19 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. |
| 10121 | Contradiction is not a sign of falsity, nor lack of contradiction a sign of truth [Pascal] |
| Full Idea: Contradiction is not a sign of falsity, nor the lack of contradiction a sign of truth. | |
| From: Blaise Pascal (works [1660]), quoted by A.George / D.J.Velleman - Philosophies of Mathematics Ch.6 | |
| A reaction: [Quoted in Auden and Kronenberger's Book of Aphorisms] Presumably we would now say that contradiction is a purely formal, syntactic notion, and not a semantic one. If you hit a contradiction, something has certainly gone wrong. |
| 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. |
| 23438 | Full rationality must include morality [Foot] |
| Full Idea: You haven't got a full idea of rationality until you've got morality within it. | |
| From: Philippa Foot (Interview with Philippa Foot [2003], p.35) | |
| A reaction: Does this mean that mathematical proofs are not rational, or that they are moral? |
| 23437 | Practical reason is goodness in choosing actions [Foot] |
| Full Idea: Practical rationality is goodness in respect of reason for actions, just as rationality of thinking is goodness in respect of beliefs. | |
| From: Philippa Foot (Interview with Philippa Foot [2003], p.35) | |
| A reaction: It is very Greek to think that rationality involves goodness. There seems to be a purely instrumental form of practical reason that just gets from A to B, as when giving accurate street directions to someone. |
| 23436 | It is an odd Humean view to think a reason to act must always involve caring [Foot] |
| Full Idea: One would need a very special, very Humean, view about reasons for actions to think a man doesn't have a reason unless he cares. | |
| From: Philippa Foot (Interview with Philippa Foot [2003], p.34-5) | |
| A reaction: She says she used to believe this, but was wrong. It is hard to imagine acting for reasons if they don't care about anything at all (even that it's their job). But then people just do care about things. |
| 23431 | Human defects are just like plant or animal defects [Foot] |
| Full Idea: We describe defects in human beings in the same way as we do defects in plants and animals. …You cannot talk about a river as being defective. | |
| From: Philippa Foot (Interview with Philippa Foot [2003], p.33) | |
| A reaction: This is a much clearer commitment to naturalistic ethics than I have found in her more academic writings. My opinion of Foot (which was already high) went up when I read this interview. …She says vice is a defect of the will. |
| 23432 | Concepts such as function, welfare, flourishing and interests only apply to living things [Foot] |
| Full Idea: There are concepts which apply only to living things, considered in their own right, which would include function, welfare, flourishing, interests and the good of something. | |
| From: Philippa Foot (Interview with Philippa Foot [2003], p.33) | |
| A reaction: This is a very Aristotelian view, with which I entirely agree. The central concept is function. |
| 23433 | Humans need courage like a plant needs roots [Foot] |
| Full Idea: A plant needs strong roots in the same way human beings need courage. | |
| From: Philippa Foot (Interview with Philippa Foot [2003], p.33) | |
| A reaction: I'm not quite convince by the analogy, but I strongly agree with her basic approach. |
| 23434 | There is no fact-value gap in 'owls should see in the dark' [Foot] |
| Full Idea: If you say 'an owl should be able to see in the dark' …you're not going to think that there's a gap between facts and evaluation. | |
| From: Philippa Foot (Interview with Philippa Foot [2003], p.33) | |
| A reaction: I take this to be a major and fundamental idea, which pinpoints the failure of Humeans to understand the world correctly. There is always total nihilism, of course, but that is a sort of blindness to how things are. Demanding 'proof' of values is crazy. |
| 23439 | Principles are not ultimate, but arise from the necessities of human life [Foot] |
| Full Idea: I don't believe in ultimate principles that must be simply affirmed or denied, but rather in an appeal to the necessities of human life. | |
| From: Philippa Foot (Interview with Philippa Foot [2003], p.37) | |
| A reaction: I agree. Humans have a strong tendency to elevate anything which they consider important into an absolute (such as the value of life, or freedom). |
| 23435 | If you demonstrate the reason to act, there is no further question of 'why should I?' [Foot] |
| Full Idea: You lose the sense of 'should' if you go on saying 'why should I?' when you've finished the argument about what is rational to do, what you've got reason to do. | |
| From: Philippa Foot (Interview with Philippa Foot [2003], P.34) | |
| A reaction: Some people reify the concept of duty, so that they do what is required without caring about the reason. I suppose that would wither if they were shown that no reason exists. |
| 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? |