15 ideas
| 9406 | A class is natural when everybody can spot further members of it [Quinton] |
| Full Idea: To say that a class is natural is to say that when some of its members are shown to people they pick out others without hesitation and in agreement. | |
| From: Anthony Quinton (The Nature of Things [1973], 9 'Nat') | |
| A reaction: He concedes a number of problems with his view, but I admire his attempt to at least begin to distinguish the natural (real!) classes from the ersatz ones. A mention of causal powers would greatly improve his story. |
| 11211 | If a sound conclusion comes from two errors that cancel out, the path of the argument must matter [Rumfitt] |
| Full Idea: If a designated conclusion follows from the premisses, but the argument involves two howlers which cancel each other out, then the moral is that the path an argument takes from premisses to conclusion does matter to its logical evaluation. | |
| From: Ian Rumfitt ("Yes" and "No" [2000], II) | |
| A reaction: The drift of this is that our view of logic should be a little closer to the reasoning of ordinary language, and we should rely a little less on purely formal accounts. |
| 11210 | Standardly 'and' and 'but' are held to have the same sense by having the same truth table [Rumfitt] |
| Full Idea: If 'and' and 'but' really are alike in sense, in what might that likeness consist? Some philosophers of classical logic will reply that they share a sense by virtue of sharing a truth table. | |
| From: Ian Rumfitt ("Yes" and "No" [2000]) | |
| A reaction: This is the standard view which Rumfitt sets out to challenge. |
| 11212 | The sense of a connective comes from primitively obvious rules of inference [Rumfitt] |
| Full Idea: A connective will possess the sense that it has by virtue of its competent users' finding certain rules of inference involving it to be primitively obvious. | |
| From: Ian Rumfitt ("Yes" and "No" [2000], III) | |
| A reaction: Rumfitt cites Peacocke as endorsing this view, which characterises the logical connectives by their rules of usage rather than by their pure semantic value. |
| 15730 | Extreme nominalists say all classification is arbitrary convention [Quinton] |
| Full Idea: Pure, extreme nominalism sees all classification as the product of arbitrary convention. | |
| From: Anthony Quinton (The Nature of Things [1973], 9 'Nat') | |
| A reaction: I'm not sure what the word 'arbitrary' is doing there. Nominalists are not daft, and if they can classify any way they like, they are not likely to choose an 'arbitrary' system. Pragmatism tells the right story here. |
| 15728 | The naturalness of a class depends as much on the observers as on the objects [Quinton] |
| Full Idea: The naturalness of a class depends as essentially on the nature of the observers who classify as it does on the nature of the objects that they classify. ...It depends on our perceptual apparatus, and on our relatively mutable needs and interests. | |
| From: Anthony Quinton (The Nature of Things [1973], 9 'Nat') | |
| A reaction: This seems to translate 'natural' as 'natural for us', which is not much use to scientists, who spend quite a lot of effort combating folk wisdom. Do desirable sports cars constitute a natural class? |
| 9407 | Properties imply natural classes which can be picked out by everybody [Quinton] |
| Full Idea: To say there are properties is to say there are natural classes, classes introduction to some of whose members enables people to pick out others without hesitation and in agreement. | |
| From: Anthony Quinton (The Nature of Things [1973], 9 'Nat') | |
| A reaction: Aristotle would like this approach, but it doesn't find many friends among modern logician/philosophers. We should go on to ask why people agree on these things. Causal powers will then come into it. |
| 15729 | Uninstantiated properties must be defined using the instantiated ones [Quinton] |
| Full Idea: Properties that have no concrete instances must be defined in terms of those that have. | |
| From: Anthony Quinton (The Nature of Things [1973], 9 'Nat') | |
| A reaction: I wonder what the dodo used to smell like? |
| 8520 | An individual is a union of a group of qualities and a position [Quinton, by Campbell,K] |
| Full Idea: Quinton proposes that an individual is a union of a group of qualities and a position. | |
| From: report of Anthony Quinton (The Nature of Things [1973], Pt I) by Keith Campbell - The Metaphysic of Abstract Particulars §5 | |
| A reaction: This seems the obvious defence of a bundle account of objects against the charge that indiscernibles would have to be identical. It introduces, however, 'positions' into the ontology, but maybe that price must be paid. Materialism needs space. |
| 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. |
| 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. |
| 11214 | We learn 'not' along with affirmation, by learning to either affirm or deny a sentence [Rumfitt] |
| Full Idea: The standard view is that affirming not-A is more complex than affirming the atomic sentence A itself, with the latter determining its sense. But we could learn 'not' directly, by learning at once how to either affirm A or reject A. | |
| From: Ian Rumfitt ("Yes" and "No" [2000], IV) | |
| A reaction: [compressed] This seems fairly anti-Fregean in spirit, because it looks at the psychology of how we learn 'not' as a way of clarifying what we mean by it, rather than just looking at its logical behaviour (and thus giving it a secondary role). |