21 ideas
| 13985 | A true proposition seems true of one fact, but a false proposition seems true of nothing at all. [Ryle] |
| Full Idea: Whereas there might be just one fact that a true proposition was like, we would have to say that a false proposition was unlike any fact. We could not speak of the fact that it was false of, so we could not speak of its being false of anything at all. | |
| From: Gilbert Ryle (Are there propositions? [1930], 'Objections') | |
| A reaction: Ryle brings out very nicely the point Russell emphasised so much, that the most illuminating studies in philosophy are of how falsehood works, rather than of how truths work. If I say 'the Queen is really a man' it is obvious what that is false of. |
| 13984 | Two maps might correspond to one another, but they are only 'true' of the country they show [Ryle] |
| Full Idea: One map of Sussex is like another, but it is not true of that other map, but only of the county. | |
| From: Gilbert Ryle (Are there propositions? [1930], 'Objections') | |
| A reaction: One might question whether a map is in any sense 'true' of Sussex, though one must admit that there are good and bad maps of Sussex. The point is a nice one, which shows that there is no simple account of truth as correspondence. |
| 13979 | Logic studies consequence, compatibility, contradiction, corroboration, necessitation, grounding.... [Ryle] |
| Full Idea: Logic studies the way in which one thing follows from another, in which one thing is compatible with another, contradicts, corroborates or necessitates another, is a special case of another or the nerve of another. And so on. | |
| From: Gilbert Ryle (Are there propositions? [1930], IV) | |
| A reaction: I presume that 'and so on' would include how one thing proves another. This is quite a nice list, which makes me think a little more widely about the nature of logic (rather than just about inference). Incompatibility isn't a process. |
| 14187 | If logic is topic-neutral that means it delves into all subjects, rather than having a pure subject matter [Read] |
| Full Idea: The topic-neutrality of logic need not mean there is a pure subject matter for logic; rather, that the logician may need to go everywhere, into mathematics and even into metaphysics. | |
| From: Stephen Read (Formal and Material Consequence [1994], 'Logic') |
| 14188 | Not all arguments are valid because of form; validity is just true premises and false conclusion being impossible [Read] |
| Full Idea: Belief that every valid argument is valid in virtue of form is a myth. ..Validity is a question of the impossibility of true premises and false conclusion for whatever reason, and some arguments are materially valid and the reason is not purely logical. | |
| From: Stephen Read (Formal and Material Consequence [1994], 'Logic') | |
| A reaction: An example of a non-logical reason is the transitive nature of 'taller than'. Conceptual connections are the usual example, as in 'it's red so it is coloured'. This seems to be a defence of the priority of semantic consequence in logic. |
| 14182 | If the logic of 'taller of' rests just on meaning, then logic may be the study of merely formal consequence [Read] |
| Full Idea: In 'A is taller than B, and B is taller than C, so A is taller than C' this can been seen as a matter of meaning - it is part of the meaning of 'taller' that it is transitive, but not of logic. Logic is now seen as the study of formal consequence. | |
| From: Stephen Read (Formal and Material Consequence [1994], 'Reduct') | |
| A reaction: I think I find this approach quite appealing. Obviously you can reason about taller-than relations, by putting the concepts together like jigsaw pieces, but I tend to think of logic as something which is necessarily implementable on a machine. |
| 14183 | Maybe arguments are only valid when suppressed premises are all stated - but why? [Read] |
| Full Idea: Maybe some arguments are really only valid when a suppressed premise is made explicit, as when we say that 'taller than' is a transitive concept. ...But what is added by making the hidden premise explicit? It cannot alter the soundness of the argument. | |
| From: Stephen Read (Formal and Material Consequence [1994], 'Suppress') |
| 14184 | In modus ponens the 'if-then' premise contributes nothing if the conclusion follows anyway [Read] |
| Full Idea: A puzzle about modus ponens is that the major premise is either false or unnecessary: A, If A then B / so B. If the major premise is true, then B follows from A, so the major premise is redundant. So it is false or not needed, and contributes nothing. | |
| From: Stephen Read (Formal and Material Consequence [1994], 'Repres') | |
| A reaction: Not sure which is the 'major premise' here, but it seems to be saying that the 'if A then B' is redundant. If I say 'it's raining so the grass is wet', it seems pointless to slip in the middle the remark that rain implies wet grass. Good point. |
| 14186 | Logical connectives contain no information, but just record combination relations between facts [Read] |
| Full Idea: The logical connectives are useful for bundling information, that B follows from A, or that one of A or B is true. ..They import no information of their own, but serve to record combinations of other facts. | |
| From: Stephen Read (Formal and Material Consequence [1994], 'Repres') | |
| A reaction: Anyone who suggests a link between logic and 'facts' gets my vote, so this sounds a promising idea. However, logical truths have a high degree of generality, which seems somehow above the 'facts'. |
| 13988 | Many sentences do not state facts, but there are no facts which could not be stated [Ryle] |
| Full Idea: There are many sentences which do not state facts, while there are no facts which (in principle) could not be stated. | |
| From: Gilbert Ryle (Are there propositions? [1930], 'Substitute') | |
| A reaction: Hm. This seems like a nice challenge. The first problem would be infinite facts. Then complex universal facts, beyond the cognizance of any mind. Then facts that change faster than thinking can change. Do you give up yet? Then there's.... |
| 14185 | Conditionals are just a shorthand for some proof, leaving out the details [Read] |
| Full Idea: Truth enables us to carry various reports around under certain descriptions ('what Iain said') without all the bothersome detail. Similarly, conditionals enable us to transmit a record of proof without its detail. | |
| From: Stephen Read (Formal and Material Consequence [1994], 'Repres') | |
| A reaction: This is his proposed Redundancy Theory of conditionals. It grows out of the problem with Modus Ponens mentioned in Idea 14184. To say that there is always an implied 'proof' seems a large claim. |
| 13983 | Representation assumes you know the ideas, and the reality, and the relation between the two [Ryle] |
| Full Idea: The theory of Representative Ideas begs the whole question, by assuming a) that we can know these 'Ideas', b) that we can know the realities they represent, and c) we can know a particular 'idea' to be representative of a particular reality. | |
| From: Gilbert Ryle (Are there propositions? [1930], 'Objections') | |
| A reaction: Personally I regard the ideas as immediate (rather than acquired by some knowledge process), and I am dimly hoping that they represent reality (or I'm in deep trouble), and I am struggling to piece together the reality they represent. I'm happy with that. |
| 13980 | If you like judgments and reject propositions, what are the relata of incoherence in a judgment? [Ryle] |
| Full Idea: Those who find 'judgments' everywhere and propositions nowhere find that some judgments cohere whereas others are incoherent. What is the status of the terms between which these relations hold? | |
| From: Gilbert Ryle (Are there propositions? [1930], IV) | |
| A reaction: Ryle is playing devil's advocate, but this strikes me as a nice point. I presume Russell after 1906 is the sort of thinker he has in mind. |
| 13978 | Husserl and Meinong wanted objective Meanings and Propositions, as subject-matter for Logic [Ryle] |
| Full Idea: It is argued by Husserl and (virtually) by Meinong that only if there are such entities as objective Meanings - and propositions are just a species of Meaning - is there anything for Logic to be about. | |
| From: Gilbert Ryle (Are there propositions? [1930], IV) | |
| A reaction: It is presumably this proposal which led to the scepticism about meanings in Wittgenstein, Quine and Kripke. The modern view, which strikes me as right, is that logic is about inference, and so doesn't need a subject-matter. |
| 13977 | When I utter a sentence, listeners grasp both my meaning and my state of mind [Ryle] |
| Full Idea: If I have uttered my sentence aloud, a listener can both understand what I say or grasp my meaning, and also infer to my state of mind. | |
| From: Gilbert Ryle (Are there propositions? [1930], I) | |
| A reaction: This simple observations seems rather important. If we shake written words onto the floor, they might add up to a proper sentence, but half of the point of a sentence is missing. Irony trades on the gap between meaning and state of mind. |
| 13976 | 'Propositions' name what is thought, because 'thoughts' and 'judgments' are too ambiguous [Ryle] |
| Full Idea: As the orthodox terms 'thoughts' and 'judgments' are equivocal, since they may equally well denote 'thinkings' as 'what-is-thought', the 'accusatives' of acts of thinking have come to be called 'propositions'. | |
| From: Gilbert Ryle (Are there propositions? [1930], I) | |
| A reaction: I have understood propositions to be capable of truth or falsity. 'What is thought' could be a right old jumble of images and disjointed fragments. Propositions are famous for their unity! |
| 13981 | Several people can believe one thing, or make the same mistake, or share one delusion [Ryle] |
| Full Idea: We ordinarily find no difficulty in saying of a given thing that several people believe it and so, if they think it false, 'make the same mistake' or 'labour under the same delusion'. | |
| From: Gilbert Ryle (Are there propositions? [1930], IV) | |
| A reaction: Ryle is playing devil's advocate, but this (like 13980) strikes me as quite good support for propositions. I suppose you can describe these phenomena as assent to sentences, but they might be very different sentences to express the same delusion. |
| 13987 | We may think in French, but we don't know or believe in French [Ryle] |
| Full Idea: Although we speak of thinking in French, we never talk of knowing or believing or opining in French. | |
| From: Gilbert Ryle (Are there propositions? [1930], 'Substitute') | |
| A reaction: Once again Ryle is playing devil's advocate, but he does it rather well, and offers good support for my belief in propositions. I love this. 'I know, in French, a bank where the wild thyme blows'. |
| 13989 | There are no propositions; they are just sentences, used for thinking, which link to facts in a certain way [Ryle] |
| Full Idea: There are no substantial propositions...There is just a relation between grammatical structure and the logical structure of facts. 'Proposition' denotes the same as 'sentence' or 'statement'. A proposition is not what I think, but what I think or talk in. | |
| From: Gilbert Ryle (Are there propositions? [1930], 'Conclusions') | |
| A reaction: The conclusion of Ryle's discussion, but I found his support for propositions much more convincing than his critique of them, or his attempt at an alternative linguistic account. He never mentioned animals, so he self-evidently hasn't grasped the problem. |
| 13982 | If we accept true propositions, it is hard to reject false ones, and even nonsensical ones [Ryle] |
| Full Idea: All the arguments for the subsistence of true propositions seem to hold good for the subsistence of false ones. We might even have to find room for absurd or nonsensical ones like 'some round squares are not red-headed'. | |
| From: Gilbert Ryle (Are there propositions? [1930], 'Objections') | |
| A reaction: A particularly nice example of a Category Mistake from the man who made them famous. Why can't we just make belief a proposition attitude, so I equally believe 'sea is blue', 'grass is pink' and 'trees are bifocal', but the status of my belief varies? |
| 23688 | Noncognitivism tries to avoid both naturalism and mysterious morality [Hacker-Wright] |
| Full Idea: Noncognitivism is an attempt to avoid the alleged problems of naturalism without the mysteries of Moore's non-naturalism. | |
| From: John Hacker-Wright (Philippa Foot's Moral Thought [2013], 1) | |
| A reaction: R.M. Hare is the best example of this approach. Moore's Open Question argument was said to prove the Naturalistic Fallacy, which imagined that morality could be a feature of nature. It led Moore to platonism. I prefer Philippa Foot. |