12 ideas
| 23449 | Interpreting a text is representing it as making sense [Morris,M] |
| Full Idea: Interpreting a text is a matter of making sense of it. And to make sense of a text is to represent it as making sense. | |
| From: Michael Morris (Guidebook to Wittgenstein's Tractatus [2008], Intro.2) | |
| A reaction: 'Making sense' is obviously not a very precise or determinate concept. It is probably better to say that the process is 'trying' to make sense of the text, because most texts don't totally make sense. |
| 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. |
| 23484 | Bipolarity adds to Bivalence the capacity for both truth values [Morris,M] |
| Full Idea: According to the Principle of Bipolarity, every meaningful sentence must be capable both of being true and of being false. It is not enough merely that every sentence must be either true or false (which is Bivalence). | |
| From: Michael Morris (Guidebook to Wittgenstein's Tractatus [2008], 3D) | |
| A reaction: It is said that early Wittgenstein endorses this. That is, in addition to being true, the sentence must be capable of falsehood (and vice versa). This seems to be flirting with the verification principle. I presume it is 'affirmative' sentences. |
| 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. |
| 23494 | Conjunctive and disjunctive quantifiers are too specific, and are confined to the finite [Morris,M] |
| Full Idea: There are two problems with defining the quantifiers in terms of conjunction and disjunction. The general statements are unspecific, and do not say which things have the properties, and also they can't range over infinite objects. | |
| From: Michael Morris (Guidebook to Wittgenstein's Tractatus [2008], 5C) | |
| A reaction: That is, the universal quantifier is lots of ands, and the existential is lots of ors. If there only existed finite objects, then naming them all would be universal, and the infinite wouldn't be needed. |
| 23451 | Counting needs to distinguish things, and also needs the concept of a successor in a series [Morris,M] |
| Full Idea: Just distinguishing things is not enough for counting (and hence arithmetic). We need the crucial extra notion of the successor in a series of some kind. | |
| From: Michael Morris (Guidebook to Wittgenstein's Tractatus [2008], Intro.5) | |
| A reaction: This is a step towards the Peano Axioms of arithmetic. The successors could be fingers and toes, taken in a conventional order, and matched one-to-one to the objects. 'My right big toe of cows' means 16 cows (but non-verbally). |
| 23460 | To count, we must distinguish things, and have a series with successors in it [Morris,M] |
| Full Idea: Distinguishing between things is not enough for counting. …We need the crucial extra notion of a successor in a series of a certain kind. | |
| From: Michael Morris (Guidebook to Wittgenstein's Tractatus [2008], Intro) | |
| A reaction: This is the thinking that led to the Dedekind-Peano axioms for arithmetic. E.g. each series member can only have one successor. There is an unformalisable assumption that the series can then be applied to the things. |
| 23452 | Discriminating things for counting implies concepts of identity and distinctness [Morris,M] |
| Full Idea: The discrimination of things for counting needs to bring with it the notion of identity (and, correlatively, distinctness). | |
| From: Michael Morris (Guidebook to Wittgenstein's Tractatus [2008], Intro.5) | |
| A reaction: Morris is exploring how practices like counting might reveal necessary truths about the world. |
| 6386 | In no important way can psychology be reduced to the physical sciences [Davidson] |
| Full Idea: There is no important sense in which psychology can be reduced to the physical sciences. | |
| From: Donald Davidson (The Material Mind [1973], p.259) | |
| A reaction: In no 'important' way can the beauty of the Lake District be reduced to geology - but it is geology. 'Important' to whom? To a metaphysician, I would say psychology does reduce to physics, and that is important, but it is not important to a psychologist. |
| 23491 | There must exist a general form of propositions, which are predictabe. It is: such and such is the case [Morris,M] |
| Full Idea: The existence of a general propositional form is proved by the fact that there cannot be a proposition whose form could not have been foreseen (i.e. constructed). The general form of the proposition is: Such and such is the case. | |
| From: Michael Morris (Guidebook to Wittgenstein's Tractatus [2008], 4.5) | |
| A reaction: [last bit in Ogden translation] LW eventually expresses this symbolically. We could just say a proposition is an assertion. This strikes as either a rather empty claim, or an unfounded one. |
| 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). |