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. |
| 4001 | The meaning of a word contains all its possible uses as well as its actual ones [Nagel] |
| Full Idea: The meaning of a word contains all its possible uses, true and false, not only its actual ones. | |
| From: Thomas Nagel (What Does It All Mean? [1987], Ch.5) | |
| A reaction: It has always seemed to me that meaning is not use, because you can't use it if it hasn't already got a meaning. What use is a meaningless word? |
| 20959 | Concepts are only analytic once the predicate is absorbed into the subject [Schleiermacher] |
| Full Idea: The difference between analytic and synthetic judgements is an unimportant fluid one. 'Ice melts' is analytic if it is already taken up into the concept of ice, and synthetic if not yet taken up. It is just a different state of the formation of concepts. | |
| From: Friedrich Schleiermacher (Dialektik [1833], p.563), quoted by Andrew Bowie - Introduction to German Philosophy 8 'Scientific' | |
| A reaction: [compressed] I wonder if Quine ever encountered this quotation. The idea refers to Kant's notion of analyticity, and makes the good point that predicates only become 'contained in the subject' once the situation is very familiar. |
| 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). |