8 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. |
| 17447 | Parsons says counting is tagging as first, second, third..., and converting the last to a cardinal [Parsons,C, by Heck] |
| Full Idea: In Parsons's demonstrative model of counting, '1' means the first, and counting says 'the first, the second, the third', where one is supposed to 'tag' each object exactly once, and report how many by converting the last ordinal into a cardinal. | |
| From: report of Charles Parsons (Frege's Theory of Numbers [1965]) by Richard G. Heck - Cardinality, Counting and Equinumerosity 3 | |
| A reaction: This sounds good. Counting seems to rely on that fact that numbers can be both ordinals and cardinals. You don't 'convert' at the end, though, because all the way you mean 'this cardinality in this order'. |
| 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). |
| 23035 | The good life aims at perfections, or absolute laws, or what is absolutely desirable [Green,TH] |
| Full Idea: The differentia of the good life …is controlled by the consciousness of there being some perfection which has to be fulfilled, some law which has to be obeyed, something absolutely desirable whatever the individual may for the time desire. | |
| From: T.H. Green (Prolegomena to Ethics [1882], p.134), quoted by John H. Muirhead - The Service of the State II | |
| A reaction: The 'perfection' suggests Plato, and the 'law' suggests Kant. The idea that something is 'absolutely desirable' is, I suspect, aimed at the utilitarians, who don't care what is desired. I'm no idealist, but have some sympathy with this idea. |
| 23037 | People are improved by egalitarian institutions and habits [Green,TH] |
| Full Idea: Man has bettered himself through institutions and habits which tend to make the welfare of all the welfare of each. | |
| From: T.H. Green (Prolegomena to Ethics [1882], p.180), quoted by John H. Muirhead - The Service of the State II | |
| A reaction: I like this a lot. We underestimate how the best social values are promoted by the existence of enlightened institutions, rather than by preaching and teaching. Schools, law courts and churche embody their values. |
| 23043 | All talk of the progress of a nation must reduce to the progress of its individual members [Green,TH] |
| Full Idea: Our ultimate standard of worth is an ideal of personal worth. All other values are relative to personal values. To speak of any progress of a nation or society or mankind except as relative to some greater worth of persons is to use words without meaning. | |
| From: T.H. Green (Prolegomena to Ethics [1882], p.193), quoted by John H. Muirhead - The Service of the State II | |
| A reaction: Note that, pre-verificationism, a Victorian talks of plausible words actually being meaningless. This is a good statement of the core doctrine of liberalism. |