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All the ideas for 'works', 'Powers' and 'The Tarskian Turn'

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85 ideas

1. Philosophy / D. Nature of Philosophy / 3. Philosophy Defined
Philosophy is the most general intellectual discipline [Horsten]
     Full Idea: Philosophy is the most general intellectual discipline.
     From: Leon Horsten (The Tarskian Turn [2011], 05.1)
     A reaction: Very simple, but exactly how I see the subject. It is continuous with the sciences, and tries to give an account of nature, but operating at an extreme level of generality. It must respect the findings of science, but offer bold interpretations.
1. Philosophy / E. Nature of Metaphysics / 1. Nature of Metaphysics
Substantive metaphysics says what a property is, not what a predicate means [Molnar]
     Full Idea: The motto of what is presented here is 'less conceptual analysis, more metaphysics', where the distinction is equivalent to the distinction between saying what 'F' means and saying what being F is.
     From: George Molnar (Powers [1998], 1.1)
     A reaction: This seems to me to capture exactly the spirit of metaphysics since Saul Kripke's work, though some people engaged in it seem to me to be trapped in an outdated linguistic view of the matter. Molnar credits Locke as the source of his view.
2. Reason / D. Definition / 2. Aims of Definition
A definition should allow the defined term to be eliminated [Horsten]
     Full Idea: A definition allows a defined term to be eliminated in every context in which it appears.
     From: Leon Horsten (The Tarskian Turn [2011], 04.2)
     A reaction: To do that, a definition had better be incredibly comprehensive, so that no nice nuance of the original term is thrown out.
2. Reason / D. Definition / 4. Real Definition
A real definition gives all the properties that constitute an identity [Molnar]
     Full Idea: A real definition expresses the sum of the properties that constitute the identity of the thing defined.
     From: George Molnar (Powers [1998], 1.4.4)
     A reaction: This is a standard modern view among modern essentialists, and one which I believe can come into question. It seems to miss out the fact that an essence will also explain the possible functions and behaviours of a thing. Explanation seems basic.
3. Truth / A. Truth Problems / 1. Truth
Semantic theories of truth seek models; axiomatic (syntactic) theories seek logical principles [Horsten]
     Full Idea: There are semantical theories of truth, concerned with models for languages containing the truth predicate, and axiomatic (or syntactic) theories, interested in basic logical principles governing the concept of truth.
     From: Leon Horsten (The Tarskian Turn [2011], 01.1)
     A reaction: This is the map of contemporary debates, which seem now to have given up talking about 'correspondence', 'coherence' etc.
Truth is a property, because the truth predicate has an extension [Horsten]
     Full Idea: I take truth to be a property because the truth predicate has an extension - the collection of all true sentences - and this collection does not (unlike the 'extension' of 'exists') consist of everything, or even of all sentences.
     From: Leon Horsten (The Tarskian Turn [2011], 01.1)
     A reaction: He concedes that it may be an 'uninteresting' property. My problem is always that I am unconvinced that truth is tied to sentences. I can make perfect sense of animal thoughts being right or wrong. Extension of mental propositions?
3. Truth / A. Truth Problems / 2. Defining Truth
Truth has no 'nature', but we should try to describe its behaviour in inferences [Horsten]
     Full Idea: We should not aim at describing the nature of truth because there is no such thing. Rather, we should aim at describing the inferential behaviour of truth.
     From: Leon Horsten (The Tarskian Turn [2011], 10.2.3)
3. Truth / A. Truth Problems / 5. Truth Bearers
Propositions have sentence-like structures, so it matters little which bears the truth [Horsten]
     Full Idea: It makes little difference, at least in extensional contexts, whether the truth bearers are propositions or sentences (or assertions). Even if the bearers are propositions rather than sentences, propositions are structured rather like sentences.
     From: Leon Horsten (The Tarskian Turn [2011], 02.4)
     A reaction: The 'extensional' context means you are only talking about the things that are referred to, and not about the way this is expressed. I prefer propositions, but this is an interesting point.
3. Truth / C. Correspondence Truth / 2. Correspondence to Facts
Modern correspondence is said to be with the facts, not with true propositions [Horsten]
     Full Idea: Modern correspondence theorists no longer take things to correspond to true propositions; they consider facts to be the truthmakers of propositions.
     From: Leon Horsten (The Tarskian Turn [2011], 02.1)
     A reaction: If we then define facts as the way certain things are, independently from our thinking about it, at least we seem to be avoiding circularity. Not much point in correspondence accounts if you are not a robust realist (like me). [14,000th idea, 23/4/12!]
3. Truth / C. Correspondence Truth / 3. Correspondence Truth critique
The correspondence 'theory' is too vague - about both 'correspondence' and 'facts' [Horsten]
     Full Idea: The principle difficulty of the correspondence theory of truth is its vagueness. It is too vague to be called a theory until more information is given about what is meant by the terms 'correspondence' and 'fact'. Facts can involve a heavy ontology.
     From: Leon Horsten (The Tarskian Turn [2011], 02.1)
     A reaction: I see nothing here to make me give up my commitment to the correspondence view of truth, though it sounds as if I will have to give up the word 'theory' in that context. Truth is so obviously about thought fitting reality that there is nothing to discuss.
3. Truth / D. Coherence Truth / 2. Coherence Truth Critique
The coherence theory allows multiple coherent wholes, which could contradict one another [Horsten]
     Full Idea: The coherence theory seems too liberal. It seems there can be more than one systematic whole which, while being internally coherent, contradict each other, and thus cannot all be true. Coherence is a necessary but not sufficient condition for truth.
     From: Leon Horsten (The Tarskian Turn [2011], 02.1)
     A reaction: This is a modern post-Tarski axiomatic truth theorist making very short work indeed of the coherence theory of truth. I take Horsten to be correct.
3. Truth / E. Pragmatic Truth / 1. Pragmatic Truth
The pragmatic theory of truth is relative; useful for group A can be useless for group B [Horsten]
     Full Idea: The pragmatic theory is unsatisfactory because usefulness is a relative notion. One theory can be useful to group A while being thoroughly impractical for group B. This would make the theory both truth and false.
     From: Leon Horsten (The Tarskian Turn [2011], 02.1)
     A reaction: This objection, along with the obvious fact that certain falsehoods can be very useful, would seem to rule pragmatism out as a theory of truth. It is, in fact, an abandonment of truth.
3. Truth / F. Semantic Truth / 1. Tarski's Truth / a. Tarski's truth definition
Tarski's hierarchy lacks uniform truth, and depends on contingent factors [Horsten]
     Full Idea: According to the Tarskian hierarchical conception, truth is not a uniform notion. ...Also Kripke has emphasised that the level of a token of the truth predicate can depend on contingent factors, such as what else has been said by a speaker.
     From: Leon Horsten (The Tarskian Turn [2011], 04.5)
Tarski Bi-conditional: if you'll assert φ you'll assert φ-is-true - and also vice versa [Horsten]
     Full Idea: The axiom schema 'Sentence "phi;" is true iff φ' is the (unrestricted) Tarski-Biconditional, and is motivated by the thought that if you are willing to assume or outright assert that φ, you will assert that φ is true - and also vice versa.
     From: Leon Horsten (The Tarskian Turn [2011], 02.2)
     A reaction: Very helpful! Most people are just bewildered by the Tarski bi-conditional ('"Snow is white"...), but this formulation nicely shows its minimal character while showing that it really does say something. It says what truths and truth-claims commit you to.
3. Truth / F. Semantic Truth / 1. Tarski's Truth / c. Meta-language for truth
Semantic theories have a regress problem in describing truth in the languages for the models [Horsten]
     Full Idea: Semantic theories give a class of models with a truth predicate, ...but Tarski taught us that this needs a more encompassing framework than its language...so how is the semantics of the framework expressed? The model route has a regress.
     From: Leon Horsten (The Tarskian Turn [2011], 02.3)
     A reaction: [compressed] So this regress problem, of endless theories of truth going up the hierarchy, is Horsten's main reason for opting for axiomatic theories, which he then tries to strengthen, so that they are not quite so deflated.
3. Truth / G. Axiomatic Truth / 1. Axiomatic Truth
Axiomatic approaches avoid limiting definitions to avoid the truth predicate, and limited sizes of models [Horsten]
     Full Idea: An adequate definition of truth can only be given for the fragment of our language that does not contain the truth predicate. A model can never encompass the whole of the domain of discourse of our language. The axiomatic approach avoids these problems.
     From: Leon Horsten (The Tarskian Turn [2011], 10.1)
Axiomatic approaches to truth avoid the regress problem of semantic theories [Horsten]
     Full Idea: The axiomatic approach to truth does not suffer from the regress problem.
     From: Leon Horsten (The Tarskian Turn [2011], 02.3)
     A reaction: See Idea 15345 for the regress problem. The difficulty then seems to be that axiomatic approaches lack expressive power, so the hunt is on for a set of axioms which will do a decent job. Fun work, if you can cope with it.
An axiomatic theory needs to be of maximal strength, while being natural and sound [Horsten]
     Full Idea: The challenge is to find the arithmetically strongest axiomatical truth theory that is both natural and truth-theoretically sound.
     From: Leon Horsten (The Tarskian Turn [2011], 07.7)
'Reflexive' truth theories allow iterations (it is T that it is T that p) [Horsten]
     Full Idea: A theory of truth is 'reflexive' if it allows us to prove truth-iterations ("It is true that it is true that so-and-so").
     From: Leon Horsten (The Tarskian Turn [2011], 01.4)
A good theory of truth must be compositional (as well as deriving biconditionals) [Horsten]
     Full Idea: Deriving many Tarski-biconditionals is not a sufficient condition for being a good theory of truth. A good theory of truth must in addition do justice to the compositional nature of truth.
     From: Leon Horsten (The Tarskian Turn [2011], 06.1)
The Naďve Theory takes the bi-conditionals as axioms, but it is inconsistent, and allows the Liar [Horsten]
     Full Idea: The Naďve Theory of Truth collects all the Tarski bi-conditionals of a language and takes them as axioms. But no consistent theory extending Peano arithmetic can prove all of them. It is inconsistent, and even formalises the liar paradox.
     From: Leon Horsten (The Tarskian Turn [2011], 03.5.2)
     A reaction: [compressed] This looks to me like the account of truth that Davidson was working with, since he just seemed to be compiling bi-conditionals for tricky cases. (Wrong! He championed the Compositional Theory, Horsten p.71)
Axiomatic theories take truth as primitive, and propose some laws of truth as axioms [Horsten]
     Full Idea: In the axiomatic approach we take the truth predicate to express an irreducible, primitive notion. The meaning of the truth predicate is partially explicated by proposing certain laws of truth as basic principles, as axioms.
     From: Leon Horsten (The Tarskian Turn [2011], 04.2)
     A reaction: Judging by Horsten's book, this is a rather fruitful line of enquiry, but it still seems like a bit of a defeat to take truth as 'primitive'. Presumably you could add some vague notion of correspondence as the background picture.
By adding truth to Peano Arithmetic we increase its power, so truth has mathematical content! [Horsten]
     Full Idea: It is surprising that just by adding to Peano Arithmetic principles concerning the notion of truth, we increase the mathematical strength of PA. So, contrary to expectations, the 'philosophical' notion of truth has real mathematical content.
     From: Leon Horsten (The Tarskian Turn [2011], 06.4)
     A reaction: Horsten invites us to be really boggled by this. All of this is in the Compositional Theory TC. It enables a proof of the consistency of arithmetic (but still won't escape Gödel's Second).
3. Truth / G. Axiomatic Truth / 2. FS Truth Axioms
Friedman-Sheard theory keeps classical logic and aims for maximum strength [Horsten]
     Full Idea: The Friedman-Sheard theory of truth holds onto classical logic and tries to construct a theory that is as strong as possible.
     From: Leon Horsten (The Tarskian Turn [2011], 01.4)
3. Truth / G. Axiomatic Truth / 3. KF Truth Axioms
Kripke-Feferman has truth gaps, instead of classical logic, and aims for maximum strength [Horsten]
     Full Idea: If we abandon classical logic in favour of truth-value gaps and try to strengthen the theory, this leads to the Kripke-Feferman theory of truth, and variants of it.
     From: Leon Horsten (The Tarskian Turn [2011], 01.4)
3. Truth / H. Deflationary Truth / 2. Deflationary Truth
Inferential deflationism says truth has no essence because no unrestricted logic governs the concept [Horsten]
     Full Idea: According to 'inferential deflationism', truth is a concept without a nature or an essence. This is betrayed by the fact that there are no unrestricted logical laws that govern the concept of truth.
     From: Leon Horsten (The Tarskian Turn [2011], 01.1)
Deflationism skips definitions and models, and offers just accounts of basic laws of truth [Horsten]
     Full Idea: Contemporary deflationism about truth does not attempt to define truth, and does not rely on models containing the truth predicate. Instead they are interpretations of axiomatic theories of truth, containing only basic laws of truth.
     From: Leon Horsten (The Tarskian Turn [2011], 02.3)
Deflationism concerns the nature and role of truth, but not its laws [Horsten]
     Full Idea: Deflationism is not a theory of the laws of truth. It is a view on the nature and role of the concept of truth.
     From: Leon Horsten (The Tarskian Turn [2011], 05 Intro)
This deflationary account says truth has a role in generality, and in inference [Horsten]
     Full Idea: On the conception of deflationism developed in this book, the prime positive role of the truth predicate is to serve as a device for expressing generalities, and an inferential tool.
     From: Leon Horsten (The Tarskian Turn [2011], 07.5)
Deflationism says truth isn't a topic on its own - it just concerns what is true [Horsten]
     Full Idea: Deflationism says the theory of truth does not have a substantial domain of its own. The domain of the theory of truth consists of the bearers of truth.
     From: Leon Horsten (The Tarskian Turn [2011], 05.1)
     A reaction: The immediate thought is that truth also concerns falsehoods, which would be inexplicable without it. If physics just concerns the physical, does that mean that physics lacks its own 'domain'? Generalising about the truths is a topic.
Deflation: instead of asserting a sentence, we can treat it as an object with the truth-property [Horsten]
     Full Idea: The Deflationary view just says that instead of asserting a sentence, we can turn the sentence into an object and assert that this object has the property of truth.
     From: Leon Horsten (The Tarskian Turn [2011], 05.2.2)
     A reaction: That seems to leave a big question hanging, which concerns the nature of the property that is being attributed to this object. Quine 1970:10-13 says it is just a 'device'. Surely you can rest content with that as an account of truth?
4. Formal Logic / E. Nonclassical Logics / 1. Nonclassical Logics
Nonclassical may accept T/F but deny applicability, or it may deny just T or F as well [Horsten]
     Full Idea: Some nonclassical logic stays close to classical, assuming two mutually exclusive truth values T and F, but some sentences fail to have one. Others have further truth values such as 'half truth', or dialethists allow some T and F at the same time.
     From: Leon Horsten (The Tarskian Turn [2011], 01.2)
     A reaction: I take that to say that the first lot accept bivalence but reject excluded middle (allowing 'truth value gaps'), while the second lot reject both. Bivalence gives the values available, and excluded middle says what has them.
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
Doubt is thrown on classical logic by the way it so easily produces the liar paradox [Horsten]
     Full Idea: Aside from logic, so little is needed to generate the liar paradox that one wonders whether the laws of classical logic are unrestrictedly valid after all. (Many theories of truth have therefore been formulated in nonclassical logic.)
     From: Leon Horsten (The Tarskian Turn [2011], 01.2)
     A reaction: Kripke uses Strong Kleene logic for his theory. The implication is that debates discussed by Horsten actually have the status of classical logic at stake, as well as the nature of truth.
5. Theory of Logic / B. Logical Consequence / 5. Modus Ponens
Deduction Theorem: ψ only derivable from φ iff φ→ψ are axioms [Horsten]
     Full Idea: The Deduction Theorem says ψ is derivable in classical predicate logic from ψ iff the sentence φ→ψ is a theorem of classical logic. Hence inferring φ to ψ is truth-preserving iff the axiom scheme φ→ψ is provable.
     From: Leon Horsten (The Tarskian Turn [2011], 02.2)
     A reaction: Horsten offers this to show that the Tarski bi-conditionals can themselves be justified, and not just the rule of inference involved. Apparently you can only derive something if you first announce that you have the ability to derive it. Odd.
5. Theory of Logic / E. Structures of Logic / 8. Theories in Logic
A theory is 'non-conservative' if it facilitates new mathematical proofs [Horsten]
     Full Idea: A theory is 'non-conservative' if it allows us to prove mathematical facts that go beyond what the background mathematical theory can prove on its own.
     From: Leon Horsten (The Tarskian Turn [2011], 01.4)
     A reaction: This is an instance of the relationship with mathematics being used as the test case for explorations of logic. It is a standard research method, because it is so precise, but should not be mistaken for the last word about a theory.
5. Theory of Logic / G. Quantification / 2. Domain of Quantification
De Morgan introduced a 'universe of discourse', to replace Boole's universe of 'all things' [De Morgan, by Walicki]
     Full Idea: In 1846 De Morgan introduced the enormously influential notion of a possibly arbitrary and stipulated 'universe of discourse'. It replaced Boole's original - and metaphysically a bit suspect - universe of 'all things'.
     From: report of Augustus De Morgan (works [1846]) by Michal Walicki - Introduction to Mathematical Logic History D.1.1
     A reaction: This not only brings formal logic under control, but also reflects normal talk, because there is always an explicit or implicit domain of discourse when we talk. Of virtually any conversation, you can say what it is 'about'.
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
It is easier to imagine truth-value gaps (for the Liar, say) than for truth-value gluts (both T and F) [Horsten]
     Full Idea: It is easier to imagine what it is like for a sentence to lack a truth value than what it is like for a sentence to be both truth and false. So I am grudgingly willing to entertain the possibility that certain sentences (like the Liar) lack a truth value.
     From: Leon Horsten (The Tarskian Turn [2011], 02.5)
     A reaction: Fans of truth value gluts are dialethists like Graham Priest. I'm with Horsten on this one. But in what way can a sentence be meaningful if it lacks a truth-value? He mentions unfulfilled presuppositions and indicative conditionals as gappy.
5. Theory of Logic / I. Semantics of Logic / 4. Satisfaction
Satisfaction is a primitive notion, and very liable to semantical paradoxes [Horsten]
     Full Idea: Satisfaction is a more primitive notion than truth, and it is even more susceptible to semantical paradoxes than the truth predicate.
     From: Leon Horsten (The Tarskian Turn [2011], 06.3)
     A reaction: The Liar is the best known paradox here. Tarski bases his account of truth on this primitive notion, so Horsten is pointing out the difficulties.
5. Theory of Logic / K. Features of Logics / 5. Incompleteness
The first incompleteness theorem means that consistency does not entail soundness [Horsten]
     Full Idea: It is a lesson of the first incompleteness theorem that consistency does not entail soundness. If we add the negation of the gödel sentence for PA as an extra axiom to PA, the result is consistent. This negation is false, so the theory is unsound.
     From: Leon Horsten (The Tarskian Turn [2011], 04.3)
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / a. The Liar paradox
Strengthened Liar: 'this sentence is not true in any context' - in no context can this be evaluated [Horsten]
     Full Idea: The Strengthened Liar sentence says 'this sentence is not true in any context'. It is not hard to figure out that there is no context in which the sentence can be coherently evaluated.
     From: Leon Horsten (The Tarskian Turn [2011], 04.6)
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
English expressions are denumerably infinite, but reals are nondenumerable, so many are unnameable [Horsten]
     Full Idea: The number of English expressions is denumerably infinite. But Cantor's theorem can be used to show that there are nondenumerably many real numbers. So not every real number has a (simple or complex name in English).
     From: Leon Horsten (The Tarskian Turn [2011], 06.3)
     A reaction: This really bothers me. Are we supposed to be committed to the existence of entities which are beyond our powers of naming? How precise must naming be? If I say 'pick a random real number', might that potentially name all of them?
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
ZFC showed that the concept of set is mathematical, not logical, because of its existence claims [Horsten]
     Full Idea: One of the strengths of ZFC is that it shows that the concept of set is a mathematical concept. Many originally took it to be a logical concept. But ZFC makes mind-boggling existence claims, which should not follow if it was a logical concept.
     From: Leon Horsten (The Tarskian Turn [2011], 05.2.3)
     A reaction: This suggests that set theory is not just a way of expressing mathematics (see Benacerraf 1965), but that some aspect of mathematics has been revealed by it - maybe even its essential nature.
Set theory is substantial over first-order arithmetic, because it enables new proofs [Horsten]
     Full Idea: The nonconservativeness of set theory over first-order arithmetic has done much to establish set theory as a substantial theory indeed.
     From: Leon Horsten (The Tarskian Turn [2011], 07.5)
     A reaction: Horsten goes on to point out the price paid, which is the whole new ontology which has to be added to the arithmetic. Who cares? It's all fictions anyway!
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / d. Predicativism
Predicativism says mathematical definitions must not include the thing being defined [Horsten]
     Full Idea: Predicativism has it that a mathematical object (such as a set of numbers) cannot be defined by quantifying over a collection that includes that same mathematical object. To do so would be a violation of the vicious circle principle.
     From: Leon Horsten (The Tarskian Turn [2011], 07.7)
     A reaction: In other words, when you define an object you are obliged to predicate something new, and not just recycle the stuff you already have.
7. Existence / C. Structure of Existence / 4. Ontological Dependence
Ontological dependence rests on essential connection, not necessary connection [Molnar]
     Full Idea: Ontological dependence is better understood in terms of an essential connection, rather than simply a necessary connection.
     From: George Molnar (Powers [1998], 1.4.4)
     A reaction: This seems to be an important piece in the essentialist jigsaw. Apart from essentialism, I can't think of any doctrine which offers any sort of explanation of the self-evident fact of certain ontological dependencies.
7. Existence / D. Theories of Reality / 8. Facts / b. Types of fact
We may believe in atomic facts, but surely not complex disjunctive ones? [Horsten]
     Full Idea: While positive and perhaps even negative atomic facts may be unproblematic, it seems excessive to commit oneself to the existence of logically complex facts such as disjunctive facts.
     From: Leon Horsten (The Tarskian Turn [2011], 02.1)
     A reaction: Presumably it is hard to deny that very complex statements involving massive disjunctions can be true or false. But why does commitment to real facts have to involve a huge ontology? The ontology is just the ingredients of the fact, isn't it?
7. Existence / D. Theories of Reality / 10. Vagueness / f. Supervaluation for vagueness
In the supervaluationist account, disjunctions are not determined by their disjuncts [Horsten]
     Full Idea: If 'Britain is large' and 'Italy is large' lack truth values, then so must 'Britain or Italy is large' - so on the supervaluationist account the truth value of a disjunction is not determined by the truth values of its disjuncts.
     From: Leon Horsten (The Tarskian Turn [2011], 06.2)
     A reaction: Compare Idea 15362 to get the full picture here.
If 'Italy is large' lacks truth, so must 'Italy is not large'; but classical logic says it's large or it isn't [Horsten]
     Full Idea: If 'Italy is a large country' lacks a truth value, then so too, presumably, does 'Italy is not a large country'. But 'Italy is or is not a large country' is true, on the supervaluationist account, because it is a truth of classical propositional logic.
     From: Leon Horsten (The Tarskian Turn [2011], 06.2)
     A reaction: See also Idea 15363. He cites Fine 1975.
7. Existence / E. Categories / 3. Proposed Categories
The three categories in ontology are objects, properties and relations [Molnar]
     Full Idea: The ontologically fundamental categories are three in number: Objects, Properties, and Relations.
     From: George Molnar (Powers [1998], 2 Intr)
     A reaction: We need second-order logic to quantify over all of these. The challenge to this view might be that it is static, and needs the addition of processes or events. Molnar rejects facts and states of affairs.
8. Modes of Existence / A. Relations / 4. Formal Relations / a. Types of relation
Reflexive relations are syntactically polyadic but ontologically monadic [Molnar]
     Full Idea: Reflexive relations are, and non-reflexive relations may be, monadic in the ontological sense although they are syntactically polyadic.
     From: George Molnar (Powers [1998], 1.4.5)
     A reaction: I find this a very helpful distinction, as I have never quite understood reflexive relations as 'relations', even in the most obvious cases, such as self-love or self-slaughter.
8. Modes of Existence / B. Properties / 1. Nature of Properties
If atomism is true, then all properties derive from ultimate properties [Molnar]
     Full Idea: If a priori atomism is a true theory of the world, then all properties are derivative from ultimate properties.
     From: George Molnar (Powers [1998], 1.4.1)
     A reaction: Presumably there is a physicalist metaphysic underlying this, which means that even abstract properties derive ultimately from these physical atoms. Unless we want to postulate logical atoms, or monads, or some such weird thing.
8. Modes of Existence / B. Properties / 5. Natural Properties
'Being physical' is a second-order property [Molnar]
     Full Idea: A property like 'being physical' is just a second-order property. ...It is not required as a first-order property. ...Higher-order properties earn their keep as necessity-makers.
     From: George Molnar (Powers [1998], 1.4.2)
     A reaction: I take this to be correct and very important. People who like 'abundant' properties don't make this distinction about orders (of levels of abstraction, I would say), so the whole hierarchy has an equal status in ontology, which is ridiculous.
8. Modes of Existence / B. Properties / 6. Categorical Properties
'Categorical properties' are those which are not powers [Molnar]
     Full Idea: The canonical name for a property that is a non-power is 'categorical property'.
     From: George Molnar (Powers [1998], 10.2)
     A reaction: Molnar objects that this implies that powers cannot be used categorically, and refuses to use the term. There seems to be uncertainty over whether the term refers to necessity, or to the ability to categorise. I'm getting confused myself.
8. Modes of Existence / B. Properties / 13. Tropes / a. Nature of tropes
Are tropes transferable? If they are, that is a version of Platonism [Molnar]
     Full Idea: Are tropes transferable? ...If tropes are not dependent on their bearers, that is a trope-theoretic version of Platonism.
     From: George Molnar (Powers [1998], 1.4.6)
     A reaction: These are the sort of beautifully simple questions that we pay philosophers to come up with. If they are transferable, what was the loose bond which connected them? If they aren't, then what individuates them?
8. Modes of Existence / C. Powers and Dispositions / 1. Powers
A power's type-identity is given by its definitive manifestation [Molnar]
     Full Idea: A power's type-identity is given by its definitive manifestation.
     From: George Molnar (Powers [1998], 3.1)
     A reaction: Presumably there remains an I-know-not-what that lurks behind the manifestation, which is beyond our limits of cognizance. The ultimate reality of the world has to be unknowable.
Powers have Directedness, Independence, Actuality, Intrinsicality and Objectivity [Molnar]
     Full Idea: The basic features of powers are: Directedness (to some outcome); Independence (from their manifestations); Actuality (not mere possibilities); Intrinsicality (not relying on other objects) and Objectivity (rather than psychological).
     From: George Molnar (Powers [1998], 2.4)
     A reaction: [compression of his list] This offering is why Molnar's book is important, because no one else seems to get to grips with trying to pin down what a power is, and hence their role.
8. Modes of Existence / C. Powers and Dispositions / 2. Powers as Basic
The physical world has a feature very like mental intentionality [Molnar]
     Full Idea: Something very much like mental intentionality is a pervasive and ineliminable feature of the physical world.
     From: George Molnar (Powers [1998], 3.2)
     A reaction: I like this, because it offers a continuous account of mind and world. The idea that intentionality is some magic ingredient that marks off a non-physical type of reality is nonsense. See Fodor's attempts to reduce intentionality.
Dispositions and external powers arise entirely from intrinsic powers in objects [Molnar]
     Full Idea: I propose a generalization: that all dispositional and extrinsic predicates that apply to an object, do so by virtue of intrinsic powers borne by the object.
     From: George Molnar (Powers [1998], 6.3)
     A reaction: This is the clearest statement of the 'powers' view of nature, and the one with which I agree. An interesting question is whether powers or objects are more basic in our ontology. Are objects just collections of causal powers? What has the power?
The Standard Model suggest that particles are entirely dispositional, and hence are powers [Molnar]
     Full Idea: In the Standard Model of physics the fundamental physical magnitudes are represented as ones whose whole nature is exhausted by the dispositionality, ..so there is a strong presumption that the properties of subatomic particles are powers.
     From: George Molnar (Powers [1998], 8.4.3)
     A reaction: A very nice point, because it asserts not merely that we should revise our metaphysic to endorse powers, but that we are actually already operating with exactly that view, in so far as we are physicalist.
Some powers are ungrounded, and others rest on them, and are derivative [Molnar]
     Full Idea: Some powers are grounded and some are not. ...All derivative powers ultimately derive from ungrounded powers.
     From: George Molnar (Powers [1998], 8.5.2)
     A reaction: It is tempting to use the term 'property' for the derivative powers, reserving 'power' for something which is basic. Molnar makes a plausible case, though.
8. Modes of Existence / C. Powers and Dispositions / 6. Dispositions / a. Dispositions
Dispositions can be causes, so they must be part of the actual world [Molnar]
     Full Idea: Dispositions can be causes. What is not actual cannot be a cause or any part of a cause. Merely possible events are not actual, and that makes them causally impotent. The claim that powers are causally potent has strong initial plausibility.
     From: George Molnar (Powers [1998], 5)
     A reaction: [He credits Mellor 1974 for this idea] He will need to show how dispositions can be causes (other than, presumably, being anticipated or imagined by conscious minds), which he says he will do in Ch. 12.
8. Modes of Existence / C. Powers and Dispositions / 6. Dispositions / b. Dispositions and powers
If powers only exist when actual, they seem to be nomadic, and indistinguishable from non-powers [Molnar]
     Full Idea: Two arguments against Megaran Actualism are that it turns powers into nomads: they come and go, depending on whether they are being exercised or not. And it stops us from distinguishing between unexercised powers and absent powers.
     From: George Molnar (Powers [1998], 4.3.1)
     A reaction: See Idea 11938 for Megaran Actualism. Molnar takes these objections to be fairly decisive, but if the Megarans are denying the existence of latent powers, they aren't going to be bothered by nomadism or the lack of distinction.
8. Modes of Existence / D. Universals / 6. Platonic Forms / d. Forms critiques
Platonic explanations of universals actually diminish our understanding [Molnar]
     Full Idea: We understand less after a platonic explanation of universals than we understand before it was given.
     From: George Molnar (Powers [1998], 1.2)
     A reaction: That pretty much sums up my view, and it pretty well sums up my view of religion as well. I thought I understood what numbers were until Frege told me that they were abstract objects, some sort of higher-order set.
8. Modes of Existence / E. Nominalism / 1. Nominalism / a. Nominalism
For nominalists, predicate extensions are inexplicable facts [Molnar]
     Full Idea: For the nominalist, belonging to the extension of a predicate is just an inexplicable ultimate fact.
     From: George Molnar (Powers [1998], 1.2)
     A reaction: I sometimes think of myself as a nominalist, but when it is summarised in Molnar's way I back off. He seem to be offering a third way, between platonic realism and nominalism. It is physical essentialist realism, I think.
Nominalists only accept first-order logic [Molnar]
     Full Idea: A nominalist will only countenance first-order logic.
     From: George Molnar (Powers [1998], 12.2.2)
     A reaction: This is because nominalist will not acknowledge properties as entities to be quantified over. Plural quantification seems to be a strategy for extending first-order logic while retaining nominalist sympathies.
9. Objects / C. Structure of Objects / 1. Structure of an Object
Structural properties are derivate properties [Molnar]
     Full Idea: Structural properties are clear examples of derivative properties.
     From: George Molnar (Powers [1998], 1.4.3)
     A reaction: This is an important question in the debate. Presumably you can't just reduce structural properties to more basic ones, because one set of basic properties might appear in many different structures. Ellis defends structural properties in metaphysics.
There are no 'structural properties', as properties with parts [Molnar]
     Full Idea: There are no 'structural properties', if by that we mean a property that has properties as parts.
     From: George Molnar (Powers [1998], 9.1.2)
     A reaction: There do seem to be properties that result from arranging more basic properties in one way rather than another (e.g. arranging the metal in a knife to be 'sharp'). But I think Molnar is right that they are not part of basic ontology.
9. Objects / D. Essence of Objects / 7. Essence and Necessity / b. Essence not necessities
The essence of a thing need not include everything that is necessarily true of it [Molnar]
     Full Idea: Pre-theoretically it does not seem to be the case that what is essential to a thing includes everything that is necessarily true of that thing.
     From: George Molnar (Powers [1998], 1.4.4)
     A reaction: This seems to me to be true. The simple point, which I take to be obvious, is that essential properties must at the very least be in some way important, whereas necessities can be trivial. I favour the idea that the essences create the necessities.
10. Modality / B. Possibility / 1. Possibility
What is the truthmaker for a non-existent possible? [Molnar]
     Full Idea: What is the nature of the truthmaker for 'It is possible that p' in cases where p itself is false?
     From: George Molnar (Powers [1998], 12.2.2)
     A reaction: Molnar mentions three views: there is a different type of being for possibilia (Meinong), or possibilia exist, or possibilia are merely represented. The third view is obviously correct, though I presume possibilia to be based on actual powers.
11. Knowledge Aims / A. Knowledge / 4. Belief / c. Aim of beliefs
Some claim that indicative conditionals are believed by people, even though they are not actually held true [Horsten]
     Full Idea: In the debate about doxastic attitudes towards indicative conditional sentences, one finds philosophers who claim that conditionals can be believed even though they have no truth value (and thus are not true).
     From: Leon Horsten (The Tarskian Turn [2011], 09.3)
14. Science / D. Explanation / 1. Explanation / a. Explanation
Hume allows interpolation, even though it and extrapolation are not actually valid [Molnar]
     Full Idea: In his 'shade of blue' example, Hume is (sensibly) endorsing a type of reasoning - interpolation - that is widely used by rational thinkers. Too bad that interpolation and extrapolation are incurably invalid.
     From: George Molnar (Powers [1998], 7.2.3)
     A reaction: Interpolation and extrapolation are two aspects of inductive reasoning which contribute to our notion of best explanation. Empiricism has to allow at least some knowledge which goes beyond strict direct experience.
15. Nature of Minds / A. Nature of Mind / 1. Mind / a. Mind
The two ways proposed to distinguish mind are intentionality or consciousness [Molnar]
     Full Idea: There have only been two serious proposals for distinguishing mind from matter. One appeals to intentionality, as per Brentano and his medieval precursors. The other, harking back to Descartes, Locke and empiricism, uses the capacity for consciousness.
     From: George Molnar (Powers [1998], 3.5.3)
     A reaction: Personally I take both of these to be reducible, and hence have no place for 'minds' in my ontology. Focusing on Chalmers's 'Hard Question' was the shift from the intentionality view to the consciousness view which is now more popular.
15. Nature of Minds / B. Features of Minds / 4. Intentionality / a. Nature of intentionality
Physical powers like solubility and charge also have directedness [Molnar]
     Full Idea: Contrary to the Brentano Thesis, physical powers, such as solubility or electromagnetic charge, also have that direction toward something outside themselves that is typical of psychological attributes.
     From: George Molnar (Powers [1998], 3.4)
     A reaction: I think this decisively undermines any strong thesis that 'intentionality is the mark of the mental'. I take thought to be just a fancy development of the physical powers of the physical world.
17. Mind and Body / A. Mind-Body Dualism / 4. Occasionalism
Rule occasionalism says God's actions follow laws, not miracles [Molnar]
     Full Idea: Rule occasionalists (Arnauld, Bayle) say that on their view the results of God's action are the nomic regularities of nature, and not a miracle.
     From: George Molnar (Powers [1998], 6.1)
     A reaction: This is clearly more plausible that Malebranche's idea that God constantly intervenes. I take it as a nice illustration of the fact that 'laws of nature' were mainly invented by us to explain how God could control his world. Away with them!
19. Language / C. Assigning Meanings / 1. Syntax
A theory of syntax can be based on Peano arithmetic, thanks to the translation by Gödel coding [Horsten]
     Full Idea: A notion of formal provability can be articulated in Peano arithmetic. ..This is surprisingly 'linguistic' rather than mathematical, but the key is in the Gödel coding. ..Hence we use Peano arithmetic as a theory of syntax.
     From: Leon Horsten (The Tarskian Turn [2011], 02.4)
     A reaction: This is the explanation of why issues in formal semantics end up being studied in systems based on formal arithmetic. And I had thought it was just because they were geeks who dream in numbers, and can't speak language properly...
26. Natural Theory / C. Causation / 2. Types of cause
Singular causation is prior to general causation; each aspirin produces the aspirin generalization [Molnar]
     Full Idea: I take for granted the primacy of singular causation. A singular causal state of affairs is not constituted by a generalization. 'Aspirin relieves headache' is made true by 'This/that aspirin relieves this/that headache'.
     From: George Molnar (Powers [1998], 12.1)
     A reaction: [He cites Tooley for the opposite view] I wholly agree with Molnar, and am inclined to link it with the primacy of individual essences over kind essences.
26. Natural Theory / C. Causation / 4. Naturalised causation
We should analyse causation in terms of powers, not vice versa [Molnar]
     Full Idea: Causal analyses of powers pre-empt the correct account of causation in terms of powers.
     From: George Molnar (Powers [1998], 4.2.3)
     A reaction: I think this is my preferred view. The crucial point is that powers are active, so one is not needing to add some weird 'causation' ingredient to a world which would otherwise be passive and inert. That is a relic from the interventions of God.
26. Natural Theory / C. Causation / 7. Eliminating causation
We should analyse causation in terms of powers [Molnar]
     Full Idea: We should give up any causal analysis of powers, ..so we should try to analyse causation in terms of powers.
     From: George Molnar (Powers [1998], 8.5.3)
     A reaction: It may be hard to explain what powers are, or identify them, if you can't say that they cause things to happen. I am torn between Molnar's view, and the view that causation is primitive.
26. Natural Theory / C. Causation / 9. General Causation / c. Counterfactual causation
Causal dependence explains counterfactual dependence, not vice versa [Molnar]
     Full Idea: The counterfactual analysis is open to the Euthyphro objection: it is causal dependence that explains any counterfactual dependence rather than vice versa.
     From: George Molnar (Powers [1998], 12.1)
     A reaction: I take views like the counterfactual analysis of causation to arise from empiricists who are bizarrely reluctant to adopt plausible best explainations (such as powers and essences).
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / a. Scientific essentialism
Science works when we assume natural kinds have essences - because it is true [Molnar]
     Full Idea: Investigations premissed on the assumption that natural kinds have essences, that in particular the fundamental natural kinds have only essential intrinsic properties, tend to be practically successful because the assumption is true.
     From: George Molnar (Powers [1998], 11.3)
     A reaction: The point is made against a pragmatist approach to the problem by Nancy Cartwright. I take the starting point for scientific essentialism to be an empirical observation, that natural kinds seem to be very very stable. See Idea 8153.
Location in space and time are non-power properties [Molnar, by Mumford]
     Full Idea: Molnar argues that some properties are non-powers, and he cites spatial location, spatial orientation, and temporal location.
     From: report of George Molnar (Powers [1998], 158-62) by Stephen Mumford - Laws in Nature 11.4
     A reaction: Although you might say an event happened 'because' of an item on this list, this doesn't feel right to me. The ability to arrest someone is a power, but being at the scene of the crime isn't. It's an opportunity for a power.
One essential property of a muon doesn't entail the others [Molnar]
     Full Idea: The muon has mass 106.2 MeV, unit negative charge, and spin a half. The electron and tauon have unit negative charge, but electrons are 200 times less massive, and tauons 17 times more massive. Its essential properties are not mutually entailing.
     From: George Molnar (Powers [1998], 2.1)
     A reaction: This rejects a popular idea of scientific essentialism, that the essence is the set of properties which entail the non-essential properties (and not vice versa), a view which I had hitherto found rather appealing.
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / b. Scientific necessity
It is contingent which kinds and powers exist in the world [Molnar]
     Full Idea: It is a contingent matter that the world contains the exact natural kinds it does, and hence it is a contingent matter that it contains the very powers it does.
     From: George Molnar (Powers [1998], 10.3)
     A reaction: I take this to be correct (for all we know). It would be daft to claim that the regularities of the universe are necessarily that way, but it is not daft to say that the stuff of the universe necessitates the pattern of what happens.
26. Natural Theory / D. Laws of Nature / 11. Against Laws of Nature
The laws of nature depend on the powers, not the other way round [Molnar]
     Full Idea: What powers there are does not depend on what laws there are, but vice versa, what laws obtain in the world is a function of what powers are to be found in that world.
     From: George Molnar (Powers [1998], 1.4.5)
     A reaction: This old idea may well be the most important realisation of modern times. I take the 'law' view to be based on a religious view of the world (see Idea 5470). There is still room to believe in a divine creator of the bewildering underlying powers.
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / b. Fields
Energy fields are discontinuous at the very small [Molnar]
     Full Idea: We know that all energy fields are discontinuous below the distance measured by Planck's constant h. The physical world ultimately consists of discrete objects.
     From: George Molnar (Powers [1998], 2.2)
     A reaction: This is where quantum theory clashes with relativity, since the latter holds space to be a continuum. I'm not sure about Molnar's use of the word 'objects' here.