49 ideas
| 6267 | A culture needs to admit that knowledge is more extensive than just 'science' [Putnam] |
| Full Idea: The acknowledgement that the sphere of knowledge is wider than the sphere of 'science' seems to me to be a cultural necessity if we are to arrive at a sane and human view of ourselves or of science. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Intro) | |
| A reaction: A very nice remark, with which I intuitively agree, but then you are left with the problem of explaining how something can qualify as knowledge when it can't pass the stringent tests of science. How wide to we spread, and why? |
| 6272 | 'True' and 'refers' cannot be made scientically precise, but are fundamental to science [Putnam] |
| Full Idea: Some non-scientific knowledge is presupposed by science; for example, I have been arguing that 'refers' and 'true' cannot be made scientifically precise; yet truth is a fundamental term in logic - a precise science. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Lec VI) | |
| A reaction: We might ask whether we 'know' what 'true' and 'refers' mean, as opposed to being able to use them. If their usage doesn't count as knowledge, then we could still end up with all actual knowledge being somehow 'scientific'. |
| 6253 | Reason is our power of finding out true propositions [Hutcheson] |
| Full Idea: Reason is our power of finding out true propositions. | |
| From: Francis Hutcheson (Treatise 4: The Moral Sense [1728], §I) | |
| A reaction: This strikes me as a very good definition. I don't see how you can define reason without mentioning truth, and you can't believe in reason if you don't believe in truth. The concept of reason entails the concept of a good reason. |
| 6276 | 'The rug is green' might be warrantedly assertible even though the rug is not green [Putnam] |
| Full Idea: 'The rug is green' might be warrantedly assertible even though the rug is not green. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Pt Three) | |
| A reaction: The word 'warranted' seems to be ambiguous in modern philosophy. See Idea 6150. There seem to be internalist and externalist versions. It seems clear to say that a belief could be well-justified and yet false. |
| 6266 | We need the correspondence theory of truth to understand language and science [Putnam] |
| Full Idea: A correspondence theory of truth is needed to understand how language works, and how science works. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Intro) | |
| A reaction: Putnam retreated from this position to a more pragmatic one later on, but all my sympathies are with the present view, despite being repeatedly told by modern philosophers that I am wrong. See McGinn (Idea 6085) and Searle (Idea 3508). |
| 6277 | Correspondence between concepts and unconceptualised reality is impossible [Putnam] |
| Full Idea: The great nineteenth century argument against the correspondence theory of truth was that one cannot think of truth as correspondence to facts (or 'reality') because one would need to compare concepts directly with unconceptualised reality. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Pt Three) | |
| A reaction: Presumably the criticism was offered by idealists, who preferred a coherence theory. The defence is to say that there is a confusion here between a concept and the contents of a concept. The contents of a concept are designed to be facts. |
| 6264 | In Tarski's definition, you understand 'true' if you accept the notions of the object language [Putnam] |
| Full Idea: Anyone who accepts the notions of whatever object language is in question - and this can be chosen arbitrarily - can also understand 'true' as defined by Tarski for that object language. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Intro) | |
| A reaction: Thus if we say "'snow is white' is true iff snow is white", then if you 'accept the notion' that snow is white in English, you understand what 'true' means. This seems to leave you with the meaning of 'snow is white' being its truth conditions. |
| 6265 | Tarski has given a correct account of the formal logic of 'true', but there is more to the concept [Putnam] |
| Full Idea: What Tarski has done is to give us a perfectly correct account of the formal logic of the concept 'true', but the formal logic of the concept is not all there is to the notion of truth. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Intro) | |
| A reaction: I find this refreshing. A lot of modern philosophers seem to think that truth is no longer an interesting philosophical topic, because deflationary accounts have sidelined it, but I take the concept to be at the heart of metaphysics. |
| 6269 | Only Tarski has found a way to define 'true' [Putnam] |
| Full Idea: There is only one way anyone knows how to define 'true' and that is Tarski's way. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Lec II.5) | |
| A reaction: However, Davidson wrote a paper called 'On the Folly of Trying to Define Truth', which seems to reject even Tarski. Also bear in mind Putnam's earlier remark (Idea 6265) that there is more to truth than Tarski's definition. Just take 'true' as primitive. |
| 17926 | Rejecting double negation elimination undermines reductio proofs [Colyvan] |
| Full Idea: The intuitionist rejection of double negation elimination undermines the important reductio ad absurdum proof in classical mathematics. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 1.1.3) |
| 17925 | Showing a disproof is impossible is not a proof, so don't eliminate double negation [Colyvan] |
| Full Idea: In intuitionist logic double negation elimination fails. After all, proving that there is no proof that there can't be a proof of S is not the same thing as having a proof of S. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 1.1.3) | |
| A reaction: I do like people like Colyvan who explain things clearly. All of this difficult stuff is understandable, if only someone makes the effort to explain it properly. |
| 17924 | Excluded middle says P or not-P; bivalence says P is either true or false [Colyvan] |
| Full Idea: The law of excluded middle (for every proposition P, either P or not-P) must be carefully distinguished from its semantic counterpart bivalence, that every proposition is either true or false. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 1.1.3) | |
| A reaction: So excluded middle makes no reference to the actual truth or falsity of P. It merely says P excludes not-P, and vice versa. |
| 17929 | Löwenheim proved his result for a first-order sentence, and Skolem generalised it [Colyvan] |
| Full Idea: Löwenheim proved that if a first-order sentence has a model at all, it has a countable model. ...Skolem generalised this result to systems of first-order sentences. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 2.1.2) |
| 17930 | Axioms are 'categorical' if all of their models are isomorphic [Colyvan] |
| Full Idea: A set of axioms is said to be 'categorical' if all models of the axioms in question are isomorphic. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 2.1.2) | |
| A reaction: The best example is the Peano Axioms, which are 'true up to isomorphism'. Set theory axioms are only 'quasi-isomorphic'. |
| 17928 | Ordinal numbers represent order relations [Colyvan] |
| Full Idea: Ordinal numbers represent order relations. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 1.2.3 n17) |
| 17923 | Intuitionists only accept a few safe infinities [Colyvan] |
| Full Idea: For intuitionists, all but the smallest, most well-behaved infinities are rejected. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 1.1.3) | |
| A reaction: The intuitionist idea is to only accept what can be clearly constructed or proved. |
| 17941 | Infinitesimals were sometimes zero, and sometimes close to zero [Colyvan] |
| Full Idea: The problem with infinitesimals is that in some places they behaved like real numbers close to zero but in other places they behaved like zero. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 7.1.2) | |
| A reaction: Colyvan gives an example, of differentiating a polynomial. |
| 17922 | Reducing real numbers to rationals suggested arithmetic as the foundation of maths [Colyvan] |
| Full Idea: Given Dedekind's reduction of real numbers to sequences of rational numbers, and other known reductions in mathematics, it was tempting to see basic arithmetic as the foundation of mathematics. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 1.1.1) | |
| A reaction: The reduction is the famous Dedekind 'cut'. Nowadays theorists seem to be more abstract (Category Theory, for example) instead of reductionist. |
| 17936 | Transfinite induction moves from all cases, up to the limit ordinal [Colyvan] |
| Full Idea: Transfinite inductions are inductive proofs that include an extra step to show that if the statement holds for all cases less than some limit ordinal, the statement also holds for the limit ordinal. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 5.2.1 n11) |
| 17940 | Most mathematical proofs are using set theory, but without saying so [Colyvan] |
| Full Idea: Most mathematical proofs, outside of set theory, do not explicitly state the set theory being employed. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 7.1.1) |
| 17931 | Structuralism say only 'up to isomorphism' matters because that is all there is to it [Colyvan] |
| Full Idea: Structuralism is able to explain why mathematicians are typically only interested in describing the objects they study up to isomorphism - for that is all there is to describe. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 3.1.2) |
| 17932 | If 'in re' structures relies on the world, does the world contain rich enough structures? [Colyvan] |
| Full Idea: In re structuralism does not posit anything other than the kinds of structures that are in fact found in the world. ...The problem is that the world may not provide rich enough structures for the mathematics. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 3.1.2) | |
| A reaction: You can perceive a repeating pattern in the world, without any interest in how far the repetitions extend. |
| 6280 | Realism is a theory, which explains the convergence of science and the success of language [Putnam] |
| Full Idea: Realism is an empirical theory; it explains the convergence of scientific theories, where earlier theories are often limiting cases of later theories (which is why theoretical terms preserve their reference); and it explains the success of language. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Pt Four) | |
| A reaction: I agree. Personally, I think of Plato's Theory of Forms and all religions as empirical theories. The response from anti-realists is generally to undermine confidence in the evidence which these 'empirical theories' are said to explain. |
| 6284 | If a tautology is immune from revision, why would that make it true? [Putnam] |
| Full Idea: If we held, say, 'All unmarried men are unmarried' as absolutely immune from revision, why would this make it true? | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Pt Four) | |
| A reaction: A very nice question. Like most American philosophers, Putnam accepts Quine's attack on the unrevisability of analytic truths. His point here is that defenders of analytic truths are probably desperate to preserve basic truths, but it won't work. |
| 6273 | Knowledge depends on believing others, which must be innate, as inferences are not strong enough [Putnam] |
| Full Idea: Our ability to picture how people are likely to respond may well be innate; indeed, our disposition to believe what other people tell us (which is fundamental to knowledge) could hardly be an inference, as that isn’t good enough for knowledge. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Lec VI) | |
| A reaction: An interesting claim. There could be an intermediate situation, which is a hard-wired non-conscious inference. When dismantled, the 'innate' brain circuits for assessing testimony could turn out to work on logic and evidence. |
| 6274 | Empathy may not give knowledge, but it can give plausibility or right opinion [Putnam] |
| Full Idea: Empathy with others may give less than 'Knowledge', but it gives more than mere logical or physical possibility; it gives plausibility, or (to revive Platonic terminology) it provides 'right opinion'. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Lec VI) | |
| A reaction: See Ideas 174 and 2140 for Plato. Putnam is exploring areas of knowledge outside the limits of strict science. Behind this claim seems to lie the Principle of Charity (3971), but a gang of systematic liars (e.g. evil students) would be a problem case. |
| 17943 | Probability supports Bayesianism better as degrees of belief than as ratios of frequencies [Colyvan] |
| Full Idea: Those who see probabilities as ratios of frequencies can't use Bayes's Theorem if there is no objective prior probability. Those who accept prior probabilities tend to opt for a subjectivist account, where probabilities are degrees of belief. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 9.1.8) | |
| A reaction: [compressed] |
| 17939 | Mathematics can reveal structural similarities in diverse systems [Colyvan] |
| Full Idea: Mathematics can demonstrate structural similarities between systems (e.g. missing population periods and the gaps in the rings of Saturn). | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 6.3.2) | |
| A reaction: [Colyvan expounds the details of his two examples] It is these sorts of results that get people enthusiastic about the mathematics embedded in nature. A misunderstanding, I think. |
| 17938 | Mathematics can show why some surprising events have to occur [Colyvan] |
| Full Idea: Mathematics can show that under a broad range of conditions, something initially surprising must occur (e.g. the hexagonal structure of honeycomb). | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 6.3.2) |
| 17934 | Proof by cases (by 'exhaustion') is said to be unexplanatory [Colyvan] |
| Full Idea: Another style of proof often cited as unexplanatory are brute-force methods such as proof by cases (or proof by exhaustion). | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 5.2.1) |
| 17933 | Reductio proofs do not seem to be very explanatory [Colyvan] |
| Full Idea: One kind of proof that is thought to be unexplanatory is the 'reductio' proof. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 5.2.1) | |
| A reaction: Presumably you generate a contradiction, but are given no indication of why the contradiction has arisen? Tracking back might reveal the source of the problem? Colyvan thinks reductio can be explanatory. |
| 17935 | If inductive proofs hold because of the structure of natural numbers, they may explain theorems [Colyvan] |
| Full Idea: It might be argued that any proof by induction is revealing the explanation of the theorem, namely, that it holds by virtue of the structure of the natural numbers. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 5.2.1) | |
| A reaction: This is because induction characterises the natural numbers, in the Peano Axioms. |
| 17942 | Can a proof that no one understands (of the four-colour theorem) really be a proof? [Colyvan] |
| Full Idea: The proof of the four-colour theorem raises questions about whether a 'proof' that no one understands is a proof. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 9.1.6) | |
| A reaction: The point is that the theorem (that you can colour countries on a map with just four colours) was proved with the help of a computer. |
| 17084 | You can't decide which explanations are good if you don't attend to the interest-relative aspects [Putnam] |
| Full Idea: Explanation is an interest-relative notion …explanation has to be partly a pragmatic concept. To regard the 'pragmatics' of explanation as no part of the concept is to abdicate the job of figuring out what makes an explanation good. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], p. 41-2), quoted by David-Hillel Ruben - Explaining Explanation Ch 1 | |
| A reaction: I suppose this is just obvious, depending on how far you want to take the 'interest-relative' bit. If a fool is fobbed off with a trivial explanation, there must be some non-relative criterion for assessing that. |
| 17937 | Mathematical generalisation is by extending a system, or by abstracting away from it [Colyvan] |
| Full Idea: One type of generalisation in mathematics extends a system to go beyond what is was originally set up for; another kind involves abstracting away from some details in order to capture similarities between different systems. | |
| From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 5.2.2) |
| 6282 | Theory of meaning presupposes theory of understanding and reference [Putnam] |
| Full Idea: Theory of meaning presupposes theory of understanding and reference. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Pt Four) | |
| A reaction: How can you have a theory of understanding without a meaning that requires to be understood? Personally I think about the minds of small animals when pondering this, and that seems to put reference and truth at the front of the queue. |
| 6281 | Truth conditions can't explain understanding a sentence, because that in turn needs explanation [Putnam] |
| Full Idea: You can't treat understanding a sentence as knowing its truth conditions, because it then becomes unintelligible what that knowledge in turn consists in. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Pt Four) | |
| A reaction: The implication, I take it, is circularity; how can you specify truth conditions if you don't understand sentences? Putnam here agrees with Dummett that verification must be involved. Something has to be taken as axiomatic in all this. |
| 6278 | We should reject the view that truth is prior to meaning [Putnam] |
| Full Idea: I am suggesting that we reject the view that truth (based on the semantic theory) is prior to meaning. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Pt Three) | |
| A reaction: It is a nice question which of truth or meaning has logical priority. One might start by speculating about how and why animals think. A moth attracted to flame is probably working on truth without much that could be called 'meaning'. |
| 6271 | How reference is specified is not what reference is [Putnam] |
| Full Idea: A theory of how reference is specified isn't a theory of what reference is. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Lec V) | |
| A reaction: A simple and important point. We may achieve reference by naming, describing, grunting or pointing, but the question is, what have we achieved when we get there? |
| 6268 | The claim that scientific terms are incommensurable can be blocked if scientific terms are not descriptions [Putnam] |
| Full Idea: The line of reasoning of Kuhn and Feyerabend can be blocked by arguing (as I have in various places, and as Saul Kripke has) that scientific terms are not synonymous with descriptions. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Lec II.2) | |
| A reaction: A nice clear statement of the motivation for creating the causal theory of reference. See Idea 6162. We could still go back and ask whether we could block scientific relativism by rethinking how descriptions work, instead of abandoning them. |
| 6279 | A private language could work with reference and beliefs, and wouldn't need meaning [Putnam] |
| Full Idea: A language made up and used by a being who belonged to no community would have no need for such a concept as the 'meaning' of a term. To state the reference of each term and what the language speaker believes is to tell the whole story. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Pt Three) | |
| A reaction: A subtle response to Wittgenstein's claim (e.g. Ideas 4152,4158), but I am not sure what Putnam means. I would have thought that beliefs had to be embodied in propositions. They may not need 'meaning' quite as urgently as sentences, but still… |
| 6270 | The correct translation is the one that explains the speaker's behaviour [Putnam] |
| Full Idea: What it is to be a correct translation is to be the translation that best explains the behaviour of the speaker. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Lec III) | |
| A reaction: This seems fairly close to Quine, but rather puzzlingly uses the word 'correct'. If our criteria of translation are purely behavioural, there is no way we can be correct after one word ('gavagai'), so at what point does it become 'correct'? |
| 6283 | Language maps the world in many ways (because it maps onto other languages in many ways) [Putnam] |
| Full Idea: We could say that the language has more than one correct way of being mapped onto the world (it must, since it has more than one way of being correctly mapped onto a language which is itself correctly mapped onto the world). | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Pt Four) | |
| A reaction: This spells out nicely the significance of Quine's 'indeterminacy of translation'. Others have pointed out that the fact that language maps onto world in many ways need not be anti-realist; the world is endless, and language is limited. |
| 6275 | You can't say 'most speaker's beliefs are true'; in some areas this is not so, and you can't count beliefs [Putnam] |
| Full Idea: The maxim that 'most of a speaker's beliefs are true' as an a priori principle governing radical translation seems to me to go too far; first, I don't know how to count beliefs; second, most people's beliefs on some topics (philosophy) are probably false. | |
| From: Hilary Putnam (Meaning and the Moral Sciences [1978], Pt Three) | |
| A reaction: Putnam prefers a pragmatic view, where charity is applicable if behaviour is involved. Philosophy is too purely theoretical. The extent to which Charity should apply in philosophy seminars is a nice question, which all students should test in practice. |
| 6256 | Can't the moral sense make mistakes, as the other senses do? [Hutcheson] |
| Full Idea: Can there not be a right and wrong state of our moral sense, as there is in our other senses? | |
| From: Francis Hutcheson (Treatise 4: The Moral Sense [1728], §IV) | |
| A reaction: Hutcheson replies by saying something like they are both fully reliable in normal conditions. It remains, though, a very good question for the intuitionist to face, as the moral sense is supposed to be direct and reliable, but how do you check? |
| 6252 | Happiness is a pleasant sensation, or continued state of such sensations [Hutcheson] |
| Full Idea: In the following discourse, happiness denotes pleasant sensation of any kind, or continued state of such sensations. | |
| From: Francis Hutcheson (Treatise 4: The Moral Sense [1728], Intro) | |
| A reaction: This is a very long way from Greek eudaimonia. Hutcheson seems to imply that I would be happy if I got high on drugs after my family had just burnt to death. Socrates points out that scratching an itch is a very pleasant sensation (Idea 132). |
| 6257 | You can't form moral rules without an end, which needs feelings and a moral sense [Hutcheson] |
| Full Idea: What rule of actions can be formed, without relation to some end proposed? Or what end can be proposed, without presupposing instincts, desires, affections, or a moral sense, it will not be easy to explain. | |
| From: Francis Hutcheson (Treatise 4: The Moral Sense [1728], §IV) | |
| A reaction: We have no reason to think that 'instincts, desires and affections' will give us the remotest guidance on how to behave morally well (though we would expect them to aid our survival). How could a moral sense give a reason, without spotting a rule? |
| 6254 | We are asked to follow God's ends because he is our benefactor, but why must we do that? [Hutcheson] |
| Full Idea: The reasons assigned for actions are such as 'It is the end proposed by the Deity'. But why do we approve concurring with the divine ends? The reason is given 'He is our benefactor', but then, for what reason do we approve concurrence with a benefactor? | |
| From: Francis Hutcheson (Treatise 4: The Moral Sense [1728], §I) | |
| A reaction: Characteristic of what MacIntyre calls the 'Enlightenment Project', which is the application of Cartesian scepticism to proving the foundations of morals. Proof beyond proof is continually demanded. If you could meet God, you would obey without question. |
| 6255 | Why may God not have a superior moral sense very similar to ours? [Hutcheson] |
| Full Idea: Why may not the Deity have something of a superior kind, analogous to our moral sense, essential to him? | |
| From: Francis Hutcheson (Treatise 4: The Moral Sense [1728], §I) | |
| A reaction: This is Plato's notion of the gods, as beings who are profoundly wise, and understand all the great moral truths, but are not the actual originators of those truths. The idea that God creates morality actually serves to undermine morality. |