8 ideas
21552 | Common speech is vague; its vocabulary and syntax must be modified, for precision [Russell] |
Full Idea: I am persuaded that common speech is full of vagueness and inaccuracy, and that any attempt to be precise and accurate requires modification of common speech both as regards vocabulary and as regards syntax. | |
From: Bertrand Russell (Mr Strawson on Referring [1957], p.123) | |
A reaction: It is interesting that he cites the syntax of ordinary language, as well as the vocabulary. The implication is that vagueness can also be a feature of syntax (and hence his pursuit of logical form), which is not normally mentioned |
21551 | Empirical words need ostensive definition, which makes them egocentric [Russell] |
Full Idea: The meanings of all empirical words depend ultimately upon ostensive definitions, ostensive definitions depend upon experience, and that experience is egocentric. | |
From: Bertrand Russell (Mr Strawson on Referring [1957], p.122) | |
A reaction: He seems to imply that this makes them partly subjective, but I don't see why an objective consensus can't be reached when making an ostensive definition. We just need to clearly agree what 'that' refers to. |
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. |
17699 | Variables are auxiliary notions, and not part of the 'eternal' essence of logic [Schönfinkel] |
Full Idea: A variable in a proposition of logic ....has the status of a mere auxiliary notion that is really inappropriate to the constant, 'eternal' essence of the propositions of logic. | |
From: Moses Schönfinkel (Building Blocks of Mathematical Logic [1924], §1) | |
A reaction: He presumably thinks that what the variables stand for (and he mentions 'argument places' and 'operators') will be included in the essence. My attention was caught by the thought that he takes logic to have an essence. |
21550 | Science reduces indexicals to a minimum, but they can never be eliminated from empirical matters [Russell] |
Full Idea: It is of the essence of a scientific account of the world to reduce to a minimum the egocentric element in assertion, but success in this attempt is a matter of degree, and is never complete where empirical matter is concerned. | |
From: Bertrand Russell (Mr Strawson on Referring [1957], p.121) | |
A reaction: He cites ostensive definitions. The key issue is whether they can be wholly eliminated when we try to be objective. Russell here endorses Perry's claim that they never go away. Personally I just think that (if so) we should try harder. |
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). |