21 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. |
8195 | Undecidable statements result from quantifying over infinites, subjunctive conditionals, and the past tense [Dummett] |
Full Idea: I once wrote that there are three linguistic devices that make it possible for us to frame undecidable statements: quantification over infinity totalities, as expressed by word such as 'never'; the subjunctive conditional form; and the past tense. | |
From: Michael Dummett (Truth and the Past [2001], 4) | |
A reaction: Dummett now repudiates the third one. Statements containing vague concepts also appear to be undecidable. Personally I have no problems with deciding (to a fair extent) about 'never x', and 'if x were true', and 'it was x'. |
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. |
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. |
8194 | Surely there is no exact single grain that brings a heap into existence [Dummett] |
Full Idea: There is surely no number n such that "n grains of sand do not make a heap, although n+1 grains of sand do" is true. | |
From: Michael Dummett (Truth and the Past [2001], 4) | |
A reaction: It might be argued that there is such a number, but no human being is capable of determing it. Might God know the value of n? On the whole Dummett's view seems the most plausible. |
8190 | Intuitionists rely on the proof of mathematical statements, not their truth [Dummett] |
Full Idea: The intuitionist account of the meaning of mathematical statements does not employ the notion of a statement's being true, but only that of something's being a proof of the statement. | |
From: Michael Dummett (Truth and the Past [2001], 2) | |
A reaction: I remain unconvinced that anyone could give an account of proof that didn't discreetly employ the notion of truth. What are we to make of "we suspect this is true, but no one knows how to prove it?" (e.g. Goldbach's Conjecture). |
8198 | A 'Cambridge Change' is like saying 'the landscape changes as you travel east' [Dummett] |
Full Idea: The idea of 'Cambridge Change' is like saying 'the landscape changes as you travel east'. | |
From: Michael Dummett (Truth and the Past [2001], 5) | |
A reaction: The phrase was coined in Oxford. It is a useful label with which realists can insult solipsists, idealists and other riff-raff. Four Dimensionalists seem to see time in this way. Events sit there, and we travel past them. But there are indexical events. |
8192 | I no longer think what a statement about the past says is just what can justify it [Dummett] |
Full Idea: In distinguishing between what can establish a statement about the past as true and what it is that that statement says, we are repudiating antirealism about the past. | |
From: Michael Dummett (Truth and the Past [2001], 3) | |
A reaction: This is a late shift of ground from the champion of antirealism. If Dummett's whole position is based on a 'justificationist' theory of meaning, he must surely have a different theory of meaning now for statements about the past? |
8199 | The existence of a universe without sentience or intelligence is an unintelligible fantasy [Dummett] |
Full Idea: The existence of a universe from which sentience was permanently absent is an unintelligible fantasy. What exists is what can be known to exist. What is true is what can be known to be true. Reality is what can be experienced and known. | |
From: Michael Dummett (Truth and the Past [2001], 5) | |
A reaction: This strikes me as nonsense. The fact that we cannot think about a universe without introducing a viewpoint does not mean that we cannot 'intellectually imagine' its existence devoid of viewpoints. Nothing could ever experience a star's interior. |
8193 | Verification is not an individual but a collective activity [Dummett] |
Full Idea: Verification is not an individual but a collective activity. | |
From: Michael Dummett (Truth and the Past [2001], 3) | |
A reaction: This generates problems. Are deceased members of the community included? (Yes, says Dummett). If someone speaks to angels (Blake!), do they get included? Is a majority necessary? What of weird loners? Etc. |
8189 | Truth-condition theorists must argue use can only be described by appeal to conditions of truth [Dummett] |
Full Idea: To demonstrate the necessity of a truth-conditional theory of meaning, a proponent of such a theory must argue that use cannot be described without appeal to the conditions for the truth of statements. | |
From: Michael Dummett (Truth and the Past [2001], 1) | |
A reaction: Unlike Dummett, I find that argument rather appealing. How do you decide the possible or appropriate use for a piece of language, if you don't already know what it means. Basing it all on social conventions means it could be meaningless ritual. |
8191 | The truth-conditions theory must get agreement on a conception of truth [Dummett] |
Full Idea: It is not enough for the truth-condition theorist to argue that we need the concept of truth: he must show that we should have the same conception of truth that he has. | |
From: Michael Dummett (Truth and the Past [2001], 2) | |
A reaction: Davidson invites us to accept Tarski's account of truth. It invites the question of what the theory would be like with a very robust correspondence account of truth, or a flabby rather subjective coherence view, or the worst sort of pragmatic view. |
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). |
23146 | Motives produce intentions, which lead to actions [Driver] |
Full Idea: Motives will cause persons for form intentions; it is intentions which more directly guide actions. | |
From: Julia Driver (The Virtues and Human Nature [1996], 3) | |
A reaction: This is invites the question of whether there is a sharp distinction between the motive and the action. Detectives look for motives, but law courts look for intentions. |
23147 | Good intentions are not necessary for virtue [Driver] |
Full Idea: I deny the claim that good intentions are necessary for virtue. | |
From: Julia Driver (The Virtues and Human Nature [1996], 3) | |
A reaction: Presumably one could continually do the right thing, because it was your duty or your job, without actually being well motivated for it. |
23144 | Virtue should be defined by consequences, not by states of mind [Driver] |
Full Idea: The behavioural aspects of virtue are more important than its phenomenology, because virtue is best defined along consequentialist lines. | |
From: Julia Driver (The Virtues and Human Nature [1996], Intro) | |
A reaction: This is the thesis of her paper. Quite persuasive. Consequences are, of course, important in all moral theories (even Kant's). She doesn't rely on human nature. The social virtues vary according to the circumstances, such as gossiping in wartime. |
23148 | Virtues are character traits or dispositions which produce good consequences for others [Driver] |
Full Idea: A moral virtue is a character trait (a disposition or cluster of dispositions) which, generally speaking, produces good consequences for others. | |
From: Julia Driver (The Virtues and Human Nature [1996], 3) | |
A reaction: There are self-directed virtues, such as keeping fit and healthy. There are virtues for ways to receive the kindness of others. That said, I like this idea. |
23150 | Control of pregnancy and knowledge of paternity have downgraded chastity [Driver] |
Full Idea: Women now have more control over becoming pregnant. Men can now be more certain of paternity, without the constraint of female chastity. Hence chastity is no longer considered a moral virtue. | |
From: Julia Driver (The Virtues and Human Nature [1996], 5) | |
A reaction: A persuasive argument that virtues are defined by their consequences (to which I add my example of gossiping in wartime). Different social situations and crises promote or relegate the status of certain virtues (such as food hoarding). |
23149 | If generosity systematically turned recipients into parasites, it wouldn't be a virtue [Driver] |
Full Idea: If generosity towards the needy in the long run produced [social] parasites, and if generosity did this systematically, then it would not be a moral virtue. | |
From: Julia Driver (The Virtues and Human Nature [1996], 5) | |
A reaction: A very persuasive example. Hume has similar views - that we encourage those emotions which have good social outcomes. |
8197 | Maybe past (which affects us) and future (which we can affect) are both real [Dummett] |
Full Idea: Maybe both the past and the future are real, determined by our current temporal perspective. Past is then events capable of having a causal influence upon events near us, and future is events we can affect, but from which we receive no information. | |
From: Michael Dummett (Truth and the Past [2001], 5) | |
A reaction: This is the Four-Dimensional view, which is opposed to Presentism. Might immediate unease is that it gives encouragement to fortune-tellers, whom I have always dismissed with 'You can't see the future, because it doesn't exist'. |
8196 | The present cannot exist alone as a mere boundary; past and future truths are rendered meaningless [Dummett] |
Full Idea: The idea that only the present is real cannot be sustained. St Augustine pointed out that the present has no duration; it is a mere boundary between past and future, and dependent on them. It also denies truth-value to statements about past or future. | |
From: Michael Dummett (Truth and the Past [2001], 5) | |
A reaction: To defend Presentism, I suspect that one must focus entirely on the activities of consciousness and short-term memory. All truths, of past or future, must refer totally to such mental events. But what could an event be if there is no enduring time? |