15 ideas
10928 | 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. |
9565 | Zermelo made 'set' and 'member' undefined axioms [Zermelo, by Chihara] |
Full Idea: The terms 'set' and 'is a member of' are primitives of Zermelo's 1908 axiomatization of set theory. They are not given model-theoretic analyses or definitions. | |
From: report of Ernst Zermelo (works [1920]) by Charles Chihara - A Structural Account of Mathematics 7.5 | |
A reaction: This looks like good practice if you want to work with sets, but not so hot if you are interested in metaphysics. |
3339 | For Zermelo's set theory the empty set is zero and the successor of each number is its unit set [Zermelo, by Blackburn] |
Full Idea: For Zermelo's set theory the empty set is zero and the successor of each number is its unit set. | |
From: report of Ernst Zermelo (works [1920]) by Simon Blackburn - Oxford Dictionary of Philosophy p.280 |
10925 | 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. |
10926 | 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) |
10930 | 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. |
14645 | 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. |
9201 | 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. |
10927 | 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? |
9203 | 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. |
22049 | Transcendental idealism aims to explain objectivity through subjectivity [Bowie] |
Full Idea: The aim of transcendental idealism is to give a basis for objectivity in terms of subjectivity. | |
From: Andrew Bowie (German Philosophy: a very short introduction [2010], 1) | |
A reaction: Hume used subjectivity to undermine the findings of objectivity. There was then no return to naive objectivity. Kant's aim then was to thwart global scepticism. Post-Kantians feared that he had failed. |
22055 | The Idealists saw the same unexplained spontaneity in Kant's judgements and choices [Bowie] |
Full Idea: The Idealist saw in Kant that knowledge, which depends on the spontaneity of judgement, and self-determined spontaneous action, can be seen as sharing the same source, which is not accessible to scientific investigation. | |
From: Andrew Bowie (German Philosophy: a very short introduction [2010]) | |
A reaction: This is the 'spontaneity' of judgements and choices which was seen as the main idea in Kant. It inspired romantic individualism. The judgements are the rule-based application of concepts. |
22054 | German Idealism tried to stop oppositions of appearances/things and receptivity/spontaneity [Bowie] |
Full Idea: A central aim of German Idealism is to overcome Kant's oppositions between appearances and thing in themselves, and between receptivity and spontaneity. | |
From: Andrew Bowie (German Philosophy: a very short introduction [2010], 2) | |
A reaction: I have the impression that there were two strategies: break down the opposition within the self (Fichte), or break down the opposition in the world (Spinozism). |
22056 | Crucial to Idealism is the idea of continuity between receptivity and spontaneous judgement [Bowie] |
Full Idea: A crucial idea for German Idealism (from Hamann) is that apparently passive receptivity and active spontaneity are in fact different degrees of the same 'activity, and the gap between subject and world can be closed. | |
From: Andrew Bowie (German Philosophy: a very short introduction [2010], 3) | |
A reaction: The 'passive' bit seems to be Hume's 'impressions', which are Kant's 'intuitions', which need 'spontaneous' interpretation to become experiences. Critics of Kant said this implied a dualism. |
10931 | 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? |