34 ideas
23367 | Even pointing a finger should only be done for a reason [Epictetus] |
Full Idea: Philosophy says it is not right even to stretch out a finger without some reason. | |
From: Epictetus (fragments/reports [c.57], 15) | |
A reaction: The key point here is that philosophy concerns action, an idea on which Epictetus is very keen. He rather despise theory. This idea perfectly sums up the concept of the wholly rational life (which no rational person would actually want to live!). |
6420 | Only by analysing is progress possible in philosophy [Russell] |
Full Idea: I remain firmly persuaded, in spite of some modern tendencies to the contrary, that only by analysing is progress possible, …for example, by analysing physics and perception, the problem of mind and matter can be completely solved. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.1) | |
A reaction: I don't share his confidence in the second part of this, but I subscribe to the maxim that 'analsis is the path to wisdom'. It is a very western view, and lots of people (mostly of a mystical disposition) hate it, but I see no better path. |
6432 | Analysis gives new knowledge, without destroying what we already have [Russell] |
Full Idea: It seems to me evident that, as in the case of impure water, analysis gives new knowledge without destroying any of the previously existing knowledge. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.11) | |
A reaction: I agree. On the whole, opponents of analysis are sentimental mystics who are reluctant to think carefully about life. I'm not sure what careful and concentrated thought is capable of, apart from analysis. |
8996 | If if time is money then if time is not money then time is money then if if if time is not money... [Quine] |
Full Idea: If if time is money then if time is not money then time is money then if if if time is not money then time is money then time is money then if time is money then time is money. | |
From: Willard Quine (Truth by Convention [1935], p.95) | |
A reaction: Quine offers this with no hint of a smile. I reproduce it for the benefit of people who hate analytic philosophy, and get tired of continental philosophy being attacked for its obscurity. |
8995 | Definition by words is determinate but relative; fixing contexts could make it absolute [Quine] |
Full Idea: A definition endows a word with complete determinacy of meaning relative to other words. But we could determine the meaning of a new word absolutely by specifying contexts which are to be true and contexts which are to be false. | |
From: Willard Quine (Truth by Convention [1935], p.89) | |
A reaction: This is the beginning of Quine's distinction between the interior of 'the web' and its edges. The attack on the analytic/synthetic distinction will break down the boundary between the two. Surprising to find 'absolute' anywhere in Quine. |
6437 | The theory of types makes 'Socrates and killing are two' illegitimate [Russell] |
Full Idea: 'Socrates and killing are two' would be an illegitimate sentence according to the doctrine of types. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.14) | |
A reaction: This nicely shows how Ryle's notion of a 'category mistake', although it is a commonsense observation of bogus reasoning, arises out of Russell's logical analysis of sets. Of course, the theory of types has its critics. |
6442 | Truth belongs to beliefs, not to propositions and sentences [Russell] |
Full Idea: Truth and falsehood both belong primarily to beliefs, and only derivatively to propositions and sentences. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.15) | |
A reaction: I'm not sure why a proposition which is date/place stamped ('it is raining, here and now') could not be considered a truth, even if no one believed it. Is not the proposition 'squares have four sides' true? |
6436 | I gradually replaced classes with properties, and they ended as a symbolic convenience [Russell] |
Full Idea: My original use of classes was gradually more and more replaced by properties, and in the end disappeared except as a symbolic convenience. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.14) | |
A reaction: I wish I knew what properties are. On the whole, though, I agree with this, because it is more naturalistic. We may place things in classes because of their properties, and this means there are natural classes, but classes can't have a life of their own. |
10064 | Quine quickly dismisses If-thenism [Quine, by Musgrave] |
Full Idea: Quine quickly dismisses If-thenism. | |
From: report of Willard Quine (Truth by Convention [1935], p.327) by Alan Musgrave - Logicism Revisited §5 | |
A reaction: [Musgrave quotes a long chunk of Quine which is hard to compress!] Effectively, he says If-thenism is cheating, or begs the question, by eliminating whole sections of perfectly good mathematics, because they cannot be derived from axioms. |
20296 | Logic needs general conventions, but that needs logic to apply them to individual cases [Quine, by Rey] |
Full Idea: Quine argues that logic could not be established by conventions, since the logical truths, being infinite in number, must be given by general conventions rather than singly; and logic is needed in the meta-theory, to apply to individual cases. | |
From: report of Willard Quine (Truth by Convention [1935]) by Georges Rey - The Analytic/Synthetic Distinction 3.4 | |
A reaction: A helpful insight into Quine's claim. If only someone would print these one sentence summaries at the top of classic papers, we would all get far more out of them at first reading. Assuming Rey is right! |
8998 | Claims that logic and mathematics are conventional are either empty, uninteresting, or false [Quine] |
Full Idea: If logic and mathematics being true by convention says the primitives can be conventionally described, that works for anything, and is empty; if the conventions are only for those fields, that's uninteresting; if a general practice, that is false. | |
From: Willard Quine (Truth by Convention [1935], p.102) | |
A reaction: This is Quine's famous denial of the traditional platonist view, and the new Wittgensteinian conventional view, preparing the ground for a more naturalistic and empirical view. I feel more sympathy with Quine than with the other two. |
8999 | Logic isn't conventional, because logic is needed to infer logic from conventions [Quine] |
Full Idea: If logic is to proceed mediately from conventions, logic is needed for inferring logic from the conventions. Conventions for adopting logical primitives can only be communicated by free use of those very idioms. | |
From: Willard Quine (Truth by Convention [1935], p.104) | |
A reaction: A common pattern of modern argument, which always seems to imply that nothing can ever get off the ground. I suspect that there are far more benign circles in the world of thought than most philosophers imagine. |
9000 | If a convention cannot be communicated until after its adoption, what is its role? [Quine] |
Full Idea: When a convention is incapable of being communicated until after its adoption, its role is not clear. | |
From: Willard Quine (Truth by Convention [1935], p.106) | |
A reaction: Quine is discussing the basis of logic, but the point applies to morality - that if there is said to be a convention at work, the concepts of morality must already exist to get the conventional framework off the ground. What is it that comes first? |
7528 | Leibniz bases everything on subject/predicate and substance/property propositions [Russell] |
Full Idea: The metaphysics of Leibniz was explicitly based upon the doctrine that every proposition attributes a predicate to a subject and (what seemed to him almost the same thing) that every fact consists of a substance having a property. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.5) | |
A reaction: I think it is realised now that although predicates tend to attribute properties to things, they are far from being the same thing. See Idea 4587, for example. Russell gives us an interesting foot in the door of Leibniz's complex system. |
6439 | Names are meaningless unless there is an object which they designate [Russell] |
Full Idea: Unlike descriptions, names are meaningless unless there is an object which they designate. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.14) | |
A reaction: This interests Russell because of its ontological implications. If we reduce language to names, we can have a pure ontology of 'objects'. We need a system for saying whether a description names something - which is his theory of definite descriptions. |
8994 | If analytic geometry identifies figures with arithmetical relations, logicism can include geometry [Quine] |
Full Idea: Geometry can be brought into line with logicism simply by identifying figures with arithmetical relations with which they are correlated thought analytic geometry. | |
From: Willard Quine (Truth by Convention [1935], p.87) | |
A reaction: Geometry was effectively reduced to arithmetic by Descartes and Fermat, so this seems right. You wonder, though, whether something isn't missing if you treat geometry as a set of equations. There is more on the screen than what's in the software. |
8997 | There are four different possible conventional accounts of geometry [Quine] |
Full Idea: We can construe geometry by 1) identifying it with algebra, which is then defined on the basis of logic; 2) treating it as hypothetical statements; 3) defining it contextually; or 4) making it true by fiat, without making it part of logic. | |
From: Willard Quine (Truth by Convention [1935], p.99) | |
A reaction: [Very compressed] I'm not sure how different 3 is from 2. These are all ways to treat geometry conventionally. You could be more traditional, and say that it is a description of actual space, but the multitude of modern geometries seems against this. |
6423 | We tried to define all of pure maths using logical premisses and concepts [Russell] |
Full Idea: The primary aim of our 'Principia Mathematica' was to show that all pure mathematics follows from purely logical premisses and uses only concepts definable in logical terms. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.7) | |
A reaction: This spells out the main programme of logicism, by its great hero, Russell. The big question now is whether Gödel's Incompleteness Theorems have succeeded in disproving logicism. |
8993 | If mathematics follows from definitions, then it is conventional, and part of logic [Quine] |
Full Idea: To claim that mathematical truths are conventional in the sense of following logically from definitions is the claim that mathematics is a part of logic. | |
From: Willard Quine (Truth by Convention [1935], p.79) | |
A reaction: Quine is about to attack logic as convention, so he is endorsing the logicist programme (despite his awareness of Gödel), but resisting the full Wittgenstein conventionalist picture. |
6424 | Formalists say maths is merely conventional marks on paper, like the arbitrary rules of chess [Russell] |
Full Idea: The Formalists, led by Hilbert, maintain that arithmetic symbols are merely marks on paper, devoid of meaning, and that arithmetic consists of certain arbitrary rules, like the rules of chess, by which these marks can be manipulated. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.10) | |
A reaction: I just don't believe that maths is arbitrary, and this view pushes me into the arms of the empiricists, who say maths is far more likely to arise from experience than from arbitrary convention. The key to maths is patterns. |
6425 | Formalism can't apply numbers to reality, so it is an evasion [Russell] |
Full Idea: Formalism is perfectly adequate for doing sums, but not for the application of number, such as the simple statement 'there are three men in this room', so it must be regarded as an unsatisfactory evasion. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.10) | |
A reaction: This seems to me a powerful and simple objection. The foundation of arithmetic is that there are three men in the room, not that one plus two is three. Three men and three ties make a pattern, which we call 'three'. |
6426 | Intuitionism says propositions are only true or false if there is a method of showing it [Russell] |
Full Idea: The nerve of the Intuitionist theory, led by Brouwer, is the denial of the law of excluded middle; it holds that a proposition can only be accounted true or false when there is some method of ascertaining which of these it is. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.2) | |
A reaction: He cites 'there are three successive sevens in the expansion of pi' as a case in point. This seems to me an example of the verificationism and anti-realism which is typical of that period. It strikes me as nonsense, but Russell takes it seriously. |
6419 | In 1899-1900 I adopted the philosophy of logical atomism [Russell] |
Full Idea: In the years 1899-1900 I adopted the philosophy of logical atomism. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.1) | |
A reaction: This is interesting (about Russell) because he only labelled it as 'logical atomism' in about 1912, and only wrote about it as such in 1918. It is helpful to understand that the theory of definite descriptions was part of his logical atomism. |
6438 | Complex things can be known, but not simple things [Russell] |
Full Idea: I have come to think that, although many things can be known to be complex, nothing can be known to be simple. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.14) | |
A reaction: This appears to be a rejection of his logical atomism. It goes with a general rebellion against foundationalist epistemology, because the empiricists foundations (e.g. Hume's impressions) seem devoid of all content. |
6434 | Facts are everything, except simples; they are either relations or qualities [Russell] |
Full Idea: Facts, as I am using the word, consist always of relations between parts of a whole or qualities of single things; facts, in a word, are whatever there is except what (if anything) is completely simple. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.13) | |
A reaction: This is the view that goes with Russell's 'logical atomism', where the 'completely simple' is used to build up the 'facts'. If World War One was a fact, was it a 'relation' or a 'quality'. Must events then be defined in terms of those two? |
6440 | Universals can't just be words, because words themselves are universals [Russell] |
Full Idea: Those who dislike universals have thought that they could be merely words; the trouble with this view is that a word itself is a universal. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.14) | |
A reaction: Russell gradually lost his faith in most things, but never in universals. I find it unconvincing that we might dismiss nominalism so easily. I'm not sure why the application of the word 'cat' could not just be conventional. |
6430 | In epistemology we should emphasis the continuity between animal and human minds [Russell] |
Full Idea: It seems to me desirable in the theory of knowledge to emphasise the continuity between animal and human minds. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.11) | |
A reaction: I strongly agree with this, mainly because it avoids overemphasis on language in epistemology. It doesn't follow that animals know a lot, and there is a good case for saying that they don't actually 'know' anything, despite having true beliefs. |
6441 | Pragmatism judges by effects, but I judge truth by causes [Russell] |
Full Idea: Pragmatism holds that a belief is to be judged if it has certain effects, whereas I hold that an empirical belief is to be judged true if it has certain kinds of causes. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.15) | |
A reaction: I'm with Russell here, and this seems to me a convincing objection to pragmatism. The simple problem is that falsehoods can occasionally have very beneficial effects. Beliefs are made true by the facts, not by their consequences. |
6431 | Empiricists seem unclear what they mean by 'experience' [Russell] |
Full Idea: When I began to think about theory of knowledge, I found that none of the philosophers who emphasise 'experience' tells us what they mean by the word. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.11) | |
A reaction: A very significant comment about empiricism. Hume does not seem very clear about what an 'impression' is. Russell's problem has been dealt with intensively by modern empiricists, who discuss 'the given', and conceptualised perception. |
6444 | True belief about the time is not knowledge if I luckily observe a stopped clock at the right moment [Russell] |
Full Idea: Not all true beliefs are knowledge; the stock example to the contrary is that of a clock which has stopped by which I believe to be going and which I happen to look at when, by chance, it shows the right time. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.15) | |
A reaction: [in his 1948:112] Russell had spotted Gettier-type problems long before Gettier. The problem of lucky true beliefs dates back to Plato (Idea 2140). This example is also a problem for reliabilism, if the clock is usually working fine. |
6433 | Behaviourists struggle to explain memory and imagination, because they won't admit images [Russell] |
Full Idea: Behaviourists refuse to admit images because they cannot be observed from without, but this causes them difficulties when they attempt to explain either memory or imagination. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.13) | |
A reaction: This is a striking objection to behaviourism, and it is rarely mentioned in modern discussions of the topic. They might try denying the existence of private 'images', but that wouldn't be very plausible. |
6443 | Surprise is a criterion of error [Russell] |
Full Idea: Surprise is a criterion of error. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.15) | |
A reaction: Russell is not too precise about this, but it is a nice point. Surprise is thwarted expectation, which implies prior misjudgement. |
6427 | Unverifiable propositions about the remote past are still either true or false [Russell] |
Full Idea: There is no conceivable method by which we can discover whether the proposition 'It snowed on Manhattan Island on the 1st January in the year 1 A.D.' is true or false, but it seems preposterous to maintain that it is neither. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.10) | |
A reaction: I love this example, which seems so simple and so clear-cut. It criticises verificationism, and gives strong intuitive support for realism, and supports the law of excluded middle. |
6435 | You can believe the meaning of a sentence without thinking of the words [Russell] |
Full Idea: If you have just heard a loud clap of thunder, you believe what is expressed by 'there has just been a loud clap of thunder' even if no words come into your mind. | |
From: Bertrand Russell (My Philosophical Development [1959], Ch.13) | |
A reaction: This seems to me important, and accurate. We should not be too mesmerised by language. Animals have beliefs, and this is a nice example of an undeniable non-linguistic human belief. |