15 ideas
7085 | The main problem of philosophy is what can and cannot be thought and expressed [Wittgenstein, by Grayling] |
Full Idea: The 'Tractatus' concerns the theory of what can be expressed by propositions (and, which comes to the same thing, can be thought), and what cannot be expressed by propositions, but can only be shown; which, I believe, is the main problem of philosophy. | |
From: report of Ludwig Wittgenstein (Letters to Russell [1919]) by A.C. Grayling - Wittgenstein Ch.2 | |
A reaction: This contains what a I consider the heresy of making thought depend on language, but his main question remains, of the limits of thought. It is dramatised nicely in the 'mysterian' view of the mind-body problem (e.g. Idea 2540). |
9123 | Someone standing in a doorway seems to be both in and not-in the room [Priest,G, by Sorensen] |
Full Idea: Priest says there is room for contradictions. He gives the example of someone in a doorway; is he in or out of the room. Given that in and out are mutually exclusive and exhaustive, and neither is the default, he seems to be both in and not in. | |
From: report of Graham Priest (What is so bad about Contradictions? [1998]) by Roy Sorensen - Vagueness and Contradiction 4.3 | |
A reaction: Priest is a clever lad, but I don't think I can go with this. It just seems to be an equivocation on the word 'in' when applied to rooms. First tell me the criteria for being 'in' a room. What is the proposition expressed in 'he is in the room'? |
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'. |
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. |
23463 | Atomic facts correspond to true elementary propositions [Wittgenstein] |
Full Idea: Atomic fact [Sachverhalt] is what corresponds to an elementary proposition [Elementarsatz] if it is true. | |
From: Ludwig Wittgenstein (Letters to Russell [1919], CL 125) | |
A reaction: This is perhaps the key to the Tractatus, because it is the binding point between world and language. A true realist would allow for atomic facts that may go beyond even possible propositions. |
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. |
23490 | A thought is mental constituents that relate to reality as words do [Wittgenstein] |
Full Idea: Does a Gedanke [thought] consist of words? No! But of psychical constituents that have the same sort of relation to reality as words. | |
From: Ludwig Wittgenstein (Letters to Russell [1919], p.125), quoted by Michael Morris - Guidebook to Wittgenstein's Tractatus 4B | |
A reaction: This is roughly my view of propositions, as non-lingustic mental events. The 'psychical constituents' seem to be concepts, in a psychological rather than a Fregean sense. This idea allowed transfer of his representation theory from thought to language. |
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? |