22 ideas
22438 | Philosophy is largely concerned with finding the minimum that science could get by with [Quine] |
Full Idea: Philosophy is in large part concerned with ...what science could get along with, could be reconstructed by means of, as distinct from what science has historically made us of. | |
From: Willard Quine (Mr Strawson on Logical Theory [1953], V) | |
A reaction: This nicely summarises the programme for the whole of the philosophy of David Lewis, who was Quine's pupil. If you start by asking what it could 'get by with', it is not surprising that simplicity is the top intellectual virtue for both of them. |
22436 | Logicians don't paraphrase logic into language, because they think in the symbolic language [Quine] |
Full Idea: The logician does not even need to paraphrase the vernacular into his logical notation, for he has learned to think directly in his logical notation, or even (which is the beauty of the thing) to let it think for him. | |
From: Willard Quine (Mr Strawson on Logical Theory [1953], V) | |
A reaction: See Williamson's love of logic (and his book on modal metaphysics). This idea embodies the dream of hardcore Frege-Russellian analytic philosophers. I wish someone had told me when I studied logic that the target was to actually think symbolically. |
22431 | Good algorithms and theories need many occurrences of just a few elements [Quine] |
Full Idea: The power and simplicity of an algorithm, or indeed of any theory, depend on there being many occurrences of few elements rather than few occurrences of many. | |
From: Willard Quine (Mr Strawson on Logical Theory [1953], III) | |
A reaction: Not sure how this applies to a software function. One which produces a good result from a large number of input variables sounds particularly impressive to me. Many occurrences of a single variable sounds rather inefficient. |
22435 | The logician's '→' does not mean the English if-then [Quine] |
Full Idea: The logician drops 'if-then' in favour of '→' without ever entertaining the mistaken idea that they are synonymous. | |
From: Willard Quine (Mr Strawson on Logical Theory [1953], V) | |
A reaction: [Quine uses the older horseshoe symbol] The conditional in English is not well understood, whereas the symbol is unambiguous. A warning to myself, since I have a tendency to translate symbols into English all the time. [p.156 'implies' is worse!] |
22433 | It is important that the quantification over temporal entities is timeless [Quine] |
Full Idea: It would be hard to exaggerate the importance of recognising the timelessness of quantification over temporal entities. | |
From: Willard Quine (Mr Strawson on Logical Theory [1953], IV) | |
A reaction: 'Some moments in this cricket match were crucial'. The domain is not timeless, but consists of moments in this match. Can you say the quantifier is timeless but its domain is not? Only in the sense that 'very' is a timeless word, I think. |
22437 | Logical languages are rooted in ordinary language, and that connection must be kept [Quine] |
Full Idea: A logical language is not independent of ordinary language. It has its roots in ordinary language, and these roots are not to be severed. | |
From: Willard Quine (Mr Strawson on Logical Theory [1953], V) | |
A reaction: Music to my ears. When you study logic, no one has to teach you what the words 'or' and 'if-then' mean, but they are disambiguated by the symbolism. The roots of logic are in ordinary talk of 'and', 'or' and 'not', which is the real world. |
22434 | Reduction to logical forms first simplifies idioms and grammar, then finds a single reading of it [Quine] |
Full Idea: Ordinary language is reduced to logical form in two ways: reduction of the variety of idioms and grammatical constructions, and reduction of each surviving idiom to one fixed and convenient interpretation. | |
From: Willard Quine (Mr Strawson on Logical Theory [1953], V) | |
A reaction: Is there a conflict between a 'fixed' and a 'convenient' result? By 'fixed' I suppose he means it is a commitment (to not waver). What is the logical form of a sentence which is deliberately ambiguous? |
11976 | 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. |
11978 | 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? |
14919 | Empiricists deny what is unobservable, and reject objective modality [Fraassen] |
Full Idea: To be an empiricist is to withhold belief in anything that goes beyond the actual, observable phenomena, and to recognise no objective modality in nature. | |
From: Bas C. van Fraassen (The Scientific Image [1980], p.202), quoted by J Ladyman / D Ross - Every Thing Must Go 2.3.1 | |
A reaction: To only believe in what is actually observable strikes me as ridiculous. It might be, though, that we observe modality, in observing dispositions. If you pull back a bowstring, you feel the possibilities. |
22432 | Normally conditionals have no truth value; it is the consequent which has a conditional truth value [Quine] |
Full Idea: Ordinarily the conditional is not thought of as true or false at all, but rather the consequent is thought of as conditionally true or false given the antecedent. | |
From: Willard Quine (Mr Strawson on Logical Theory [1953], III) | |
A reaction: At first this seems obvious, but a conditional asserts a relationship between two propositions, and so presumably it is true if that relationship exists. 'Is it actually true that if it is Monday then everyone in the office is depressed?'. |
11979 | 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. |
16994 | 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. |
11974 | 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. |
11975 | 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. |
11977 | 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. |
6783 | To 'accept' a theory is not to believe it, but to believe it empirically adequate [Fraassen, by Bird] |
Full Idea: To 'accept' a theory is not to believe it, but is instead to believe it to be empirically adequate. | |
From: report of Bas C. van Fraassen (The Scientific Image [1980]) by Alexander Bird - Philosophy of Science Ch.4 | |
A reaction: The second half of this doesn't avoid the word 'belief'. Nevertheless the suggestion is that we never believe (i.e. commit to truth) ever again. So you avoid an on-coming bus because the threat appears to be 'empirically adequate'. Hm. |
14917 | To accept a scientific theory, we only need to believe that it is empirically adequate [Fraassen] |
Full Idea: Science aims to give us theories which are empirically adequate; and acceptance of a theory involves as belief only that it is empiricially adequate. | |
From: Bas C. van Fraassen (The Scientific Image [1980], p.12), quoted by J Ladyman / D Ross - Every Thing Must Go 2.3.1 | |
A reaction: This won't tell us what to do if there is a tie between two theories, and we will want to know the criteria for 'adequate'. Presumably there are theories which are empirically quite good, but not yet acceptable. Theories commit beyond experience. |
6784 | Why should the true explanation be one of the few we have actually thought of? [Fraassen, by Bird] |
Full Idea: Van Fraassen asks why we should think that the actual explanation of the evidence should be found among the theories we are considering, when there must be an infinity of theories which are also potential explanations of the evidence? | |
From: report of Bas C. van Fraassen (The Scientific Image [1980]) by Alexander Bird - Philosophy of Science Ch.4 | |
A reaction: This has become one of the leading modern anti-realist arguments. We must introduce an element of faith here; presumably evolution makes us experts on immediate puzzles, competent on intermediate ones, and hopeful on remote ones. |
13066 | An explanation is just descriptive information answering a particular question [Fraassen, by Salmon] |
Full Idea: On van Fraassen's theory an explanation is simply an answer to a why-question; it is nothing other than descriptive information that, in a given context, answers a particular type of question. | |
From: report of Bas C. van Fraassen (The Scientific Image [1980]) by Wesley Salmon - Four Decades of Scientific Explanation 4.3 | |
A reaction: Presumably we would need some sort of criterion for a 'good' explanation, and it seems to me that a very good explanation might be given which was nevertheless beyond the grasp of the questioner. |
22430 | If we understand a statement, we know the circumstances of its truth [Quine] |
Full Idea: We understand under what circumstances to say of any given statement that it is true, just as clearly as we understand the statement itself. | |
From: Willard Quine (Mr Strawson on Logical Theory [1953], II) | |
A reaction: This probably shouldn't be taken as a theory of meaning (in which Quine doesn't really believe) but as a plausible statement of correlated facts. Hypothetical assertions might be a problem case. 'If only I could be in two places at once'? |
13713 | Quine holds time to be 'space-like': past objects are as real as spatially remote ones [Quine, by Sider] |
Full Idea: Quine's view is that time is 'space-like'. Past objects are as real as present ones; they're just temporally distant, just as spatially distant objects are just as real as the ones around here. | |
From: report of Willard Quine (Mr Strawson on Logical Theory [1953]) by Theodore Sider - Logic for Philosophy 7.3.1 | |
A reaction: Something is a wrong with a view that says that a long-dead person is just as real as one currently living. Death is rather more than travelling to a distant place. Arthur Prior responded to Quine by saying 'tense operators' are inescapable. |