6 ideas
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. |
6410 | The only real proper names are 'this' and 'that'; the rest are really definite descriptions. [Russell, by Grayling] |
Full Idea: Russell argued that the only 'logically proper' names are those which denote particular entities with which one can be acquainted. The best examples are 'this' and 'that'; other apparent names turn out, when analysed, to be definite descriptions. | |
From: report of Bertrand Russell (On the Nature of Acquaintance [1914]) by A.C. Grayling - Russell Ch.2 | |
A reaction: This view is firm countered by the causal theory of reference, proposed by Kripke and others, in which not only people like Aristotle are 'baptised' with a name, but also natural kinds such as water. It is hard to disagree with Kripke on this. |
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). |
22269 | We must fight fiercely to hang on to the few pleasures which survive into old age [Montaigne] |
Full Idea: I am training and sharpening my appetite for those pleasures that are left. ...We must cling tooth and claw to the use of the pleasures of this life which the advancing years, one after another, rip from our grasp. | |
From: Michel de Montaigne (I.39 On Solitude [1580], p.276) | |
A reaction: That may be one of the most inspiring ideas I have read about pleasure. |