17 ideas
5831 | The new view is that "water" is a name, and has no definition [Schwartz,SP] |
Full Idea: Perhaps the modern view is best expressed as saying that "water" has no definition at all, at least in the traditional sense, and is a proper name of a specific substance. | |
From: Stephen P. Schwartz (Intro to Naming,Necessity and Natural Kinds [1977], §III) | |
A reaction: This assumes that proper names have no definitions, though I am not clear how we can grasp the name 'Aristotle' without some association of properties (human, for example) to go with it. We need a definition of 'definition'. |
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) |
5829 | We refer to Thales successfully by name, even if all descriptions of him are false [Schwartz,SP] |
Full Idea: We can refer to Thales by using the name "Thales" even though perhaps the only description we can supply is false of him. | |
From: Stephen P. Schwartz (Intro to Naming,Necessity and Natural Kinds [1977], §III) | |
A reaction: It is not clear what we would be referring to if all of our descriptions (even 'Greek philosopher') were false. If an archaeologist finds just a scrap of stone with a name written on it, that is hardly a sufficient basis for successful reference. |
5830 | The traditional theory of names says some of the descriptions must be correct [Schwartz,SP] |
Full Idea: The traditional theory of proper names entails that at least some combination of the things ordinarily believed of Aristotle are necessarily true of him. | |
From: Stephen P. Schwartz (Intro to Naming,Necessity and Natural Kinds [1977], §III) | |
A reaction: Searle endorses this traditional theory. Kripke and co. tried to dismiss it, but you can't. If all descriptions of Aristotle turned out to be false (it was actually the name of a Persian statue), our modern references would have been unsuccessful. |
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. |
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. |
21515 | Incoherence may be more important for enquiry than coherence [Olsson] |
Full Idea: While coherence may lack the positive role many have assigned to it, ...incoherence plays an important negative role in our enquiries. | |
From: Erik J. Olsson (Against Coherence [2005], 10.1) | |
A reaction: [He cites Peirce as the main source for this idea] We can hardly by deeply impressed by incoherence if we have no sense of coherence. Incoherence is just one of many markers for theory failure. Missing the target, bad concepts... |
21514 | Coherence is the capacity to answer objections [Olsson] |
Full Idea: According to Lehrer, coherence should be understood in terms of the capacity to answer objections. | |
From: Erik J. Olsson (Against Coherence [2005], 9) | |
A reaction: [Keith Lehrer 1990] We can connect this with the Greek requirement of being able to give an account [logos], which is the hallmark of understanding. I take coherence to be the best method of achieving understanding. Any understanding meets Lehrer's test. |
21496 | Mere agreement of testimonies is not enough to make truth very likely [Olsson] |
Full Idea: Far from guaranteeing a high likelihood of truth by itself, testimonial agreement can apparently do so only if the circumstances are favourable as regards independence, prior probability, and individual credibility. | |
From: Erik J. Olsson (Against Coherence [2005], 1) | |
A reaction: This is Olson's main thesis. His targets are C.I.Lewis and Bonjour, who hoped that a mere consensus of evidence would increase verisimilitude. I don't see a problem for coherence in general, since his favourable circumstances are part of it. |
21499 | Coherence is only needed if the information sources are not fully reliable [Olsson] |
Full Idea: An enquirer who is fortunate enough to have at his or her disposal fully reliable information sources has no use for coherence, the need for which arises only in the context of less than fully reliable informations sources. | |
From: Erik J. Olsson (Against Coherence [2005], 2.6.2) | |
A reaction: I take this to be entirely false. How do you assess reliability? 'I've seen it with my own eyes'. Why trust your eyes? In what visibility conditions do you begin to doubt your eyes? Why do rational people mistrust their intuitions? |
21502 | A purely coherent theory cannot be true of the world without some contact with the world [Olsson] |
Full Idea: The Input Objection says a pure coherence theory would seem to allow that a system of beliefs be justified in spite of being utterly out of contact with the world it purports to describe, so long as it is, to a sufficient extent, coherent. | |
From: Erik J. Olsson (Against Coherence [2005], 4.1) | |
A reaction: Olson seems impressed by this objection, but I don't see how a system could be coherently about the world if it had no known contact with the world. Olson seems to ignore meta-coherence, which evaluates the status of the system being studied. |
21512 | Extending a system makes it less probable, so extending coherence can't make it more probable [Olsson] |
Full Idea: Any non-trivial extension of a belief system is less probable than the original system, but there are extensions that are more coherent than the original system. Hence more coherence does not imply a higher probability. | |
From: Erik J. Olsson (Against Coherence [2005], 6.4) | |
A reaction: [Olson cites Klein and Warfield 1994; compressed] The example rightly says the extension could have high internal coherence, but not whether the extension is coherent with the system being extended. |
5826 | The intension of "lemon" is the conjunction of properties associated with it [Schwartz,SP] |
Full Idea: The conjunction of properties associated with a term such as "lemon" is often called the intension of the term "lemon". | |
From: Stephen P. Schwartz (Intro to Naming,Necessity and Natural Kinds [1977], §II) | |
A reaction: The extension of "lemon" is the set of all lemons. At last, a clear explanation of the word 'intension'! The debate becomes clear - over whether the terms of a language are used in reference to ideas of properties (and substances?), or to external items. |