150 ideas
| 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. |
| 6575 | Philosophy may never find foundations, and may undermine our lives in the process [Fogelin] |
| Full Idea: Not only is traditional philosophy incapable of discovering the foundations it seeks, but the philosophical enterprise may itself dislodge the contingent, de facto supports that our daily life depends upon. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.2) | |
| A reaction: In the end Fogelin is not so pessimistic, but he is worried by the concern of philosophers with paradox and contradiction. I don't remotely consider this a reason to reject philosophy, but it might be a reason to keep it sealed off from daily life. |
| 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. |
| 12274 | Begin examination with basics, and subdivide till you can go no further [Aristotle] |
| Full Idea: The examination must be carried on and begin from the primary classes and then go on step by step until further division is impossible. | |
| From: Aristotle (Topics [c.331 BCE], 109b17) | |
| A reaction: This is a good slogan for the analytic approach to thought. I take Aristotle (or possibly Socrates) to be the father of analysis, not Frege (though see Idea 9840). (He may be thinking of the tableau method of proof). |
| 6585 | Rationality is threatened by fear of inconsistency, illusions of absolutes or relativism, and doubt [Fogelin] |
| Full Idea: The three main threats to our rational lives are fear of inconsistency, illusions (of absolutism and relativism) and doubt. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.4) | |
| A reaction: This is a very nice analysis of the forces that can destroy the philosopher's aspiration to the rational life. Personally I still suffer from a few illusions about the possibility of absolutes, but I may grow out of it. The other three don't bother me. |
| 6557 | Humans may never be able to attain a world view which is both rich and consistent [Fogelin] |
| Full Idea: It might be wholly unreasonable to suppose that human beings will ever be able to attain a view of the world that is both suitably rich and completely consistent. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Intro) | |
| A reaction: Fogelin's lectures develop this view very persuasively. I think all philosophers must believe that the gods could attain a 'rich and consistent' view. Our problem is that we are a badly organised team, whose members keep dying. |
| 6568 | A game can be played, despite having inconsistent rules [Fogelin] |
| Full Idea: The presence of an inconsistency in the rules that govern a game need not destroy the game. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.2) | |
| A reaction: He only defends this thesis if the inconsistency is away from the main centre of the action. You can't have an inconsistent definition of scoring a goal or a touchdown. |
| 6560 | The law of noncontradiction is traditionally the most basic principle of rationality [Fogelin] |
| Full Idea: Traditionally many philosophers (Aristotle among them) have considered the law of noncontradiction to be the deepest, most fundamental principle of rationality. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.1) | |
| A reaction: For Aristotle, see Idea 1601 (and 'Metaphysics' 1005b28). The only denier of the basic character of the law that I know of is Nietzsche (Idea 4531). Fogelin, despite many qualifications, endorses the law, and so do I. |
| 6565 | The law of noncontradiction makes the distinction between asserting something and denying it [Fogelin] |
| Full Idea: People who reject the law of noncontradiction obliterate any significant difference between asserting something and denying it; …this will not move anyone who genuinely opts either for silence or for madness. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.1) | |
| A reaction: This seems a sufficiently firm and clear assertion of the basic nature of this law. The only rival view seems to be that of Nietzsche (Idea 4531), but then you wonder how Nietzsche is in a position to assert the relativity of the law. |
| 12260 | Dialectic starts from generally accepted opinions [Aristotle] |
| Full Idea: Reasoning is dialectical which reasons from generally accepted opinions. | |
| From: Aristotle (Topics [c.331 BCE], 100a30) | |
| A reaction: This is right at the heart of Aristotle's philosophical method, and Greek thinking generally. There are nice modern debates about 'folk' understanding, derived from science (e.g. quantum theory) which suggest that starting from normal views is a bad idea. |
| 12291 | There can't be one definition of two things, or two definitions of the same thing [Aristotle] |
| Full Idea: There cannot possibly be one definition of two things, or two definitions of the same thing. | |
| From: Aristotle (Topics [c.331 BCE], 154a11) | |
| A reaction: The second half of this is much bolder and more controversial, and plenty of modern thinkers would flatly reject it. Are definitions contextual, that is, designed for some specific human purpose. Must definitions be of causes? |
| 12292 | Definitions are easily destroyed, since they can contain very many assertions [Aristotle] |
| Full Idea: A definition is the easiest of all things to destroy; for, since it contains many assertions, the opportunities which it offers are very numerous, and the more abundant the material, the more quickly the reasoning can set to work. | |
| From: Aristotle (Topics [c.331 BCE], 155a03) | |
| A reaction: I quote this to show that Aristotle expected many definitions to be very long affairs (maybe even of book length?) |
| 12272 | We describe the essence of a particular thing by means of its differentiae [Aristotle] |
| Full Idea: We usually isolate the appropriate description of the essence of a particular thing by means of the differentiae which are peculiar to it. | |
| From: Aristotle (Topics [c.331 BCE], 108b05) | |
| A reaction: I take this to be important for showing the definition is more than mere categorisation. A good definition homes in the particular, by gradually narrowing down the differentiae. |
| 12279 | The differentia indicate the qualities, but not the essence [Aristotle] |
| Full Idea: No differentia indicates the essence [ti estin], but rather some quality, such as 'pedestrian' or 'biped'. | |
| From: Aristotle (Topics [c.331 BCE], 122b17) | |
| A reaction: We must disentangle this, since essence is what is definable, and definition seems to give us the essence, and yet it appears that definition only requires genus and differentia. Differentiae seem to be both generic and fine-grained. See Idea 12280! |
| 12283 | In definitions the first term to be assigned ought to be the genus [Aristotle] |
| Full Idea: In definitions the first term to be assigned ought to be the genus. | |
| From: Aristotle (Topics [c.331 BCE], 132a12) | |
| A reaction: We mustn't be deluded into thinking that nothing else is required. I take the increasing refinement of differentiae to be where the real action is. The genus gives you 70% of the explanation. |
| 12289 | The genera and the differentiae are part of the essence [Aristotle] |
| Full Idea: The genera and the differentiae are predicated in the category of essence. | |
| From: Aristotle (Topics [c.331 BCE], 153a19) | |
| A reaction: The definition is words, and the essence is real, so our best definition might not fully attain to the essence. Aristotle has us reaching out to the world through our definitions. |
| 12261 | Differentia are generic, and belong with genus [Aristotle] |
| Full Idea: The differentia, being generic in character, should be ranged with the genus. | |
| From: Aristotle (Topics [c.331 BCE], 101b18) | |
| A reaction: This does not mean that naming the differentia amounts to mere classification. I presume we can only state individual differences by using a language which is crammed full of universals. |
| 12263 | 'Genus' is part of the essence shared among several things [Aristotle] |
| Full Idea: A 'genus' is that which is predicated in the category of essence of several things which differ in kind. | |
| From: Aristotle (Topics [c.331 BCE], 102a32) | |
| A reaction: Hence a genus is likely to be expressed by a universal, a one-over-many. A particular will be a highly individual collection of various genera, but what ensures the uniqueness of each thing, if they are indiscernible? |
| 12285 | The definition is peculiar to one thing, not common to many [Aristotle] |
| Full Idea: The definition ought to be peculiar to one thing, not common to many. | |
| From: Aristotle (Topics [c.331 BCE], 149b24) | |
| A reaction: I take this to be very important, against those who think that definition is no more than mere categorisation. To explain, you must get down to the level of the individual. We must explain that uniquely docile tiger. |
| 6574 | Legal reasoning is analogical, not deductive [Fogelin] |
| Full Idea: There is almost universal agreement that legal reasoning is fundamentally analogical, not deductive, in character. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.2) | |
| A reaction: This raises the question of whether analogy can be considered as 'reasoning' in itself. How do you compare the examples? Could you compare two examples if you lacked language, or rules, or a scale of values? |
| 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? |
| 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? |
| 11261 | Puzzles arise when reasoning seems equal on both sides [Aristotle] |
| Full Idea: The equality of opposite reasonings is the cause of aporia; for it is when we reason on both [sides of a question] and it appears to us that everything can come about either way, that we are in a state of aporia about which of the two ways to take up. | |
| From: Aristotle (Topics [c.331 BCE], 145b17), quoted by Vassilis Politis - Aristotle and the Metaphysics 3.1 | |
| A reaction: Other philosophers give up on the subject in this situation, but I love Aristotle because he takes this to be the place where philosophy begins. |
| 12273 | Unit is the starting point of number [Aristotle] |
| Full Idea: They say that the unit [monada] is the starting point of number (and the point the starting-point of a line). | |
| From: Aristotle (Topics [c.331 BCE], 108b30) | |
| A reaction: Yes, despite Frege's objections in the early part of the 'Grundlagen' (1884). I take arithmetic to be rooted in counting, despite all abstract definitions of number by Frege and Dedekind. Identity gives the unit, which is countable. See also Topics 141b9 |
| 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? |
| 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!] |
| 12267 | There are ten categories: essence, quantity, quality, relation, place, time, position, state, activity, passivity [Aristotle] |
| Full Idea: The four main types of predicates fall into ten categories: essence, quantity, quality, relation, place, time, position, state, activity, passivity. | |
| From: Aristotle (Topics [c.331 BCE], 103b20) | |
| A reaction: These are the standard ten categories of Aristotle. He is notable for the divisions not being sharp, and ten being a rough total. He is well aware of the limits of precision in such matters. |
| 12282 | An individual property has to exist (in past, present or future) [Aristotle] |
| Full Idea: If it does not at present exist, or, if it has not existed in the past, or if it is not going to exist in the future, it will not be a property [idion] at all. | |
| From: Aristotle (Topics [c.331 BCE], 129a27) | |
| A reaction: This seems to cramp our style in counterfactual discussion. Can't we even mention an individual property if we believe that it will never exist. Utopian political discussion will have to cease! |
| 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. |
| 12264 | An 'accident' is something which may possibly either belong or not belong to a thing [Aristotle] |
| Full Idea: An 'accident' [sumbebekos] is something which may possibly either belong or not belong to any one and the self-same thing, such as 'sitting posture' or 'whiteness'. This is the best definition, because it tells us the essential meaning of the term itself. | |
| From: Aristotle (Topics [c.331 BCE], 102b07) | |
| A reaction: Thus a car could be red, or not red. Accidents are contingent. It does not follow that necessary properties are essential (see Idea 12262). There are accidents [sumbebekos], propria [idion] and essences [to ti en einai]. |
| 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. |
| 12280 | Genus gives the essence better than the differentiae do [Aristotle] |
| Full Idea: In assigning the essence [ti estin], it is more appropriate to state the genus than the differentiae; for he who describes 'man' as an 'animal' indicates his essence better than he who describes him as 'pedestrian'. | |
| From: Aristotle (Topics [c.331 BCE], 128a24) | |
| A reaction: See Idea 12279. This idea is only part of the story. My reading of this is simply that assigning a genus gives more information. We learn more about him when we say he is a man than when we say he is Socrates. |
| 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? |
| 13269 | In the case of a house the parts can exist without the whole, so parts are not the whole [Aristotle] |
| Full Idea: In the case of a house, where the process of compounding the parts is obvious, though the parts exist, there is no reason why the whole should not be non-existent, and so the parts are not the same as the whole. | |
| From: Aristotle (Topics [c.331 BCE], 150a19) | |
| A reaction: Compare buying a piece of furniture, and being surprised to discover, when it is delivered, that it is self-assembly. This idea is a simple refutation of the claims of classical mereology, that wholes are just some parts. Aristotle uses modal claims. |
| 12284 | Everything that is has one single essence [Aristotle] |
| Full Idea: Everything that is has one single essence [en esti to einai]. | |
| From: Aristotle (Topics [c.331 BCE], 141a36) | |
| A reaction: Does this include vague objects, and abstract 'objects'? Sceptics might ask what grounds this claim. Does Dr Jeckyll have two essences? |
| 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. |
| 12262 | An 'idion' belongs uniquely to a thing, but is not part of its essence [Aristotle] |
| Full Idea: A property [idion] is something which does not show the essence of a thing but belongs to it alone. ...No one calls anything a property which can possibly belong to something else. | |
| From: Aristotle (Topics [c.331 BCE], 102a18) | |
| A reaction: [See Charlotte Witt 106 on this] 'Property' is clearly a bad translation for such an individual item. Witt uses 'proprium', which is a necessary but nonessential property of something. Necessity is NOT the hallmark of essence. See Idea 12266. |
| 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? ... |
| 12290 | Destruction is dissolution of essence [Aristotle] |
| Full Idea: Destruction is a dissolution of essence. | |
| From: Aristotle (Topics [c.331 BCE], 153b30) | |
| A reaction: [plucked from context!] I can't think of a better way to define destruction, in order to distinguish it from damage. A vase is destroyed when its essential function cannot be recovered. |
| 12286 | If two things are the same, they must have the same source and origin [Aristotle] |
| Full Idea: When things are absolutely the same, their coming-into-being and destruction are also the same and so are the agents of their production and destruction. | |
| From: Aristotle (Topics [c.331 BCE], 152a02) | |
| A reaction: Thus Queen Elizabeth II has to be the result of that particular birth, and from those particular parents, as Kripke says? The inverse may not be true. Do twins have a single origin? Things that fission and then re-fuse differently? etc |
| 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'. |
| 12266 | 'Same' is mainly for names or definitions, but also for propria, and for accidents [Aristotle] |
| Full Idea: 'The same' is employed in several senses: its principal sense is for same name or same definition; a second sense occurs when sameness is applied to a property [idiu]; a third sense is applied to an accident. | |
| From: Aristotle (Topics [c.331 BCE], 103a24-33) | |
| A reaction: [compressed] 'Property' is better translated as 'proprium' - a property unique to a particular thing, but not essential - see Idea 12262. Things are made up of essence, propria and accidents, and three ways of being 'the same' are the result. |
| 12287 | Two identical things have the same accidents, they are the same; if the accidents differ, they're different [Aristotle] |
| Full Idea: If two things are the same then any accident of one must also be an accident of the other, and, if one of them is an accident of something else, so must the other be also. For, if there is any discrepancy on these points, obviously they are not the same. | |
| From: Aristotle (Topics [c.331 BCE], 152a36) | |
| A reaction: So what is always called 'Leibniz's Law' should actually be 'Aristotle's Law'! I can't see anything missing from the Aristotle version, but then, since most people think it is pretty obvious, you would expect the great stater of the obvious to get it. |
| 12288 | Numerical sameness and generic sameness are not the same [Aristotle] |
| Full Idea: Things which are the same specifically or generically are not necessarily the same or cannot possibly be the same numerically. | |
| From: Aristotle (Topics [c.331 BCE], 152b32) | |
| A reaction: See also Idea 12266. This looks to me to be a pretty precise anticipation of Peirce's type/token distinction, but without the terminology. It is reassuring that Aristotle spotted it, as that makes it more likely to be a genuine distinction. |
| 12259 | Reasoning is when some results follow necessarily from certain claims [Aristotle] |
| Full Idea: Reasoning [sullogismos] is a discussion in which, certain things having been laid down, something other than these things necessarily results through them. | |
| From: Aristotle (Topics [c.331 BCE], 100a25) | |
| A reaction: This is cited as the standard statement of the nature of logical necessity. One might challenge either the very word 'necessary', or the exact sense of the word employed here. Is it, in fact, metaphysical, or merely analytic? |
| 6582 | Conventions can only work if they are based on something non-conventional [Fogelin] |
| Full Idea: Convention, to exist at all, must have a basis in something that is not conventional; conventions, to work, need something nonconventional to build upon and shape. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.3) | |
| A reaction: Fogelin attributes his point to Hume. I agree entirely. No convention could ever possibly catch on in a society unless there were some point to it. If you can't see a point to a convention (like wearing ties) then start looking, because it's there. |
| 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. |
| 6576 | My view is 'circumspect rationalism' - that only our intellect can comprehend the world [Fogelin] |
| Full Idea: My own view might be called 'circumspect rationalism' - the view that our intellectual faculties provide our only means for comprehending the world in which we find oruselves. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.3) | |
| A reaction: He needs to say more than that to offer a theory, but I like the label, and it fits the modern revival of rationalism, with which I sympathise, and which rests, I think, on Russell's point that self-evidence comes in degrees, not as all-or-nothing truth. |
| 6589 | Knowledge is legitimate only if all relevant defeaters have been eliminated [Fogelin] |
| Full Idea: In general a knowledge claim is legitimate only if all relevant defeaters have been eliminated. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.4) | |
| A reaction: The problem here is what is 'relevant'. Fogelin's example is 'Are you sure the suspect doesn't have a twin brother?' If virtual reality is relevant, most knowledge is defeated. Certainly, imaginative people feel that they know less than others. |
| 6596 | For coherentists, circularity is acceptable if the circle is large, rich and coherent [Fogelin] |
| Full Idea: Coherentists argue that if the circle of justifications is big enough, rich enough, coherent enough, and so on, then there is nothing wrong circularity. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.4) | |
| A reaction: There must always be something wrong with circularity, and no god would put up with it, but we might have to. Of course, two pieces of evidence might be unconnected, such as an equation and an observation. |
| 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. |
| 6597 | A rule of justification might be: don't raise the level of scrutiny without a good reason [Fogelin] |
| Full Idea: One rule for the justification of knowledge might be: Do not raise the level of scrutiny in the absence of a particular reason that triggers it. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.4) | |
| A reaction: That won't decide the appropriate level of scrutiny from which to start. One of my maxims is 'don't set the bar too high', but it seems tough that one should have to justify moving it. The early scientists tried raising it, and were amazed by the results. |
| 6588 | Scepticism is cartesian (sceptical scenarios), or Humean (future), or Pyrrhonian (suspend belief) [Fogelin] |
| Full Idea: The three forms of scepticism are cartesian, Humean and Pyrrhonian. The first challenges belief by inventing sceptical scenarios; the second doubts the future; the third aims to suspend belief. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.4) | |
| A reaction: A standard distinction is made between methodological and global scepticism. The former seems to be Cartesian, and the latter Pyrrhonian. The interest here is see Hume placed in a distinctive category, because of his views on induction. |
| 6590 | Scepticism deals in remote possibilities that are ineliminable and set the standard very high [Fogelin] |
| Full Idea: Sceptical scenarios deal in wildly remote defeating possibilities, so that the level of scrutiny becomes unrestrictedly high, and they also usually deal with defeators that are in principle ineliminable. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.4) | |
| A reaction: The question of how high we 'set the bar' seems to me central to epistemology. There is clearly an element of social negotiation involved, centring on what is appropriate. If, though, scepticism is 'ineliminable', we must face up to that. |
| 6583 | Radical perspectivism replaces Kant's necessary scheme with many different schemes [Fogelin] |
| Full Idea: We reach radical perspectivism by replacing Kant's single, necessary categorial scheme with a plurality of competing categorial schemes. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.3) | |
| A reaction: It certainly looks as if Kant sent us down a slippery slope into the dafter aspects of twentieth century relativism. The best antidote I know of is Davidson's (e.g. Idea 6398). But then it seems unimaginative to say that only one scheme is possible. |
| 12271 | Induction is the progress from particulars to universals [Aristotle] |
| Full Idea: Induction is the progress from particulars to universals; if the skilled pilot is the best pilot and the skilled charioteer the best charioteer, then, in general, the skilled man is the best man in any particular sphere. | |
| From: Aristotle (Topics [c.331 BCE], 105a15) | |
| A reaction: It is a bit unclear whether we are deriving universal concepts, or merely general truths. Need general truths be absolute or necessary truths? Presumably occasionally the best person is not the most skilled, as in playing a musical instrument. |
| 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. |
| 12293 | We say 'so in cases of this kind', but how do you decide what is 'of this kind'? [Aristotle] |
| Full Idea: When it is necessary to establish the universal, people use the expression 'So in all cases of this kind'; but it is one of the most difficult tasks to define which of the terms proposed are 'of this kind' and which are not. | |
| From: Aristotle (Topics [c.331 BCE], 157a25) | |
| A reaction: It is particularly hard if induction is expressed as the search for universals, since the kind presumably is the universal, so the universal must be known before the induction can apply, which really is the most frightful nuisance for truth-seekers. |
| 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. |
| 6555 | We are also irrational, with a unique ability to believe in bizarre self-created fictions [Fogelin] |
| Full Idea: We as human beings are also irrational animals, unique among animals in our capacity to place faith in bizarre fictions of our own construction. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Intro) | |
| A reaction: This is glaringly true, and a very nice corrective to the talk of Greeks and others about man as the 'rational animal'. From a distance we might be described by Martians as the 'mad animal'. Is the irrational current too strong to swim against? |
| 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. |
| 6605 | Critics must be causally entangled with their subject matter [Fogelin] |
| Full Idea: Critics must become causally entangled with their subject matter. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.6) | |
| A reaction: This remark is built on Hume's views. You may have a strong view about a singer, but it may be hard to maintain when someone plays you six rival versions of the same piece. I agree entirely with the remark. It means there are aesthetic experts. |
| 6607 | The word 'beautiful', when deprived of context, is nearly contentless [Fogelin] |
| Full Idea: Like the word 'good', the word 'beautiful', when deprived of contextual support, is nearly contentless. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.6) | |
| A reaction: If I say with, for example, Oscar Wilde that beauty is the highest ideal in life, this doesn't strike me as contentless, but I still sympathise with Fogelin's notion that beauty is rooted in particulars. |
| 6604 | Saying 'It's all a matter to taste' ignores the properties of the object discussed [Fogelin] |
| Full Idea: "It is all a matter of taste" may be an all-purpose stopper of discussions of aesthetic values, but it also completely severs the connection with the actual properties of the object under consideration. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.6) | |
| A reaction: This remark grows out of his discussion of Hume. I like this remark, which ties in with Particularism in morality, and with the central role of experiments in science. The world forces beliefs on us. |
| 6586 | Cynics are committed to morality, but disappointed or disgusted by human failings [Fogelin] |
| Full Idea: Cynics are usually unswerving in their commitment to a moral ideal, but disappointed or disgusted by humanity's failure to meet it. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.3) | |
| A reaction: I felt quite suicidal the other day when I saw someone park diagonally across two parking spaces. They can't seem to grasp the elementary Kantian slogan 'What if everybody did that?' It's all hopeless. I wonder if I am becoming a bit of a Cynic? |
| 12277 | Friendship is preferable to money, since its excess is preferable [Aristotle] |
| Full Idea: Friendship is preferable to money; for excess of friendship is preferable to excess of money. | |
| From: Aristotle (Topics [c.331 BCE], 118b07) | |
| A reaction: Compare Idea 12276, which gives a different criterion for choosing between virtues. This idea is an interesting qualification of the doctrine of the mean. |
| 12276 | Justice and self-control are better than courage, because they are always useful [Aristotle] |
| Full Idea: Justice [dikaiosune] and self-control [sophrosune] are preferable to courage, for the first two are always useful, but courage only sometimes. | |
| From: Aristotle (Topics [c.331 BCE], 117a36) | |
| A reaction: One could challenge his criterion. What of something which is absolutely vital on occasions, against something which is very mildly useful all the time? You may survive without justice, but not without courage. Compare Idea 12277. |
| 12275 | We value friendship just for its own sake [Aristotle] |
| Full Idea: We value friendship for its own sake, even if we are not likely to get anything else from it. | |
| From: Aristotle (Topics [c.331 BCE], 117a03) | |
| A reaction: In 'Ethics' he distinguishes some friendships which don't meet this requirement. Presumably true friendships survive all vicissitudes (except betrayal), but that makes such things fairly rare. |
| 12281 | Man is intrinsically a civilized animal [Aristotle] |
| Full Idea: It is an essential [kath' auto] property of man to be 'by nature a civilized animal'. | |
| From: Aristotle (Topics [c.331 BCE], 128b17) | |
| A reaction: I take this, along with man being intrinsically rational, to be the foundation of Aristotelian ethics. Given that we are civilized, self-evident criteria emerge for how to be good at it. A good person is, above all, a good citizen. |
| 6572 | Deterrence, prevention, rehabilitation and retribution can come into conflict in punishments [Fogelin] |
| Full Idea: The purposes of punishment include deterrence, prevention, rehabilitation, and retribution, but they don't always sit well together. Deterrence is best served by making prisons miserable places, but this may run counter to rehabilitation. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.2) | |
| A reaction: It seems to most educated people that retribution should be pushed far down the list if we are to be civilised (see Idea 1659), and yet personal revenge for a small act of aggression seems basic, normal and acceptable. We dream of rehabilitation. |
| 6573 | Retributivists say a crime can be 'paid for'; deterrentists still worry about potential victims [Fogelin] |
| Full Idea: A strict retributivist is likely to say that once a crime is paid for, that's that; a deterrence theorist is likely to say that the protection of potential victims overrides the released convict's right to a free and fresh start. | |
| From: Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.2) | |
| A reaction: Interesting since the retributivist here has the more liberal attitude. Reformists will also have a dilemma when years in prison have failed to reform the convict. Virtue theorists like balance, and sensitively consider our relations with the criminals. |
| 12265 | All water is the same, because of a certain similarity [Aristotle] |
| Full Idea: Any water is said to be specifically the same as any other water because it has a certain similarity to it. | |
| From: Aristotle (Topics [c.331 BCE], 103a20) | |
| A reaction: (Cf. Idea 8153) It take this to be the hallmark of a natural kind, and we should not lose sight of it in the midst of discussions about rigid designation and essential identity. Tigers are only a natural kind insofar as they are indistinguishable. |
| 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). |
| 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. |
| 12278 | 'Being' and 'oneness' are predicated of everything which exists [Aristotle] |
| Full Idea: 'Being' and 'oneness' are predicated of everything which exists. | |
| From: Aristotle (Topics [c.331 BCE], 121a18) | |
| A reaction: Is 'oneness' predicated of water? So existence always was a predicate, it seems, until Kant told us it wasn't. That existence is a quantifier, not a predicate, seems to be up for question again these days. |