35 ideas
| 2352 | The job of the philosopher is to distinguish facts about the world from conventions [Putnam] |
| Full Idea: It is the job of the philosopher to distinguish what is fact and what is convention in our theorising about the world. | |
| From: Hilary Putnam (Representation and Reality [1988], §7 p.112) | |
| A reaction: This may well be the entire truth about philosophy. It begins with the Nomos-Physis debate in ancient Athens, and it turns out to be the key issue in almost every area of metaphysics, epistemology, aesthetics and morality. |
| 13886 | Later Frege held that definitions must fix a function's value for every possible argument [Frege, by Wright,C] |
| Full Idea: Frege later became fastidious about definitions, and demanded that they must provide for every possible case, and that no function is properly determined unless its value is fixed for every conceivable object as argument. | |
| From: report of Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903]) by Crispin Wright - Frege's Concept of Numbers as Objects 3.xiv | |
| A reaction: Presumably definitions come in degrees of completeness, but it seems harsh to describe a desire for the perfect definition as 'fastidious', especially if we are talking about mathematics, rather than defining 'happiness'. |
| 9845 | We can't define a word by defining an expression containing it, as the remaining parts are a problem [Frege] |
| Full Idea: Given the reference (bedeutung) of an expression and a part of it, obviously the reference of the remaining part is not always determined. So we may not define a symbol or word by defining an expression in which it occurs, whose remaining parts are known | |
| From: Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903], §66) | |
| A reaction: Dummett cites this as Frege's rejection of contextual definitions, which he had employed in the Grundlagen. I take it not so much that they are wrong, as that Frege decided to set the bar a bit higher. |
| 10019 | Only what is logically complex can be defined; what is simple must be pointed to [Frege] |
| Full Idea: Only what is logically complex can be defined; what is simple can only be pointed to. | |
| From: Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903], §180), quoted by Harold Hodes - Logicism and Ontological Commits. of Arithmetic p.137 | |
| A reaction: Frege presumably has in mind his treasured abstract objects, such as cardinal numbers. It is hard to see how you could 'point to' anything in the phenomenal world that had atomic simplicity. Hodes calls this a 'desperate Kantian move'. |
| 2345 | Semantic notions do not occur in Tarski's definitions, but assessing their correctness involves translation [Putnam] |
| Full Idea: Although no semantic notions are used in Tarski's truth definitions themselves, they are used in deciding when such a definition is correct, namely the notion of translation. | |
| From: Hilary Putnam (Representation and Reality [1988], §4 p.66) |
| 2347 | Asserting the truth of an indexical statement is not the same as uttering the statement [Putnam] |
| Full Idea: If you say "I am going to drive this car", and I say "That's true", that is very different from my saying "I am going to drive this car". | |
| From: Hilary Putnam (Representation and Reality [1988], §4 p.68) |
| 9886 | Cardinals say how many, and reals give measurements compared to a unit quantity [Frege] |
| Full Idea: The cardinals and the reals are completely disjoint domains. The cardinal numbers answer the question 'How many objects of a given kind are there?', but the real numbers are for measurement, saying how large a quantity is compared to a unit quantity. | |
| From: Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903], §157), quoted by Michael Dummett - Frege philosophy of mathematics Ch.19 | |
| A reaction: We might say that cardinals are digital and reals are analogue. Frege is unusual in totally separating them. They map onto one another, after all. Cardinals look like special cases of reals. Reals are dreams about the gaps between cardinals. |
| 9889 | Real numbers are ratios of quantities [Frege, by Dummett] |
| Full Idea: Frege fixed on construing real numbers as ratios of quantities (in agreement with Newton). | |
| From: report of Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903]) by Michael Dummett - Frege philosophy of mathematics Ch.20 | |
| A reaction: If 3/4 is the same real number as 6/8, which is the correct ratio? Why doesn't the square root of 9/16 also express it? Why should irrationals be so utterly different from rationals? In what sense are they both 'numbers'? |
| 10553 | A number is a class of classes of the same cardinality [Frege, by Dummett] |
| Full Idea: For Frege, in 'Grundgesetze', a number is a class of classes of the same cardinality. | |
| From: report of Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903]) by Michael Dummett - Frege Philosophy of Language (2nd ed) Ch.14 |
| 10020 | Frege's biggest error is in not accounting for the senses of number terms [Hodes on Frege] |
| Full Idea: The inconsistency of Grundgesetze was only a minor flaw. Its fundamental flaw was its inability to account for the way in which the senses of number terms are determined. It leaves the reference-magnetic nature of the standard numberer a mystery. | |
| From: comment on Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903]) by Harold Hodes - Logicism and Ontological Commits. of Arithmetic p.139 | |
| A reaction: A point also made by Hofweber. As a logician, Frege was only concerned with the inferential role of number terms, and he felt he had captured their logical form, but it is when you come to look at numbers in natural language that he seem in trouble. |
| 9887 | Formalism misunderstands applications, metatheory, and infinity [Frege, by Dummett] |
| Full Idea: Frege's three main objections to radical formalism are that it cannot account for the application of mathematics, that it confuses a formal theory with its metatheory, and it cannot explain an infinite sequence. | |
| From: report of Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903], §86-137) by Michael Dummett - Frege philosophy of mathematics | |
| A reaction: The application is because we don't design maths randomly, but to be useful. The third objection might be dealt with by potential infinities (from formal rules). The second objection sounds promising. |
| 8751 | Only applicability raises arithmetic from a game to a science [Frege] |
| Full Idea: It is applicability alone which elevates arithmetic from a game to the rank of a science. | |
| From: Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903], §91), quoted by Stewart Shapiro - Thinking About Mathematics 6.1.2 | |
| A reaction: This is the basic objection to Formalism. It invites the question of why it is applicable, which platonists like Frege don't seem to answer (though Plato himself has reality modelled on the Forms). This is why I like structuralism. |
| 2349 | Realists believe truth is correspondence, independent of humans, is bivalent, and is unique [Putnam] |
| Full Idea: Metaphysical realism about truth is a bundle of ideas: that it is a matter of Correspondence, that it exhibits Independence (of humans), Bivalence, and Uniqueness (there is only one ultimate truth). | |
| From: Hilary Putnam (Representation and Reality [1988], §7 p.107) | |
| A reaction: It requires robust truth, but not correspondence (which is too strict, and too imprecise). Not sure about bivalence, which seems an unwarranted imposition. The other two seem fine, to me. |
| 2351 | Aristotle says an object (e.g. a lamp) has identity if its parts stay together when it is moved [Putnam] |
| Full Idea: The parts of a lamp stay together when it is moved (which is one of Aristotle's criteria for objecthood). | |
| From: Hilary Putnam (Representation and Reality [1988], §7 p.110) | |
| A reaction: Metaphysics 1052a26 (just after the cross-reference) says a thing may be unified 'if its movement is single'. |
| 9891 | The first demand of logic is of a sharp boundary [Frege] |
| Full Idea: The first demand of logic is of a sharp boundary. | |
| From: Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903], §160), quoted by Michael Dummett - Frege philosophy of mathematics Ch.22 | |
| A reaction: Nothing I have read about vagueness has made me doubt Frege's view of this, although precisification might allow you to do logic with vague concepts without having to finally settle where the actual boundaries are. |
| 2331 | Functionalism says robots and people are the same at one level of abstraction [Putnam] |
| Full Idea: My "functionalism" insisted that a robot, a human being, a silicon creature and a disembodied spirit could all work much the same way when described at the relevant level of abstraction, and it is wrong to think the essence of mind is hardware. | |
| From: Hilary Putnam (Representation and Reality [1988], Int p.xii) | |
| A reaction: This is the key point about the theory - that it is an abstract theory of mind, saying nothing about substances. It drew, however, some misguided criticisms suggesting silly implementations. |
| 2348 | Is there just one computational state for each specific belief? [Putnam] |
| Full Idea: The idea that there is one computational state that every being who believes that there are lots of cats in the neighbourhood is in must be false. | |
| From: Hilary Putnam (Representation and Reality [1988], §5 p.84) | |
| A reaction: It is tempting to say that the mental states of such people must have SOMETHING in common, until you realise that all you can specify is that all their states are about cats. |
| 2332 | Functionalism can't explain reference and truth, which are needed for logic [Putnam] |
| Full Idea: Functionalism has as much trouble with physical accounts of reference as of meaning. Reference is the main tool used in formal theories of truth. But 'truth' isn't folk psychology, it is central to logic, which everyone wants. | |
| From: Hilary Putnam (Representation and Reality [1988], Int p.xiv) | |
| A reaction: All logic is defined in terms of truth and falsehood resulting from reasoning, but it could be that 'true' and 'false' have no more content that 1 and 0 in binary electronics. They are distinct, but empty. |
| 2071 | If concepts have external meaning, computational states won't explain psychology [Putnam] |
| Full Idea: Computational models of the brain/mind will not suffice for cognitive psychology. We cannot individuate concepts and beliefs without reference to the environment. Meanings aren't "in the head". | |
| From: Hilary Putnam (Representation and Reality [1988], p.73) | |
| A reaction: Mr Functionalism quits! |
| 2344 | If we are going to eliminate folk psychology, we must also eliminate folk logic [Putnam] |
| Full Idea: Why don't the eliminationists speak of "folk logic" as well as "folk psychology"? | |
| From: Hilary Putnam (Representation and Reality [1988], §4 p.60) | |
| A reaction: I think Putnam considers that if you can prove 'truth' to be a necessary feature of mental life, that connects mind and world, but marking a sentence as 'T' doesn't make any connections. |
| 2074 | Can we give a scientific, computational account of folk psychology? [Putnam] |
| Full Idea: The desire that grips Fodor, as it once gripped me, is the desire to make belief-desire psychology "scientific" by simply identifying it outright with computational psychology. | |
| From: Hilary Putnam (Representation and Reality [1988], p.7) | |
| A reaction: An "outright" identification looks very implausible. It seems that we should accept that belief-desire psychology is a very good guide to normal brain events, but a bad guide to unusual brain events. See Ideas 2987 and 7519. |
| 2343 | Reference may be different while mental representation is the same [Putnam] |
| Full Idea: The 'mental representations' of Earth speakers and Twin Earth speakers were not in any way different; the reference was different because the substances were different. Reference is fixed by the environment itself. | |
| From: Hilary Putnam (Representation and Reality [1988], §2 p.32) | |
| A reaction: There seems to be an elementary distinction here between what you think you are referring to, and what you are in fact referring to. "That man is the Prince of Wales" (pointing at the butler). |
| 9890 | The modern account of real numbers detaches a ratio from its geometrical origins [Frege] |
| Full Idea: From geometry we retain the interpretation of a real number as a ratio of quantities or measurement-number; but in more recent times we detach it from geometrical quantities, and from all particular types of quantity. | |
| From: Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903], §159), quoted by Michael Dummett - Frege philosophy of mathematics | |
| A reaction: Dummett glosses the 'recent' version as by Cantor and Dedekind in 1872. This use of 'detach' seems to me startlingly like the sort of psychological abstractionism which Frege was so desperate to avoid. |
| 11846 | If we abstract the difference between two houses, they don't become the same house [Frege] |
| Full Idea: If abstracting from the difference between my house and my neighbour's, I were to regard both houses as mine, the defect of the abstraction would soon be made clear. It may, though, be possible to obtain a concept by means of abstraction... | |
| From: Gottlob Frege (Grundgesetze der Arithmetik 2 (Basic Laws) [1903], §99) | |
| A reaction: Note the important concession at the end, which shows Frege could never deny the abstraction process, despite all the modern protests by Geach and Dummett that he totally rejected it. |
| 2346 | Meaning and translation (which are needed to define truth) both presuppose the notion of reference [Putnam] |
| Full Idea: The notion of meaning, and hence of translation (needed to define truth), presupposes the notion of reference. | |
| From: Hilary Putnam (Representation and Reality [1988], §4 p.67) | |
| A reaction: It is plausible to see reference as the fundamental notion of language. With no anchors in reality, language would be 'private', in LW's sense. |
| 2354 | "Meaning is use" is not a definition of meaning [Putnam] |
| Full Idea: "Meaning is use" is not a definition of meaning. | |
| From: Hilary Putnam (Representation and Reality [1988], §7 p.119) | |
| A reaction: I agree. It probably fails to define meaning because it is false. A corkscrew is not the action of opening a wine bottle. |
| 2334 | Meaning holism tried to show that you can't get fixed meanings built out of observation terms [Putnam] |
| Full Idea: The doctrine of Quine called "meaning holism" offered arguments refuting logical positivist attempts to show that every term we can understand can be defined using a limited group of "observation terms". | |
| From: Hilary Putnam (Representation and Reality [1988], §1 p.08) | |
| A reaction: To seems a rather large jump from saying that sentences come in groups to full-blown 'holism' (involving every sentence). |
| 2335 | Understanding a sentence involves background knowledge and can't be done in isolation [Putnam] |
| Full Idea: If I say "Hawks fly", I do not intend my hearer to deduce that a hawk with a broken wing will fly. What we expect depends on the whole network of belief. Language describes experience as a network, not sentence by sentence. | |
| From: Hilary Putnam (Representation and Reality [1988], §1 p.09) | |
| A reaction: The shortcut through this is 'exactly what did you mean when you said "Hawks fly"?'. That is, get me closer to your proposition. |
| 2336 | Holism seems to make fixed definition more or less impossible [Putnam] |
| Full Idea: Holism immediately suggests that most terms cannot be defined, at least not in a way that is fixed once and for all. | |
| From: Hilary Putnam (Representation and Reality [1988], §1 p.09) | |
| A reaction: Perhaps there exists a single perfect definition for each holistic system, only graspable by a transcendent intellect. Or why can't there be a matching holistic system of definitions? |
| 2340 | We should separate how the reference of 'gold' is fixed from its conceptual content [Putnam] |
| Full Idea: The effect of my account, as of Kripke's, is to separate the question of how the reference of terms such as 'gold' is fixed from the question of their conceptual content. | |
| From: Hilary Putnam (Representation and Reality [1988], §2 p.38) | |
| A reaction: Too simple. 'Gold' isn't a proper name, like 'Hilary', which needs no more content than a serial number. Baptising a gold sample needs much more information than baptising a person. |
| 2341 | Like names, natural kind terms have their meaning fixed by extension and reference [Putnam] |
| Full Idea: It seems that the dominant "component" of natural kind words is the extension. The referential factor does almost all the work, and natural kind terms resemble names. | |
| From: Hilary Putnam (Representation and Reality [1988], §3 p.49) | |
| A reaction: My concept of 'tiger' does not mainly consist of the tigers. Does the concept contract as the tiger population dwindles? Prototypes, exemplars etc. See 'Concepts' |
| 2339 | Aristotle implies that we have the complete concepts of a language in our heads, but we don't [Putnam] |
| Full Idea: What is wrong with the Aristotelian picture (of meaning and reference based on concepts) is that it suggest that everything that is necessary for the use of language is stored in each individual mind, but no individual language works this way. | |
| From: Hilary Putnam (Representation and Reality [1988], §2 p.25) | |
| A reaction: Languages must partly work that way. You can't talk without a conceptual storehouse. In a small society I would expect every adult to know the full vocabulary. |
| 2338 | Reference (say to 'elms') is a social phenomenon which we can leave to experts [Putnam] |
| Full Idea: Reference is a social phenomenon. Individual speakers do not have to know how to distinguish robins, or elms, or aluminium. They can always rely on experts to do this for them. | |
| From: Hilary Putnam (Representation and Reality [1988], §2 p.22) | |
| A reaction: It can't just be a social phenomenon. The experts don't just enquire about standard usage, or defer to Hilary Putnam. |
| 19216 | Propositions (such as 'that dog is barking') only exist if their items exist [Williamson] |
| Full Idea: A proposition about an item exists only if that item exists... how could something be the proposition that that dog is barking in circumstances in which that dog does not exist? | |
| From: Timothy Williamson (Necessary Existents [2002], p.240), quoted by Trenton Merricks - Propositions | |
| A reaction: This is a view of propositions I can't make sense of. If I'm under an illusion that there is a dog barking nearby, when there isn't one, can I not say 'that dog is barking'? If I haven't expressed a proposition, what have I done? |
| 2342 | "Water" is a natural kind term, but "H2O" is a description [Putnam] |
| Full Idea: "Water" functions as a natural kind term, but "H2O" is a description, synonymous with an account of its atoms. | |
| From: Hilary Putnam (Representation and Reality [1988], §3 p.50) |