70 ideas
13466 | We are all post-Kantians, because he set the current agenda for philosophy [Hart,WD] |
Full Idea: We are all post-Kantians, ...because Kant set an agenda for philosophy that we are still working through. | |
From: William D. Hart (The Evolution of Logic [2010], 2) | |
A reaction: Hart says that the main agenda is set by Kant's desire to defend the principle of sufficient reason against Hume's attack on causation. I would take it more generally to be the assessment of metaphysics, and of a priori knowledge. |
13477 | The problems are the monuments of philosophy [Hart,WD] |
Full Idea: The real monuments of philosophy are its problems. | |
From: William D. Hart (The Evolution of Logic [2010], 2) | |
A reaction: Presumably he means '....rather than its solutions'. No other subject would be very happy with that sort of claim. Compare Idea 8243. A complaint against analytic philosophy is that it has achieved no consensus at all. |
13515 | To study abstract problems, some knowledge of set theory is essential [Hart,WD] |
Full Idea: By now, no education in abstract pursuits is adequate without some familiarity with sets. | |
From: William D. Hart (The Evolution of Logic [2010], 10) | |
A reaction: A heart-sinking observation for those who aspire to study metaphysics and modality. The question is, what will count as 'some' familiarity? Are only professional logicians now allowed to be proper philosophers? |
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'. |
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). |
13469 | Tarski showed how we could have a correspondence theory of truth, without using 'facts' [Hart,WD] |
Full Idea: It is an ancient and honourable view that truth is correspondence to fact; Tarski showed us how to do without facts here. | |
From: William D. Hart (The Evolution of Logic [2010], 2) | |
A reaction: This is a very interesting spin on Tarski, who certainly seems to endorse the correspondence theory, even while apparently inventing a new 'semantic' theory of truth. It is controversial how far Tarski's theory really is a 'correspondence' theory. |
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. |
13504 | Truth for sentences is satisfaction of formulae; for sentences, either all sequences satisfy it (true) or none do [Hart,WD] |
Full Idea: We explain truth for sentences in terms of satisfaction of formulae. The crux here is that for a sentence, either all sequences satisfy it or none do (with no middle ground). For formulae, some sequences may satisfy it and others not. | |
From: William D. Hart (The Evolution of Logic [2010], 4) | |
A reaction: This is the hardest part of Tarski's theory of truth to grasp. |
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. |
13503 | A first-order language has an infinity of T-sentences, which cannot add up to a definition of truth [Hart,WD] |
Full Idea: In any first-order language, there are infinitely many T-sentences. Since definitions should be finite, the agglomeration of all the T-sentences is not a definition of truth. | |
From: William D. Hart (The Evolution of Logic [2010], 4) | |
A reaction: This may be a warning shot aimed at Davidson's extensive use of Tarski's formal account in his own views on meaning in natural language. |
13500 | Conditional Proof: infer a conditional, if the consequent can be deduced from the antecedent [Hart,WD] |
Full Idea: A 'conditional proof' licenses inferences to a conditional from a deduction of its consequent from its antecedent. | |
From: William D. Hart (The Evolution of Logic [2010], 4) | |
A reaction: That is, a proof can be enshrined in an arrow. |
13502 | ∃y... is read as 'There exists an individual, call it y, such that...', and not 'There exists a y such that...' [Hart,WD] |
Full Idea: When a quantifier is attached to a variable, as in '∃(y)....', then it should be read as 'There exists an individual, call it y, such that....'. One should not read it as 'There exists a y such that...', which would attach predicate to quantifier. | |
From: William D. Hart (The Evolution of Logic [2010], 4) | |
A reaction: The point is to make clear that in classical logic the predicates attach to the objects, and not to some formal component like a quantifier. |
13456 | Set theory articulates the concept of order (through relations) [Hart,WD] |
Full Idea: It is set theory, and more specifically the theory of relations, that articulates order. | |
From: William D. Hart (The Evolution of Logic [2010]) | |
A reaction: It would seem that we mainly need set theory in order to talk accurately about order, and about infinity. The two come together in the study of the ordinal numbers. |
13497 | Nowadays ZFC and NBG are the set theories; types are dead, and NF is only useful for the whole universe [Hart,WD] |
Full Idea: The theory of types is a thing of the past. There is now nothing to choose between ZFC and NBG (Neumann-Bernays-Gödel). NF (Quine's) is a more specialized taste, but is a place to look if you want the universe. | |
From: William D. Hart (The Evolution of Logic [2010], 3) |
13443 | ∈ relates across layers, while ⊆ relates within layers [Hart,WD] |
Full Idea: ∈ relates across layers (Plato is a member of his unit set and the set of people), while ⊆ relates within layers (the singleton of Plato is a subset of the set of people). This distinction only became clear in the 19th century. | |
From: William D. Hart (The Evolution of Logic [2010], 1) | |
A reaction: Getting these two clear may be the most important distinction needed to understand how set theory works. |
13442 | Without the empty set we could not form a∩b without checking that a and b meet [Hart,WD] |
Full Idea: Without the empty set, disjoint sets would have no intersection, and we could not form a∩b without checking that a and b meet. This is an example of the utility of the empty set. | |
From: William D. Hart (The Evolution of Logic [2010], 1) | |
A reaction: A novice might plausibly ask why there should be an intersection for every pair of sets, if they have nothing in common except for containing this little puff of nothingness. But then what do novices know? |
13493 | In the modern view, foundation is the heart of the way to do set theory [Hart,WD] |
Full Idea: In the second half of the twentieth century there emerged the opinion that foundation is the heart of the way to do set theory. | |
From: William D. Hart (The Evolution of Logic [2010], 3) | |
A reaction: It is foundation which is the central axiom of the iterative conception of sets, where each level of sets is built on previous levels, and they are all 'well-founded'. |
13495 | Foundation Axiom: an nonempty set has a member disjoint from it [Hart,WD] |
Full Idea: The usual statement of Foundation is that any nonempty set has a member disjoint from it. This phrasing is ordinal-free and closer to the primitives of ZFC. | |
From: William D. Hart (The Evolution of Logic [2010], 3) |
13461 | We can choose from finite and evident sets, but not from infinite opaque ones [Hart,WD] |
Full Idea: When a set is finite, we can prove it has a choice function (∀x x∈A → f(x)∈A), but we need an axiom when A is infinite and the members opaque. From infinite shoes we can pick a left one, but from socks we need the axiom of choice. | |
From: William D. Hart (The Evolution of Logic [2010], 1) | |
A reaction: The socks example in from Russell 1919:126. |
13462 | With the Axiom of Choice every set can be well-ordered [Hart,WD] |
Full Idea: It follows from the Axiom of Choice that every set can be well-ordered. | |
From: William D. Hart (The Evolution of Logic [2010], 1) | |
A reaction: For 'well-ordered' see Idea 13460. Every set can be ordered with a least member. |
13516 | If we accept that V=L, it seems to settle all the open questions of set theory [Hart,WD] |
Full Idea: It has been said (by Burt Dreben) that the only reason set theorists do not generally buy the view that V = L is that it would put them out of business by settling their open questions. | |
From: William D. Hart (The Evolution of Logic [2010], 10) | |
A reaction: Hart says V=L breaks with the interative conception of sets at level ω+1, which is countable is the constructible view, but has continuum many in the cumulative (iterative) hierarch. The constructible V=L view is anti-platonist. |
13441 | Naïve set theory has trouble with comprehension, the claim that every predicate has an extension [Hart,WD] |
Full Idea: 'Comprehension' is the assumption that every predicate has an extension. Naïve set theory is the theory whose axioms are extensionality and comprehension, and comprehension is thought to be its naivety. | |
From: William D. Hart (The Evolution of Logic [2010], 1) | |
A reaction: This doesn't, of course, mean that there couldn't be a more modest version of comprehension. The notorious difficulty come with the discovery of self-referring predicates which can't possibly have extensions. |
13494 | The iterative conception may not be necessary, and may have fixed points or infinitely descending chains [Hart,WD] |
Full Idea: That the iterative sets suffice for most of ZFC does not show they are necessary, nor is it evident that the set of operations has no fixed points (as 0 is a fixed point for square-of), and no infinitely descending chains (like negative integers). | |
From: William D. Hart (The Evolution of Logic [2010], 3) | |
A reaction: People don't seem to worry that they aren't 'necessary', and further measures are possible to block infinitely descending chains. |
13457 | A 'partial ordering' is irreflexive and transitive; the sets are ordered, but not the subsets [Hart,WD] |
Full Idea: We say that a binary relation R 'partially orders' a field A just in case R is irreflexive (so that nothing bears R to itself) and transitive. When the set is {a,b}, its subsets {a} and {b} are incomparable in a partial ordering. | |
From: William D. Hart (The Evolution of Logic [2010], 1) |
13458 | A partial ordering becomes 'total' if any two members of its field are comparable [Hart,WD] |
Full Idea: A partial ordering is a 'total ordering' just in case any two members of its field are comparable, that is, either a is R to b, or b is R to a, or a is b. | |
From: William D. Hart (The Evolution of Logic [2010], 1) | |
A reaction: See Idea 13457 for 'partial ordering'. The three conditions are known as the 'trichotomy' condition. |
13490 | Von Neumann defines α<β as α∈β [Hart,WD] |
Full Idea: One of the glories of Von Neumann's theory of numbers is to define α < β to mean that α ∈ β. | |
From: William D. Hart (The Evolution of Logic [2010], 3) |
13460 | 'Well-ordering' must have a least member, so it does the natural numbers but not the integers [Hart,WD] |
Full Idea: A total order 'well-orders' its field just in case any nonempty subset B of its field has an R-least member, that is, there is a b in B such that for any a in B different from b, b bears R to a. So less-than well-orders natural numbers, but not integers. | |
From: William D. Hart (The Evolution of Logic [2010], 1) | |
A reaction: The natural numbers have a starting point, but the integers are infinite in both directions. In plain English, an order is 'well-ordered' if there is a starting point. |
13481 | Maybe sets should be rethought in terms of the even more basic categories [Hart,WD] |
Full Idea: Some have claimed that sets should be rethought in terms of still more basic things, categories. | |
From: William D. Hart (The Evolution of Logic [2010], 2) | |
A reaction: [He cites F.William Lawvere 1966] It appears to the the context of foundations for mathematics that he has in mind. |
21677 | How can the not-true fail to be false, or the not-false fail to be true? [Cicero] |
Full Idea: How can something that is not true not be false, or how can something that is not false not be true? | |
From: M. Tullius Cicero (On Fate ('De fato') [c.44 BCE], 16.38) | |
A reaction: We must at least distinguish between whether the contrary thing is not actually true, or whether we are prepared to assert that it is not true. The disjunction may seem to be a false dichotomy. 'He isn't good' may not entail 'he is evil'. |
13506 | The universal quantifier can't really mean 'all', because there is no universal set [Hart,WD] |
Full Idea: All the main set theories deny that there is a set of which everything is a member. No interpretation has a domain with everything in it. So the universal quantifier never gets to mean everything all at once; 'all' does not mean all. | |
From: William D. Hart (The Evolution of Logic [2010], 4) | |
A reaction: Could you have an 'uncompleted' universal set, in the spirit of uncompleted infinities? In ordinary English we can talk about 'absolutely everything' - we just can't define a set of everything. Must we 'define' our domain? |
13513 | Models are ways the world might be from a first-order point of view [Hart,WD] |
Full Idea: Models are ways the world might be from a first-order point of view. | |
From: William D. Hart (The Evolution of Logic [2010], 9) |
13505 | Model theory studies how set theory can model sets of sentences [Hart,WD] |
Full Idea: Modern model theory investigates which set theoretic structures are models for which collections of sentences. | |
From: William D. Hart (The Evolution of Logic [2010], 4) | |
A reaction: So first you must choose your set theory (see Idea 13497). Then you presumably look at how to formalise sentences, and then look at the really tricky ones, many of which will involve various degrees of infinity. |
13511 | Model theory is mostly confined to first-order theories [Hart,WD] |
Full Idea: There is no developed methematics of models for second-order theories, so for the most part, model theory is about models for first-order theories. | |
From: William D. Hart (The Evolution of Logic [2010], 9) |
13512 | Modern model theory begins with the proof of Los's Conjecture in 1962 [Hart,WD] |
Full Idea: The beginning of modern model theory was when Morley proved Los's Conjecture in 1962 - that a complete theory in a countable language categorical in one uncountable cardinal is categorical in all. | |
From: William D. Hart (The Evolution of Logic [2010], 9) |
13496 | First-order logic is 'compact': consequences of a set are consequences of a finite subset [Hart,WD] |
Full Idea: First-order logic is 'compact', which means that any logical consequence of a set (finite or infinite) of first-order sentences is a logical consequence of a finite subset of those sentences. | |
From: William D. Hart (The Evolution of Logic [2010], 3) |
13484 | Berry's Paradox: we succeed in referring to a number, with a term which says we can't do that [Hart,WD] |
Full Idea: Berry's Paradox: by the least number principle 'the least number denoted by no description of fewer than 79 letters' exists, but we just referred to it using a description of 77 letters. | |
From: William D. Hart (The Evolution of Logic [2010], 3) | |
A reaction: I struggle with this. If I refer to 'an object to which no human being could possibly refer', have I just referred to something? Graham Priest likes this sort of idea. |
13482 | The Burali-Forti paradox is a crisis for Cantor's ordinals [Hart,WD] |
Full Idea: The Burali-Forti Paradox was a crisis for Cantor's theory of ordinal numbers. | |
From: William D. Hart (The Evolution of Logic [2010], 3) |
13507 | The machinery used to solve the Liar can be rejigged to produce a new Liar [Hart,WD] |
Full Idea: In effect, the machinery introduced to solve the liar can always be rejigged to yield another version the liar. | |
From: William D. Hart (The Evolution of Logic [2010], 4) | |
A reaction: [He cites Hans Herzberger 1980-81] The machinery is Tarski's device of only talking about sentences of a language by using a 'metalanguage'. |
13459 | The less-than relation < well-orders, and partially orders, and totally orders the ordinal numbers [Hart,WD] |
Full Idea: We can show (using the axiom of choice) that the less-than relation, <, well-orders the ordinals, ...and that it partially orders the ordinals, ...and that it totally orders the ordinals. | |
From: William D. Hart (The Evolution of Logic [2010], 1) |
13463 | There are at least as many infinite cardinals as transfinite ordinals (because they will map) [Hart,WD] |
Full Idea: Since we can map the transfinite ordinals one-one into the infinite cardinals, there are at least as many infinite cardinals as transfinite ordinals. | |
From: William D. Hart (The Evolution of Logic [2010], 1) |
13491 | The axiom of infinity with separation gives a least limit ordinal ω [Hart,WD] |
Full Idea: The axiom of infinity with separation yields a least limit ordinal, which is called ω. | |
From: William D. Hart (The Evolution of Logic [2010], 3) |
13492 | Von Neumann's ordinals generalise into the transfinite better, because Zermelo's ω is a singleton [Hart,WD] |
Full Idea: It is easier to generalize von Neumann's finite ordinals into the transfinite. All Zermelo's nonzero finite ordinals are singletons, but if ω were a singleton it is hard to see how if could fail to be the successor of its member and so not a limit. | |
From: William D. Hart (The Evolution of Logic [2010], 3) |
13446 | 19th century arithmetization of analysis isolated the real numbers from geometry [Hart,WD] |
Full Idea: The real numbers were not isolated from geometry until the arithmetization of analysis during the nineteenth century. | |
From: William D. Hart (The Evolution of Logic [2010], 1) |
13509 | We can establish truths about infinite numbers by means of induction [Hart,WD] |
Full Idea: Mathematical induction is a way to establish truths about the infinity of natural numbers by a finite proof. | |
From: William D. Hart (The Evolution of Logic [2010], 5) | |
A reaction: If there are truths about infinities, it is very tempting to infer that the infinities must therefore 'exist'. A nice, and large, question in philosophy is whether there can be truths without corresponding implications of existence. |
13474 | Euclid has a unique parallel, spherical geometry has none, and saddle geometry has several [Hart,WD] |
Full Idea: There is a familiar comparison between Euclid (unique parallel) and 'spherical' geometry (no parallel) and 'saddle' geometry (several parallels). | |
From: William D. Hart (The Evolution of Logic [2010], 2) |
13471 | Mathematics makes existence claims, but philosophers usually say those are never analytic [Hart,WD] |
Full Idea: The thesis that no existence proposition is analytic is one of the few constants in philosophical consciences, but there are many existence claims in mathematics, such as the infinity of primes, five regular solids, and certain undecidable propositions. | |
From: William D. Hart (The Evolution of Logic [2010], 2) |
13488 | Mass words do not have plurals, or numerical adjectives, or use 'fewer' [Hart,WD] |
Full Idea: Jespersen calls a noun a mass word when it has no plural, does not take numerical adjectives, and does not take 'fewer'. | |
From: William D. Hart (The Evolution of Logic [2010], 3) | |
A reaction: Jespersen was a great linguistics expert. |
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. |
13480 | Fregean self-evidence is an intrinsic property of basic truths, rules and definitions [Hart,WD] |
Full Idea: The conception of Frege is that self-evidence is an intrinsic property of the basic truths, rules, and thoughts expressed by definitions. | |
From: William D. Hart (The Evolution of Logic [2010], p.350) | |
A reaction: The problem is always that what appears to be self-evident may turn out to be wrong. Presumably the effort of arriving at a definition ought to clarify and support the self-evident ingredient. |
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. |
13476 | The failure of key assumptions in geometry, mereology and set theory throw doubt on the a priori [Hart,WD] |
Full Idea: In the case of the parallels postulate, Euclid's fifth axiom (the whole is greater than the part), and comprehension, saying was believing for a while, but what was said was false. This should make a shrewd philosopher sceptical about a priori knowledge. | |
From: William D. Hart (The Evolution of Logic [2010], 2) | |
A reaction: Euclid's fifth is challenged by infinite numbers, and comprehension is challenged by Russell's paradox. I can't see a defender of the a priori being greatly worried about these cases. No one ever said we would be right - in doing arithmetic, for example. |
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. |
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. |
13475 | The Fregean concept of GREEN is a function assigning true to green things, and false to the rest [Hart,WD] |
Full Idea: A Fregean concept is a function that assigns to each object a truth value. So instead of the colour green, the concept GREEN assigns truth to each green thing, but falsity to anything else. | |
From: William D. Hart (The Evolution of Logic [2010], 2) | |
A reaction: This would seem to immediately hit the renate/cordate problem, if there was a world in which all and only the green things happened to be square. How could Frege then distinguish the green from the square? Compare Idea 8245. |
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. |
21667 | Oratory and philosophy are closely allied; orators borrow from philosophy, and ornament it [Cicero] |
Full Idea: There is a close alliance between the orator and the philosophical system of which I am a follower, since the orator borrows subtlely from the Academy, and repays the loan by giving to it a copious and flowing style and rhetorical ornament. | |
From: M. Tullius Cicero (On Fate ('De fato') [c.44 BCE], 02.03) | |
A reaction: It is a misundertanding to think that rhetoric and philosophy are seen as in necessary opposition. Philosophers just seemed to think that oratory works a lot better if it is truthful. |
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. |
21678 | If desire is not in our power then neither are choices, so we should not be praised or punished [Cicero] |
Full Idea: If the cause of desire is not situated within us, even desire itself is also not in our power. ...It follows that neither assent nor action is in our power. Hence there is no justice in either praise or blame, either honours or punishments. | |
From: M. Tullius Cicero (On Fate ('De fato') [c.44 BCE], 17.40) | |
A reaction: This is the view of 'old philosophers', but I'm unsure which ones. Cicero spurns this view. It is obvious that the causes of our desires are largely out of our control. Responsibility seems to concern what we do about our desires. |