33 ideas
| 15169 | Metaphysics is clarifying how we speak and think (and possibly improving it) [Sidelle] |
| Full Idea: Metaphysics, for the conventionalist, is not a matter of trying to see deeply into the structure of mind-independent reality, but of trying to clarify the way we actually speak and think, and perhaps negotiating ways of doing this to our best advantage. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.1) | |
| A reaction: Note that he is still allowing space for 'revisionary' as well as for 'descriptive' metaphysics. I can't wholly accept this, as I really do think we can have some deep insights into reality, but Sidelle is articulating a large part of the truth. |
| 15164 | We seem to base necessities on thought experiments and imagination [Sidelle] |
| Full Idea: Judgments of necessity seem always to be based on thought experiments and appeals to what we can imagine. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.1) | |
| A reaction: That is, the denial of this thing seems inconceivable. I would say that they are also based on coherence. The idea that we can think without imagination is nonsense. |
| 15647 | Truth definitions don't produce a good theory, because they go beyond your current language [Halbach] |
| Full Idea: It is far from clear that a definition of truth can lead to a philosophically satisfactory theory of truth. Tarski's theorem on the undefinability of the truth predicate needs resources beyond those of the language for which it is being defined. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1) | |
| A reaction: The idea is that you need a 'metalanguage' for the definition. If I say 'p' is a true sentence in language 'L', I am not making that observation from within language L. The dream is a theory confined to the object language. |
| 15649 | In semantic theories of truth, the predicate is in an object-language, and the definition in a metalanguage [Halbach] |
| Full Idea: In semantic theories of truth (Tarski or Kripke), a truth predicate is defined for an object-language. This definition is carried out in a metalanguage, which is typically taken to include set theory or another strong theory or expressive language. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1) | |
| A reaction: Presumably the metalanguage includes set theory because that connects it with mathematics, and enables it to be formally rigorous. Tarski showed, in his undefinability theorem, that the meta-language must have increased resources. |
| 15655 | Should axiomatic truth be 'conservative' - not proving anything apart from implications of the axioms? [Halbach] |
| Full Idea: If truth is not explanatory, truth axioms should not allow proof of new theorems not involving the truth predicate. It is hence said that axiomatic truth should be 'conservative' - not implying further sentences beyond what the axioms can prove. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.3) | |
| A reaction: [compressed] |
| 15654 | If truth is defined it can be eliminated, whereas axiomatic truth has various commitments [Halbach] |
| Full Idea: If truth can be explicitly defined, it can be eliminated, whereas an axiomatized notion of truth may bring all kinds of commitments. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.3) | |
| A reaction: The general principle that anything which can be defined can be eliminated (in an abstract theory, presumably, not in nature!) raises interesting questions about how many true theories there are which are all equivalent to one another. |
| 15650 | Axiomatic theories of truth need a weak logical framework, and not a strong metatheory [Halbach] |
| Full Idea: Axiomatic theories of truth can be presented within very weak logical frameworks which require very few resources, and avoid the need for a strong metalanguage and metatheory. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1) |
| 15648 | Instead of a truth definition, add a primitive truth predicate, and axioms for how it works [Halbach] |
| Full Idea: The axiomatic approach does not presuppose that truth can be defined. Instead, a formal language is expanded by a new primitive predicate of truth, and axioms for that predicate are then laid down. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1) | |
| A reaction: Idea 15647 explains why Halbach thinks the definition route is no good. |
| 15656 | Deflationists say truth merely serves to express infinite conjunctions [Halbach] |
| Full Idea: According to many deflationists, truth serves merely the purpose of expressing infinite conjunctions. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.3) | |
| A reaction: That is, it asserts sentences that are too numerous to express individually. It also seems, on a deflationist view, to serve for anaphoric reference to sentences, such as 'what she just said is true'. |
| 15657 | To prove the consistency of set theory, we must go beyond set theory [Halbach] |
| Full Idea: The consistency of set theory cannot be established without assumptions transcending set theory. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 2.1) |
| 15652 | We can use truth instead of ontologically loaded second-order comprehension assumptions about properties [Halbach] |
| Full Idea: The reduction of 2nd-order theories (of properties or sets) to axiomatic theories of truth may be conceived as a form of reductive nominalism, replacing existence assumptions (for comprehension axioms) by ontologically innocent truth assumptions. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.1) | |
| A reaction: I like this very much, as weeding properties out of logic (without weeding them out of the world). So-called properties in logic are too abundant, so there is a misfit with their role in science. |
| 15651 | Instead of saying x has a property, we can say a formula is true of x - as long as we have 'true' [Halbach] |
| Full Idea: Quantification over (certain) properties can be mimicked in a language with a truth predicate by quantifying over formulas. Instead of saying that Tom has the property of being a poor philosopher, we can say 'x is a poor philosopher' is true of Tom. | |
| From: Volker Halbach (Axiomatic Theories of Truth (2005 ver) [2005], 1.1) | |
| A reaction: I love this, and think it is very important. He talks of 'mimicking' properties, but I see it as philosophers mistakenly attributing properties, when actually what they were doing is asserting truths involving certain predicates. |
| 15180 | There doesn't seem to be anything in the actual world that can determine modal facts [Sidelle] |
| Full Idea: Metaphysically, nothing in the actual world seems to be a candidate for determining what is necessarily the case. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.4) | |
| A reaction: I file this under 'Dispositions' to show what is at stake in the debate about dispositional and categorical properties. I take a commitment to dispositions to be a commitment to modal facts about the actual world. |
| 15184 | Causal reference presupposes essentialism if it refers to modally extended entities [Sidelle] |
| Full Idea: Even if the causal theory of reference proper does not presuppose essentialism, it does presuppose essentialism if it is to be an account of reference to modally extended entities. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.6) |
| 15172 | Clearly, essential predications express necessary properties [Sidelle] |
| Full Idea: It is clear, of course, that if there are true essential predications, then they express necessary properties. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.2) | |
| A reaction: I would certainly want to ask whether essences have to be analysed as properties, and also (more boldly) whether there might not be contingent essences. |
| 15181 | Being a deepest explanatory feature is an actual, not a modal property [Sidelle] |
| Full Idea: The property of being a deepest explanatory feature is a nonmodal property: it's an actual property. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.4) | |
| A reaction: I don't accept the existence of properties of the form 'being-F'. The possibility of securing a door may be the deepest explanatory feature of a lock. [To be fair to Sidelle, see context - just for once!] Dispositions are actual. |
| 15173 | That the essence of water is its microstructure is a convention, not a discovery [Sidelle] |
| Full Idea: The necessity to water of whatever is found out to be the water's microstructure is given by convention, and is not something which is discovered. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.2) | |
| A reaction: A powerful point. It shows the authority of science that we accept the microstructure as the essence. The essences of statues and people are definitely not their microstructures. One H2O molecule isn't water. Why not? Macro-properties count too! |
| 15185 | We aren't clear about 'same stuff as this', so a principle of individuation is needed to identify it [Sidelle] |
| Full Idea: Independent of conventions, no definite sense can be given to the notion of 'the same stuff as this'. So reference-fixing must include some principle of individuation to determine the aspects of sameness for the identity referred to. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.6) | |
| A reaction: Is he really saying that we don't understand 'same stuff as this'? Surely animals can manage that, and they are not famous for their conventions. Sidelle has fallen into the sortalist trap, I think. |
| 15175 | Evaluation of de dicto modalities does not depend on the identity of its objects [Sidelle] |
| Full Idea: In the evaluation of de dicto modal statements, whether some possible state of affairs is relevant to its truth does not depend on the identity of its objects, as in 'Necessarily, the President of the USA is male'. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.3) | |
| A reaction: This is a more clear-cut and easy to grasp criterion than most that are on offer. |
| 15032 | Necessary a posteriori is conventional for necessity and nonmodal for a posteriority [Sidelle, by Sider] |
| Full Idea: Sidelle defends conventionalism against a posteriori necessities by 'factoring' a necessary a posteriori truth into an analytic component and a nonmodal component. The modal force then comes from the analytic part, and the a posteriority from the other. | |
| From: report of Alan Sidelle (Necessity, Essence and Individuation [1989]) by Theodore Sider - Writing the Book of the World 12.8 | |
| A reaction: [I note that Sidelle refers, it seems, to the nonmodal component as a 'deep explanatory feature', which is exactly what I take an essence to be]. |
| 15179 | To know empirical necessities, we need empirical facts, plus conventions about which are necessary [Sidelle] |
| Full Idea: What we need to know, in order to know what is empirically necessary, is some empirical fact plus our conventions that tell us which truths are necessary given which empirical facts. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.4) | |
| A reaction: I take this attack on a posteriori necessities to be the most persuasive part of Sidelle's case, but you can't just put all of our truths down to convention. There are stabilities in the world, as well as in our conventions. |
| 15171 | The necessary a posteriori is statements either of identity or of essence [Sidelle] |
| Full Idea: The necessary a posteriori crudely divides into two groups - (synthetic) identity statements (between rigid designators), and statements of essential properties. The latter is either statements of property identity, or of the essences of natural kinds. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.2) | |
| A reaction: He cites Kripke's examples (Hesperus,Cicero,Truman,water,gold), and divides them into the two groups. Helpful. |
| 15167 | Empiricism explores necessities and concept-limits by imagining negations of truths [Sidelle] |
| Full Idea: In the traditional empiricist picture, we go about modal enquiry by trying to see whether we can imagine a situation in which it would be correct to assert the negation of a proposed necessary truth. Thus we can find out the limits of our concepts. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.1) |
| 15177 | Contradictoriness limits what is possible and what is imaginable [Sidelle] |
| Full Idea: Contradictoriness is the boundary both of what is possible and also of what is imaginable. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.4) | |
| A reaction: Of course we may see contradictions where there are none, and fail to grasp real hidden contradictions, so the two do not coincide in the practice. I think I would say it is 'a' boundary, not 'the' boundary. |
| 15176 | The individuals and kinds involved in modality are also a matter of convention [Sidelle] |
| Full Idea: It is not merely the modal facts that result from our conventions, but the individuals and kinds that are modally involved. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.3) | |
| A reaction: I am beginning to find Sidelle's views very sympathetic - going over to the Dark Side, I'm afraid. But conventions won't work at all if they don't correspond closely to reality. |
| 15174 | A thing doesn't need transworld identity prior to rigid reference - that could be a convention of the reference [Sidelle] |
| Full Idea: For a term to be rigid, it is said there must be real transworld identity prior to our use of the rigid term, ..but this may only be because we have conventional principles for individuating across worlds. 'Let's call him Fred' - perhaps explicitly rigid. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.3) | |
| A reaction: This seems right. An example might be a comic book character, who retains a perfect identity in all the comics, with no scars, weight change, or ageing. |
| 15183 | 'Dthat' operates to make a singular term into a rigid term [Sidelle] |
| Full Idea: 'Dthat' is Kaplan's indexical operator; it operates on a given singular term, φ, and makes it into a rigid designator of whatever φ designates in the original context. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.6 n11) | |
| A reaction: I like this idea a lot, because it strikes me that referring to something rigidly is a clear step beyond referring to it in actuality. I refer to 'whoever turns up each week', but that is hardly rigid. The germ of 2-D semantics is here. |
| 15165 | A priori knowledge is entirely of analytic truths [Sidelle] |
| Full Idea: The a priori method yields a priori knowledge, and the objects of this knowledge are not facts about the world, but analytic truths. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.1) | |
| A reaction: Are we not allowed any insights at all into how the world must be, independent of how we happen to conceptualise it? |
| 15168 | That water is essentially H2O in some way concerns how we use 'water' [Sidelle] |
| Full Idea: If water is essentially H2O, this is going to have something to do with our intentions in using 'water'. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.1) | |
| A reaction: This very simple point looks to be correct, and raises very important questions about the whole Twin Earth thing. When new discoveries are made, words shift their meanings. We're not quite sure what 'jade' means any more. |
| 15166 | Causal reference seems to get directly at the object, thus leaving its nature open [Sidelle] |
| Full Idea: The causal theory of reference appears to give us a way to get at an object while leaving it undetermined what its essence or necessary features might be. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.1) | |
| A reaction: This pinpoints why the direct/causal theory of reference seems to open the doors to scientific essentialism. Sidelle, of course, opposes the whole programme. |
| 15182 | Because some entities overlap, reference must have analytic individuation principles [Sidelle] |
| Full Idea: The phenomenon of overlapping entities requires that if our reference is to be determinate (as determinate as it is), then there must be analytic principles of individuation. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.5) | |
| A reaction: His point is that there is something inescapably conventional about the way in which our reference works. It isn't just some bald realist baptism. |
| 5655 | Happiness is not satisfaction of desires, but fulfilment of values [Bradley, by Scruton] |
| Full Idea: For Bradley, the happiness of the individual is not to be understood in terms of his desires and needs, but rather in terms of his values - which is to say, in terms of those of his desires which he incorporates into his self. | |
| From: report of F.H. Bradley (Ethical Studies [1876]) by Roger Scruton - Short History of Modern Philosophy Ch.16 | |
| A reaction: Good. Bentham will reduce the values to a further set of desires, so that a value is a complex (second-level?) desire. I prefer to think of values as judgements, but I like Scruton's phrase of 'incorporating into his self'. Kant take note (Idea 1452). |
| 15178 | Can anything in science reveal the necessity of what it discovers? [Sidelle] |
| Full Idea: Is there anything in the procedures of scientists that could reveal to them that water is necessarily H2O or that gold necessarily has atomic number 79. | |
| From: Alan Sidelle (Necessity, Essence and Individuation [1989], Ch.4) | |
| A reaction: This is Leibniz's is view, that empirical evidence can never reveal necessities. Given that we know some necessities, you have an argument for rationalism. |