be reconstrued as genuine possibilities that are so remote from reality that they are ignored. | |
| From: report of David Lewis (On the Plurality of Worlds [1986], 239-) by Penelope Mackie - How Things Might Have Been 9.3 | |
| A reaction: Not a promising route. Wiggins asks: if you think I could have been a poached egg, start by defining more precisely this 'I' to which we are referring. The definition will blatantly exclude any possibility of my poachedegghood. |
| 15129 | Haecceitism implies de re differences but qualitative identity [Lewis] |
| Full Idea: If two worlds differ in what they represent de re concerning some individual, but do not differ qualitatively in any way, I shall call that a haecceitist difference. Haecceitism, then, says there are at least some haecceitist differences between worlds. | |
| From: David Lewis (On the Plurality of Worlds [1986], 4.4) | |
| A reaction: Lewis bases this view on Kaplan. My brief summary of this is that 'identity may be hidden'. If all electrons are different, what distinguishes them? |
| 9670 | Extreme haecceitism says you might possibly be a poached egg [Lewis] |
| Full Idea: The most extreme version of haecceitism says that anything could possibly have any qualitative character; for instance, there is a world according to which you are a poached egg. | |
| From: David Lewis (On the Plurality of Worlds [1986], 4.4) | |
| A reaction: Presumably a plausible haecceitist view would have to be combined with essentialism, given that the possibility that I might be a poached egg is beyond my intuitive grasp. |
| 19651 | Unlike speculative idealism, transcendental idealism assumes the mind is embodied [Meillassoux] |
| Full Idea: What distinguishes transcendental idealism from speculative idealism is the fact that the former does not posit the existence of the transcendental subject apart from its bodily individuation. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 1) | |
| A reaction: These modern French philosophers explain things so much more clearly than the English! The 'speculative' version is seen in Berkeley. On p.17 he says transcendental idealism is 'civilised', and speculative idealism is 'uncouth'. |
| 19647 | The aspects of objects that can be mathematical allow it to have objective properties [Meillassoux] |
| Full Idea: All aspects of the object that can give rise to a mathematical thought rather than to a perception or a sensation can be meaningfully turned into the properties of the thing not only as it is with me, but also as it is without me. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 1) | |
| A reaction: This is Meillassoux's spin on the primary/secondary distinction, which he places at the heart of the scientific revolution. Cartesian dualism offers a separate space for the secondary qualities. He is appalled when philosophers reject the distinction. |
| 16279 | General causal theories of knowledge are refuted by mathematics [Lewis] |
| Full Idea: Causal accounts of knowledge are all very well in their place, but if they are put forward as general theories, then mathematics refutes them. | |
| From: David Lewis (On the Plurality of Worlds [1986], 2.4) | |
| A reaction: You might have some sort of notion of an abstraction from causation which mimicked it in the mathematics case. Lots of things seem to be 'forced' in mathematics. Call it 'ersatz causation'. Necessities are enforcers. |
| 12890 | That standards vary with context doesn't imply different truth-conditions for judgements [Conee] |
| Full Idea: The fact that different standards are routinely applied in making an evaluative judgement does not imply the correctness of semantic contextualism about the contents of judgements. ..We can't infer different truth conditions from differing standards. | |
| From: Earl Conee (Contextualism Contested [2005], p.51) | |
| A reaction: This is the basic objection to contextualism from the 'invariantist' camp, which says there are facts about good judgement and justification, despite contextual shifts. My sympathies are with the contextualists (on this one). |
| 12892 | Maybe there is only one context (the 'really and truly' one) for serious discussions of knowledge [Conee] |
| Full Idea: Maybe every issue about knowledge (Gettier problem, scientific knowledge, justification, scepticism) has been discussed solely in the single 'really and truly' context. | |
| From: Earl Conee (Contextualism Contested [2005], p.53) | |
| A reaction: This seems not to be true, if we contrast Descartes' desire for total certainty with Peirce's fallibilism. It seems to me that modern philosophy has deliberately relaxed the standard, in order to make some sort of knowledge possible. Cf. Idea 12894. |
| 19652 | How can we mathematically describe a world that lacks humans? [Meillassoux] |
| Full Idea: How is mathematical discourse able to describe a reality where humanity is absent? | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 1) | |
| A reaction: He is referring to the prehistoric world. He takes this to be a key question about the laws of nature. We extrapolate mathematically from the experienced world, relying on the stability of the laws. Must they be necessary to be stable? No, it seems. |
| 9661 | Induction is just reasonable methods of inferring the unobserved from the observed [Lewis] |
| Full Idea: I use the word 'induction' broadly, to cover all the methods we deem reasonable for forming beliefs about the unobserved parts of our world on the basis of experience with the observed parts. | |
| From: David Lewis (On the Plurality of Worlds [1986], 2.5) | |
| A reaction: Good. Attempts to be precise about it seem to be hopeless and invite paradoxes. Personally I just define it as 'learning from experience', because that makes what we do continuous with the behaviour of other sensible animals. |
| 19668 | Hume's question is whether experimental science will still be valid tomorrow [Meillassoux] |
| Full Idea: Hume's question can be formulated as follows: can we demonstrate that the experimental science which is possible today will still be possible tomorrow? | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 4) | |
| A reaction: Could there be deep universal changes going on in nature which science could never, even in principle, detect? |
| 9652 | To just expect unexamined emeralds to be grue would be totally unreasonable [Lewis] |
| Full Idea: Some beliefs are just unreasonable in a strong sense. Think of the man who, for no special reason, expects unexamined emeralds to be grue. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.4) | |
| A reaction: This is a nice converse way of seeing the point that 'grue' is such an totally artificial predicate. I still say that the most illuminating point is that grue is not a colour, so seeing a grue thing is no confirmation at all. |
| 9658 | An explanation tells us how an event was caused [Lewis] |
| Full Idea: An explanation, I think, is an account of etiology: it tells us something about how an event was caused. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: Will this cover mathematical explanations? Numbers would have to have causal powers. |
| 16280 | Often explanaton seeks fundamental laws, rather than causal histories [Lewis] |
| Full Idea: Sometimes the pursuit of explanation is more the pursuit of unified and general fundamental laws than of information about the causal histories of events. | |
| From: David Lewis (On the Plurality of Worlds [1986], 2.7) | |
| A reaction: It is hard to disagree, given the 'sometimes'. I don't think that Newton's Law of Gravity (say), with its lovely equation, actually explained anything at all about gravity. Finding the law closes the quest for an accurate description of what happens. |
| 16274 | If the well-ordering of a pack of cards was by shuffling, the explanation would make it more surprising [Lewis] |
| Full Idea: Suppose you find in a hotel room a pack of cards in exactly standard order. Not surprising - maybe it's a new deck, or someone arranged them. Not so. They got that way by being fairly shuffled. The explanation would make the explanandum more surprising. | |
| From: David Lewis (On the Plurality of Worlds [1986], 2.7) | |
| A reaction: [compressed] A lovely Lewisian example, that instantly makes big trouble for the (implausible) view that a cause is something which increases the likelihood of a thing. |
| 19650 | The transcendental subject is not an entity, but a set of conditions making science possible [Meillassoux] |
| Full Idea: The transcendental subject simply cannot be said to exist; which is to say that the subject is not an entity, but rather a set of conditions rendering objective scientific knowledge of entities possible. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 1) | |
| A reaction: Meillassoux treats this as part of the Kantian Disaster, which made an accurate account of the scientific revolution impossible for philosophers. Kant's ego seems to have primarily an epistemological role. |
| 8901 | Abstraction is usually explained either by example, or conflation, or abstraction, or negatively [Lewis] |
| Full Idea: Abstraction is usually explained in one of four ways: the Way of Example (cf. donkeys and numbers), the Way of Conflation (same as sets), the Negative Way (non-spatial and non-causal) or the Way of Abstraction (incomplete descriptions). | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.7) | |
| A reaction: [Compressed; a footnote dismisses Dummett's fifth way] Example has blurred boundaries, and explains nothing. Gerrymandered sets don't produce concepts. Negative accounts explain nothing. So it's the Way of Abstraction! |
| 8904 | The Way of Abstraction says an incomplete description of a concrete entity is the complete abstraction [Lewis] |
| Full Idea: The Way of Abstraction says abstract entities are abstractions from concrete entities; they result from somehow subtracting specificity, so that an incomplete description of the original concrete entity is a complete description of the abstraction. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.7) | |
| A reaction: Defined like this, it rather looks as if abstractions would be entirely verbal - which may well be the correct situation, except that higher animals seem capable of minimal levels of abstraction. This Way is denigrated by Frege and Geach. |
| 8938 | The Way of Example compares donkeys and numbers, but what is the difference, and what are numbers? [Lewis] |
| Full Idea: The Way of Example says concrete entities are things like donkeys and puddles, but abstract entities are things like numbers. That gives us little guidance. There are no uncontroversial accounts of numbers, and donkeys and number differ in too many ways. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.7) | |
| A reaction: That demolishes that fairly swiftly. It may be unfair to demand an agreed account of numbers, but the respect(s) in which donkeys and numbers differ needs to be spelled out before anything useful has been said. |
| 8903 | Abstracta can be causal: sets can be causes or effects; there can be universal effects; events may be sets [Lewis] |
| Full Idea: Is it true that sets or universals cannot enter into causal interaction? Why can't we say that a set of things causes something, or something causes a set of effects? Or positive charge has characteristic effects? Or an event is a sort of set? | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.7) | |
| A reaction: This idea, and 8902, form a devastating critique of attempts to define abstraction in a purely negative way, as non-spatial and non-causal. Only a drastic revision of widely held views about sets, universals and events could save that account. |
| 8902 | If abstractions are non-spatial, then both sets and universals seem to have locations [Lewis] |
| Full Idea: If abstract entities are not located, then a set of things does seem to have a location, though perhaps a divided one; and universals, if they are wholly present in each particular, are where their instances are, so negation can't define abstraction. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.7) | |
| A reaction: He admits that non-spatial accounts of sets and universals are possible, but the jury is out on both of them, and more cautious theories, even if they are realist, will give them both locations. A good argument. |
| 8905 | If universals or tropes are parts of things, then abstraction picks out those parts [Lewis] |
| Full Idea: A theory of non-spatiotemporal parts of things, whether recurring universals or non-recurring tropes, makes good sense of some abstractions. Unit negative charge is a universal common to particles, and an abstraction by being part of them. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.7) | |
| A reaction: He cautiously refers to 'some' abstractions. It is one of Donald Williams's proud boasts concerning his trope theory that it will handle this problem well. I'm not sure that we should be saying that abstractions are actually concrete bits of things. |
| 8906 | If we can abstract the extrinsic relations and features of objects, abstraction isn't universals or tropes [Lewis] |
| Full Idea: Why can't we abstract a highly extrinsic aspect of something, say its surname, or its spatiotemporal location, or its role in a causal network, or its role in some body of theory? But these are unsuitable candidates for being genuine universals or tropes. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.7) | |
| A reaction: (This is a criticism of the proposal in Idea 8905) Obviously we can abstract such things. In particular the role in a causal network is a function, which is a central example of an abstract idea. Russell keeps reminding us that relations are universals. |
| 8907 | The abstract direction of a line is the equivalence class of it and all lines parallel to it [Lewis] |
| Full Idea: We can abstract the direction of a line by taking the direction as the equivalence class of that line and all lines parallel to it. There is no subtraction of detail, but a multiplication of it; by swamping it, the specifics of the original line get lost. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.7) | |
| A reaction: You can ask how wide a line is, but not how wide a direction is, so a detail IS being subtracted. I don't see how you can define the concept of a banana by just saying it is 'every object which is equivalent to a banana'. 'Parallel' is an abstraction. |
| 8908 | For most sets, the concept of equivalence is too artificial to explain abstraction [Lewis] |
| Full Idea: Most sets cannot be regarded as abstractions by equivalence: most sets are equivalence classes only under thoroughly artificial equivalence. (And the empty set is not an equivalence class at all). | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.7) | |
| A reaction: [Recorded for further investigation..] My intuitions certainly cry out against such a thin logical notion giving a decent explanation of such a rich activity as abstraction. |
| 16289 | We can't account for an abstraction as 'from' something if the something doesn't exist [Lewis] |
| Full Idea: We cannot really be talking about the things whence an abstraction-like entity is abstracted if there are no such things. | |
| From: David Lewis (On the Plurality of Worlds [1986], 3.3) | |
| A reaction: Sounds like a killer blow, but I don't think so. I can't think of a concept which doesn't have a possible basis in reality, assuming that it might be a complex assemblage of abstracted components. |
| 16278 | A particular functional role is what gives content to a thought [Lewis] |
| Full Idea: Anything that is a thinker at all has a thought with a certain content in virtue of being in a state which occupies a certain functional role. | |
| From: David Lewis (On the Plurality of Worlds [1986], 2.3) | |
| A reaction: So often Lewis seems to get things the wrong way round. Maybe if you invert his entire (fabulously consistent) philosophy, you get the right answer? I take the content to be what makes the role possible. |
| 9654 | A proposition is a set of entire possible worlds which instantiate a particular property [Lewis] |
| Full Idea: I identify propositions with certain properties - namely, with those that are instantiated only by entire possible worlds. Then if properties generally are the sets of their instances, a proposition is a set of possible worlds. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: I don't get this. How can the proposition that tomatoes are edible be an entire set of possible worlds? The proposition seems to be about tomatoes, and nothing else. Should we talk of 'possibilities', rather than of 'possible worlds'? |
| 15736 | A proposition is the property of being a possible world where it holds true [Lewis] |
| Full Idea: I identify propositions with properties that are instantiated only by entire possible worlds. If properties are the sets of their instances, a proposition is a set of possible worlds. A proposition is the property of being a world where it holds. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: This is so far away from my concept of a proposition (as a truth-evaluable representational mental event) that I struggle to compute it. So the proposition that I am sitting here is the property of 'being the actual world'. Eh? |
| 15738 | Propositions can't have syntactic structure if they are just sets of worlds [Lewis] |
| Full Idea: If it is central to 'proposition' that there be quasi-syntactic structure, so that there are subject-predicate, or negative, or conjunctive, or quantified propositions, then sets of possible worlds will not do. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.5) | |
| A reaction: He proposes 'more complicated set-theoretic constructions out of possibilia' instead. I am very much committed to propositions having quasi-syntactic structure. |
| 9659 | Causation is when at the closest world without the cause, there is no effect either [Lewis] |
| Full Idea: If it is the case at world W that if event C had not occurred, E would not have occurred either, then the counterfactual means that at the closest worlds to W at which C does not occur, E does not occur either. | |
| From: David Lewis (On the Plurality of Worlds [1986], 1.6) | |
| A reaction: This is a very Humean account, though updated, which sees nothing more to causation than transworld regularities. To me that is just describing the evidence for causation, not giving an account of it (even if the latter is impossible). |
| 19667 | If the laws of nature are contingent, shouldn't we already have noticed it? [Meillassoux] |
| Full Idea: The standard objection is that if the laws of nature were actually contingent, we would already have noticed it. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 4) | |
| A reaction: Meillassoux offers a sustained argument that the laws of nature are necessarily contingent. In Idea 19660 he distinguishes contingencies that must change from those that merely could change. |
| 19670 | Why are contingent laws of nature stable? [Meillassoux] |
| Full Idea: We must ask how we are to explain the manifest stability of physical laws, given that we take these to be contingent? | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 4) | |
| A reaction: Meissalloux offers a very deep and subtle answer to this question... It is based on the possibilities of chaos being an uncountable infinity... It is a very nice question, which physicists might be able to answer, without help from philosophy. |
| 9666 | It is quite implausible that the future is unreal, as that would terminate everything [Lewis] |
| Full Idea: It is hard to believe that any philosopher means it when they say the future is unreal. If anyone is right that there is no future, that moment is their last, and it is the end of everything. | |
| From: David Lewis (On the Plurality of Worlds [1986], 4.2) | |
| A reaction: A bit simplistic. I might say 'there will be a future time, but it doesn't exist now'. That's the peculiar thing about time. If I say New York doesn't exist, then clearly I can't visit it. The London 2012 Olympic Stadium is going to exist. |
| 19653 | The ontological proof of a necessary God ensures a reality external to the mind [Meillassoux] |
| Full Idea: Since Descartes conceives of God as existing necessarily, whether I exist to think of him or not, Descartes assures me of a possible access to an absolute reality - a Great Outdoors that is not a correlate of my thought. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 2) | |
| A reaction: His point is that the ontological argument should be seen as part of the scientific revolution, and not an anomaly within it. Interesting. |
| 19658 | Now that the absolute is unthinkable, even atheism is just another religious belief (though nihilist) [Meillassoux] |
| Full Idea: Once the absolute has become unthinkable, even atheism, which also targets God's inexistence in the manner of an absolute, is reduced to a mere belief, and hence to a religion, albeit of the nihilist kind. | |
| From: Quentin Meillassoux (After Finitude; the necessity of contingency [2006], 2) | |
| A reaction: An interesting claim. Rather hard to agree or disagree, though the idea that atheism must qualify as a religion seems odd. If it is unqualified it does have the grand quality of a religion, but if it is fallibilist it just seems like an attitude. |