7 ideas
| 16252 | Metaphysics uses empty words, or just produces pseudo-statements [Carnap] |
| Full Idea: Since metaphysics doesn't want to assert analytic propositions, nor fall within the domain of physical science, it is compelled to employ words for which no criteria of application are specified, ..or else combine meaningful words..into pseudo-statements. | |
| From: Rudolph Carnap (Elimination of Metaphysics by Analysis of Language [1959]), quoted by Tim Maudlin - The Metaphysics within Physics 2.4 | |
| A reaction: A classic summary of the logical positivist rejection of metaphysics. I incline to treat metaphysics as within the domain of science, but at a level of generality so high that practising scientists become bewildered and give up. |
| 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. |
| 4988 | Folk psychology may not be reducible, but that doesn't make it false [Kirk,R on Churchland,PM] |
| Full Idea: It may well be that completed neuroscience will not include a reduction of folk psychology, but why should that be a reason to regard it as false? It would only be a reason if irreducibility entailed that they could not possibly both be true. | |
| From: comment on Paul M. Churchland (Eliminative Materialism and Prop. Attitudes [1981]) by Robert Kirk - Mind and Body §3.9 | |
| A reaction: If all our behaviour had been explained by a future neuro-science, this might not falsify folk psychology, but it would totally marginalise it. It is still possible that dewdrops are placed on leaves by fairies, but this is no longer a hot theory. |
| 4987 | Eliminative materialism says folk psychology will be replaced, not reduced [Churchland,PM] |
| Full Idea: Eliminative materialism says our common-sense conception of psychological phenomena is a radically false theory, so defective that both the principles and the ontology of that theory will eventually be displaced (rather than reduced). | |
| From: Paul M. Churchland (Eliminative Materialism and Prop. Attitudes [1981], Intro) | |
| A reaction: It is hard to see what you could replace the idea of a 'belief' with in ordinary conversation. We may reduce beliefs to neuronal phenomena, but we can't drop the vocabulary of the macro-phenomena. The physics of weather doesn't eliminate 'storms'. |
| 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). |