8 ideas
| 21697 | The Struthionic Fallacy is that of burying one's head in the sand [Quine] |
| Full Idea: The Struthionic Fallacy is that of burying one's head in the sand [which I name from the Greek for 'ostrich'] | |
| From: Willard Quine (Lecture on Nominalism [1946], §4) | |
| A reaction: David Armstrong said this is the the fallacy involved in a denial of universals. Quine is accusing Carnap and co. of the fallacy. |
| 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. |
| 21698 | All relations, apart from ancestrals, can be reduced to simpler logic [Quine] |
| Full Idea: Much of the theory of relations can be developed as a virtual theory, in which we seem to talk of relations, but can explain our notation in terms {finally] of just the logic of truth-functions, quantification and identity. The exception is ancestrals. | |
| From: Willard Quine (Lecture on Nominalism [1946], §8) | |
| A reaction: The irreducibility of ancestrals is offered as a reason for treating sets as universals. |
| 21696 | Nominalism rejects both attributes and classes (where extensionalism accepts the classes) [Quine] |
| Full Idea: 'Nominalism' is distinct from 'extensionalism'. The main point of the latter doctrine is rejection of properties or attributes in favour of classes. But class are universals equally with attributes, and nominalism in the defined sense rejects both. | |
| From: Willard Quine (Lecture on Nominalism [1946], §3) | |
| A reaction: Hence Quine soon settled on labelling himself as an 'extensionalist', leaving proper nominalism to Nelson Goodman. It is commonly observed that science massively refers to attributes, so they can't just be eliminated. |
| 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). |
| 18555 | The beautiful is that from which nothing can be subtracted and to which nothing can be added [Alberti] |
| Full Idea: The beautiful is that from which nothing can be taken away and to which nothing can be added but for the worse. | |
| From: Leon Battista Alberti (De Re Aedificatoria [1485]), quoted by Roger Scruton - Beauty: a very short introduction 9 | |
| A reaction: Scruton rejects this Platonic tradition of beauty as organic wholeness, because you can't say how it would be 'worse' without invoking beauty, which makes it circular. Scruton appears to be correct. |