Combining Texts

All the ideas for 'Counterpart theory and Quant. Modal Logic', 'Reference and Modality' and 'On Plural Reference and Set Theory'

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17 ideas

4. Formal Logic / D. Modal Logic ML / 1. Modal Logic
Maybe we can quantify modally if the objects are intensional, but it seems unlikely [Quine]
     Full Idea: Perhaps there is no objection to quantifying into modal contexts as long as the values of any variables thus quantified are limited to intensional objects, but they also lead to disturbing examples.
     From: Willard Quine (Reference and Modality [1953], §3)
     A reaction: [Quine goes on to give his examples] I take it that possibilities are features of actual reality, not merely objects of thought. The problem is that they are harder to know than actual objects.
5. Theory of Logic / F. Referring in Logic / 1. Naming / b. Names as descriptive
Failure of substitutivity shows that a personal name is not purely referential [Quine]
     Full Idea: Failure of substitutivity shows that the occurrence of a personal name is not purely referential.
     From: Willard Quine (Reference and Modality [1953], §1)
     A reaction: I don't think I understand the notion of a name being 'purely' referential, as if it somehow ceased to be a word, and was completely transparent to the named object.
5. Theory of Logic / F. Referring in Logic / 1. Naming / d. Singular terms
A 'singulariser' converts a plural like 'number of' to a syntactically neutral form [Cartwright,H, by Hossack]
     Full Idea: Helen Cartwright calls 'a number of' a 'singulariser', an expression whose linguistic function is to convert to a syntactically neutral form an expression whose semantic value remains plural. It is a great convenience grammatically.
     From: report of Helen Cartwright (On Plural Reference and Set Theory [1993]) by Keith Hossack - Plurals and Complexes 2
     A reaction: Compare Hofweber's Idea 10004, suggesting it is a crucial psychological convenience for reasoning, as well as a 'grammatical' convenience.
5. Theory of Logic / G. Quantification / 1. Quantification
Quantifying into referentially opaque contexts often produces nonsense [Quine]
     Full Idea: If to a referentially opaque context of a variable we apply a quantifier, with the intention that it govern that variable from outside the referentially opaque context, then what we commonly end up with is unintended sense or nonsense.
     From: Willard Quine (Reference and Modality [1953], §2)
9. Objects / D. Essence of Objects / 1. Essences of Objects
Aristotelian essentialism says essences are not relative to specification [Lewis]
     Full Idea: So-called 'Aristotelian essentialism' is the doctrine of essences not relative to specifications.
     From: David Lewis (Counterpart theory and Quant. Modal Logic [1968], III)
     A reaction: In other words, they are so-called 'real essences', understood as de re. Quine says essences are all de dicto, and relative to some specification. I vote for Aristotle.
9. Objects / D. Essence of Objects / 15. Against Essentialism
Quantification into modal contexts requires objects to have an essence [Quine]
     Full Idea: A reversion to Aristotelian essentialism is required if quantification into modal contexts is to be insisted on. An object must be seen as having some of its traits necessarily.
     From: Willard Quine (Reference and Modality [1953], §3)
     A reaction: This thought leads directly to Kripke's proposal of rigid designation of objects (and Lewis response of counterparts), which really gets modal logic off the ground. Quine's challenge remains - the modal logic entails a huge metaphysical commitment.
10. Modality / A. Necessity / 4. De re / De dicto modality
To be necessarily greater than 7 is not a trait of 7, but depends on how 7 is referred to [Quine]
     Full Idea: To be necessarily greater than 7 is not a trait of a number, but depends on the manner of referring to the number.
     From: Willard Quine (Reference and Modality [1953], §2)
     A reaction: The most concise quotation of Quine's objection to 'de re' modality. The point is whether the number might have been referred to as 'the number of planets'. So many of these problems are solved by fixing unambiguous propositions first.
10. Modality / A. Necessity / 7. Natural Necessity
Causal necessities hold in all worlds compatible with the laws of nature [Lewis]
     Full Idea: Just as a sentence is necessary if it holds in all worlds, so it is causally necessary if it holds in all worlds compatible with the laws of nature.
     From: David Lewis (Counterpart theory and Quant. Modal Logic [1968], V)
     A reaction: I don't believe in the so-called 'laws of nature', so I'm not buying that. Is there no distinction in Lewis's view between those sentences which must hold, and those which happen to hold universally?
10. Modality / A. Necessity / 11. Denial of Necessity
Whether 9 is necessarily greater than 7 depends on how '9' is described [Quine, by Fine,K]
     Full Idea: Quine's metaphysical argument is that if 9 is 7+2 the number 9 will be necessarily greater than 7, but when 9 is described as the number of planets, the number will not be necessarily greater than 7. The necessity depends on how it is described.
     From: report of Willard Quine (Reference and Modality [1953]) by Kit Fine - Intro to 'Modality and Tense' p. 3
     A reaction: Thus necessity would be entirely 'de dicto' and not 'de re'. It sounds like a feeble argument. If I describe the law of identity (a=a) as 'my least favourite logical principle', that won't make it contingent. Describe 9, or refer to it? See Idea 9203.
Necessity only applies to objects if they are distinctively specified [Quine]
     Full Idea: Necessity does not properly apply to the fulfilment of conditions by objects (such as the number which numbers the planets), apart from special ways of specifying them.
     From: Willard Quine (Reference and Modality [1953], §3)
     A reaction: This appears to say that the only necessity is 'de dicto', and that there is no such thing as 'de re' necessity (of the thing in itself). How can Quine deny that there might be de re necessities? His point is epistemological - how can we know them?
10. Modality / E. Possible worlds / 3. Transworld Objects / a. Transworld identity
We can't quantify in modal contexts, because the modality depends on descriptions, not objects [Quine, by Fine,K]
     Full Idea: 'Necessarily 9>7' may be true while the sentence 'necessarily the number of planets < 7' is false, even though it is obtained by substituting a coreferential term. So quantification in these contexts is unintelligible, without a clear object.
     From: report of Willard Quine (Reference and Modality [1953]) by Kit Fine - Intro to 'Modality and Tense' p. 4
     A reaction: This is Quine's second argument against modality. See Idea 9201 for his first. Fine attempts to refute it. The standard reply seems to be to insist that 9 must therefore be an object, which pushes materialist philosophers into reluctant platonism.
10. Modality / E. Possible worlds / 3. Transworld Objects / b. Rigid designation
It doesn't take the whole of a possible Humphrey to win the election [Lewis]
     Full Idea: Even if Humphrey is a modal continuant, it doesn't take the whole of him to do such things as winning.
     From: David Lewis (Counterpart theory and Quant. Modal Logic [1968], Post B)
     A reaction: This responds to Kripke's famous example, that people only care about what happens to themselves, and not to some 'counterpart' of themselves.
10. Modality / E. Possible worlds / 3. Transworld Objects / c. Counterparts
Counterpart theory is bizarre, as no one cares what happens to a mere counterpart [Kripke on Lewis]
     Full Idea: Probably Humphrey could not care less whether someone else, no matter how much resembling him, would have been victorious in another possible world. Thus Lewis's view seems even more bizarre that the usual transworld identification it replaces.
     From: comment on David Lewis (Counterpart theory and Quant. Modal Logic [1968]) by Saul A. Kripke - Naming and Necessity notes and addenda note 13
     A reaction: I begin to see this as a devastating reply to a theory I previously found quite congenial.
Counterparts are not the original thing, but resemble it more than other things do [Lewis]
     Full Idea: Your counterparts resemble you closely in content and context in important respects. They resemble you more closely than do the other things in their worlds. But they are not really you.
     From: David Lewis (Counterpart theory and Quant. Modal Logic [1968], I)
     A reaction: It is a dilemma. If my counterpart were exactly me, I couldn't contemplate possibly losing a leg, or my sanity. But if my counterpart isn't exactly me, then I don't have much interest in its fate. Only essences can save us here. Cf. me tomorrow.
If the closest resembler to you is in fact quite unlike you, then you have no counterpart [Lewis]
     Full Idea: If whatever thing in world w6 it is that resembles you more closely than anything else in w6 is nevertheless quite unlike you; nothing in w6 resembles you at all closely. If so, you have no counterpart in w6.
     From: David Lewis (Counterpart theory and Quant. Modal Logic [1968], I)
     A reaction: This is the nub, because the whole theory rests on deciding whether two things resemble sufficiently 'closely'. But then we need a criterion of closeness, so we must start talking about which properties matter. Essences loom.
Essential attributes are those shared with all the counterparts [Lewis]
     Full Idea: An essential attribute of something is an attribute it shares with all its counterparts.
     From: David Lewis (Counterpart theory and Quant. Modal Logic [1968], III)
     A reaction: I don't like this. It ties essence entirely to identity, but I think essence precedes identity. Essence is a nexus of causal and explanatory powers which bestows an identity on each thing. But essence might be unstable, and identity with it.
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / e. Anti scientific essentialism
We can't say 'necessarily if x is in water then x dissolves' if we can't quantify modally [Quine]
     Full Idea: To say an object is soluble in water is to say that it would dissolve if it were in water,..which implies that 'necessarily if x is in water then x dissolves'. Yet we do not know if there is a suitable sense of 'necessarily' into which we can so quantify.
     From: Willard Quine (Reference and Modality [1953], §4)
     A reaction: This is why there has been a huge revival of scientific essentialism - because Krike seems to offer exacty the account which Quine said was missing. So can you have modal logic without rigid designation?