18 ideas
15375 | If terms change their designations in different states, they are functions from states to objects [Fitting] |
Full Idea: The common feature of every designating term is that designation may change from state to state - thus it can be formalized by a function from states to objects. | |
From: Melvin Fitting (Intensional Logic [2007], 3) | |
A reaction: Specifying the objects sounds OK, but specifying states sounds rather tough. |
15376 | Intensional logic adds a second type of quantification, over intensional objects, or individual concepts [Fitting] |
Full Idea: To first order modal logic (with quantification over objects) we can add a second kind of quantification, over intensions. An intensional object, or individual concept, will be modelled by a function from states to objects. | |
From: Melvin Fitting (Intensional Logic [2007], 3.3) |
15378 | Awareness logic adds the restriction of an awareness function to epistemic logic [Fitting] |
Full Idea: Awareness logic enriched Hintikka's epistemic models with an awareness function, mapping each state to the set of formulas we are aware of at that state. This reflects some bound on the resources we can bring to bear. | |
From: Melvin Fitting (Intensional Logic [2007], 3.6.1) | |
A reaction: [He cites Fagin and Halpern 1988 for this] |
15379 | Justication logics make explicit the reasons for mathematical truth in proofs [Fitting] |
Full Idea: In justification logics, the logics of knowledge are extended by making reasons explicit. A logic of proof terms was created, with a semantics. In this, mathematical truths are known for explicit reasons, and these provide a measure of complexity. | |
From: Melvin Fitting (Intensional Logic [2007], 3.6.1) |
11026 | Classical logic is deliberately extensional, in order to model mathematics [Fitting] |
Full Idea: Mathematics is typically extensional throughout (we write 3+2=2+3 despite the two terms having different meanings). ..Classical first-order logic is extensional by design since it primarily evolved to model the reasoning of mathematics. | |
From: Melvin Fitting (Intensional Logic [2007], §1) |
11028 | λ-abstraction disambiguates the scope of modal operators [Fitting] |
Full Idea: λ-abstraction can be used to abstract and disambiguate a predicate. De re is [λx◊P(x)](f) - f has the possible-P property - and de dicto is ◊[λxP(x)](f) - possibly f has the P-property. Also applies to □. | |
From: Melvin Fitting (Intensional Logic [2007], §3.3) | |
A reaction: Compare the Barcan formula. Originated with Church in the 1930s, and Carnap 1947, but revived by Stalnaker and Thomason 1968. Because it refers to the predicate, it has a role in intensional versions of logic, especially modal logic. |
18890 | Putnam smuggles essentialism about liquids into his proof that water must be H2O [Salmon,N on Putnam] |
Full Idea: In the full exposition of Putnam's mechanism for generating the necessary truth that water is H2O, we find that the mechanism employs a certain nontrivial general principle of essentialism concerning liquid substances as a crucial premise. | |
From: comment on Hilary Putnam (The Meaning of 'Meaning' [1975]) by Nathan Salmon - Reference and Essence (1st edn) 6.23.1 | |
A reaction: This charge, that Kripke and Putnam smuggle the essentialism into their semantics, rather than deriving it, is the nub of Salmon's criticism of them. It seems to me that a new world view emerged while those two where revising the semantics. |
15377 | Definite descriptions pick out different objects in different possible worlds [Fitting] |
Full Idea: Definite descriptions pick out different objects in different possible worlds quite naturally. | |
From: Melvin Fitting (Intensional Logic [2007], 3.4) | |
A reaction: A definite description can pick out the same object in another possible world, or a very similar one, or an object which has almost nothing in common with the others. |
7705 | The Twin Earth theory suggests that intentionality is independent of qualia [Jacquette on Putnam] |
Full Idea: Putnam's Twin Earth thought experiment suggests that two thinkers can have identical qualia, despite intending different objects on Earth and Twin Earth, and hence that qualia and intentionality must be logically independent of one another. | |
From: comment on Hilary Putnam (The Meaning of 'Meaning' [1975]) by Dale Jacquette - Ontology Ch.10 | |
A reaction: [See Idea 4099, Idea 3208, Idea 7612 for Twin Earth]. Presumably my thought of 'the smallest prime number above 10000' would be a bit thin on qualia too. Does that make them 'logically' independent? Depends what we reduce qualia or intentionality to. |
4099 | If Twins talking about 'water' and 'XYZ' have different thoughts but identical heads, then thoughts aren't in the head [Putnam, by Crane] |
Full Idea: Putnam claims that the Twins have different thoughts even though their heads are the same, so their thoughts (about 'water' or 'XYZ') cannot be in their heads. | |
From: report of Hilary Putnam (The Meaning of 'Meaning' [1975]) by Tim Crane - Elements of Mind 4.37 | |
A reaction: Is Putnam guilty of a simple confusion of de re and de dicto reference? |
12026 | We say ice and steam are different forms of water, but not that they are different forms of H2O [Forbes,G on Putnam] |
Full Idea: Putnam presumes it is correct to say that ice and steam are forms of water, rather than that ice, water and steam are three forms of H2O. If we allow the latter, then 'water is H2O' is not an identity, but elliptical for 'water is H2O in liquid state'. | |
From: comment on Hilary Putnam (The Meaning of 'Meaning' [1975]) by Graeme Forbes - The Metaphysics of Modality 8.2 | |
A reaction: This nice observation seems to reveal that the word 'water' is ambiguous. I presume the ambiguity preceded the discovery of its chemical construction. Shakespeare would have hesitated over whether to say 'water is ice'. Context would matter. |
3208 | Does 'water' mean a particular substance that was 'dubbed'? [Putnam, by Rey] |
Full Idea: Putnam argued that "water" refers to H2O by virtue of causal chains extending from present use back to early dubbing uses of it that were in fact dubbings of the substance H2O (although, of course, the original users of the word didn't know this). | |
From: report of Hilary Putnam (The Meaning of 'Meaning' [1975]) by Georges Rey - Contemporary Philosophy of Mind 9.2.1 | |
A reaction: This is the basic idea of the Causal Theory of Reference. Nice conclusion: most of us don't know what we are talking about. Maybe the experts on H2O are also wrong... |
3893 | Often reference determines sense, and not (as Frege thought) vice versa [Putnam, by Scruton] |
Full Idea: Putnam argues that, Frege notwithstanding, it is often the case that reference determines sense, and not vice versa. | |
From: report of Hilary Putnam (The Meaning of 'Meaning' [1975]) by Roger Scruton - Modern Philosophy:introduction and survey 19.6 | |
A reaction: Does this say anything more than that once you have established a reference, you can begin to collect information about the referent? |
13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
Full Idea: In a single day there lies open to men of learning more than there ever does to the unenlightened in the longest of lifetimes. | |
From: Posidonius (fragments/reports [c.95 BCE]), quoted by Seneca the Younger - Letters from a Stoic 078 | |
A reaction: These remarks endorsing the infinite superiority of the educated to the uneducated seem to have been popular in late antiquity. It tends to be the religions which discourage great learning, especially in their emphasis on a single book. |
11191 | The hidden structure of a natural kind determines membership in all possible worlds [Putnam] |
Full Idea: If there is a hidden structure, then generally it determines what it is to be a member of the natural kind, ...in all possible worlds. Put another way, it determines what we can and cannot counterfactually suppose about the natural kind. | |
From: Hilary Putnam (The Meaning of 'Meaning' [1975], p.241) | |
A reaction: This is the arrival of the bold new view of natural kinds (which is actually the original view - see Idea 8153). One must be careful of the necessity here. There is causal context, vagueness etc. |
11192 | If causes are the essence of diseases, then disease is an example of a relational essence [Putnam, by Williams,NE] |
Full Idea: Putnam takes causes to be the essence of disease kinds, and they are distinct from the diseases they cause, both in identity and in proper parthood. These are relational properties, so Putnam gives examples of natural kinds with relational essences. | |
From: report of Hilary Putnam (The Meaning of 'Meaning' [1975]) by Neil E. Williams - Putnam's Traditional Neo-Essentialism §4 | |
A reaction: This seems to be a nice point, since scientific essentialism invariable takes itself to be pursuing instrinsic properties when it unravels the essences of natural kinds. Probably the best response is the Putnam has got muddled. |
11190 | Archimedes meant by 'gold' the hidden structure or essence of the stuff [Putnam] |
Full Idea: When Archimedes asserted that something was gold, he was not just saying that it had the superficial characteristics of gold; he was saying that it had the same general hidden structure (the same 'essence', so to speak) as any normal piece of local gold. | |
From: Hilary Putnam (The Meaning of 'Meaning' [1975], p.235) | |
A reaction: This is one of the key announcements of the new scientific essentialism, and seems to me to be totally correct. Obviously Archimedes could say 'this is really gold, even if it no way appears to be gold'. |
20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |
Full Idea: Posidonius defined time thus: it is an interval of motion, or the measure of speed and slowness. | |
From: report of Posidonius (fragments/reports [c.95 BCE]) by John Stobaeus - Anthology 1.08.42 | |
A reaction: Hm. Can we define motion or speed without alluding to time? Looks like we have to define them as a conjoined pair, which means we cannot fully understand either of them. |