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68 ideas

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the spirit of metaphysics since Saul Kripke's work, though some people engaged in it seem to me to be trapped in an outdated linguistic view of the matter.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 / 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.
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / b. Terminology of ST
'Forcing' can produce new models of ZFC from old models [Maddy]
     Full Idea: Cohen's method of 'forcing' produces a new model of ZFC from an old model by appending a carefully chosen 'generic' set.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.4)
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
A Large Cardinal Axiom would assert ever-increasing stages in the hierarchy [Maddy]
     Full Idea: A possible axiom is the Large Cardinal Axiom, which asserts that there are more and more stages in the cumulative hierarchy. Infinity can be seen as the first of these stages, and Replacement pushes further in this direction.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.5)
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / f. Axiom of Infinity V
Axiom of Infinity: completed infinite collections can be treated mathematically [Maddy]
     Full Idea: The axiom of infinity: that there are infinite sets is to claim that completed infinite collections can be treated mathematically. In its standard contemporary form, the axioms assert the existence of the set of all finite ordinals.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.3)
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / i. Axiom of Foundation VIII
The Axiom of Foundation says every set exists at a level in the set hierarchy [Maddy]
     Full Idea: In the presence of other axioms, the Axiom of Foundation is equivalent to the claim that every set is a member of some Vα.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.3)
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / p. Axiom of Reducibility
Axiom of Reducibility: propositional functions are extensionally predicative [Maddy]
     Full Idea: The Axiom of Reducibility states that every propositional function is extensionally equivalent to some predicative proposition function.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.1)
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
If a sound conclusion comes from two errors that cancel out, the path of the argument must matter [Rumfitt]
     Full Idea: If a designated conclusion follows from the premisses, but the argument involves two howlers which cancel each other out, then the moral is that the path an argument takes from premisses to conclusion does matter to its logical evaluation.
     From: Ian Rumfitt ("Yes" and "No" [2000], II)
     A reaction: The drift of this is that our view of logic should be a little closer to the reasoning of ordinary language, and we should rely a little less on purely formal accounts.
5. Theory of Logic / E. Structures of Logic / 1. Logical Form
'Propositional functions' are propositions with a variable as subject or predicate [Maddy]
     Full Idea: A 'propositional function' is generated when one of the terms of the proposition is replaced by a variable, as in 'x is wise' or 'Socrates'.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.1)
     A reaction: This implies that you can only have a propositional function if it is derived from a complete proposition. Note that the variable can be in either subject or in predicate position. It extends Frege's account of a concept as 'x is F'.
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
The sense of a connective comes from primitively obvious rules of inference [Rumfitt]
     Full Idea: A connective will possess the sense that it has by virtue of its competent users' finding certain rules of inference involving it to be primitively obvious.
     From: Ian Rumfitt ("Yes" and "No" [2000], III)
     A reaction: Rumfitt cites Peacocke as endorsing this view, which characterises the logical connectives by their rules of usage rather than by their pure semantic value.
Standardly 'and' and 'but' are held to have the same sense by having the same truth table [Rumfitt]
     Full Idea: If 'and' and 'but' really are alike in sense, in what might that likeness consist? Some philosophers of classical logic will reply that they share a sense by virtue of sharing a truth table.
     From: Ian Rumfitt ("Yes" and "No" [2000])
     A reaction: This is the standard view which Rumfitt sets out to challenge.
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / d. Actual infinite
Completed infinities resulted from giving foundations to calculus [Maddy]
     Full Idea: The line of development that finally led to a coherent foundation for the calculus also led to the explicit introduction of completed infinities: each real number is identified with an infinite collection of rationals.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.3)
     A reaction: Effectively, completed infinities just are the real numbers.
Cantor and Dedekind brought completed infinities into mathematics [Maddy]
     Full Idea: Both Cantor's real number (Cauchy sequences of rationals) and Dedekind's cuts involved regarding infinite items (sequences or sets) as completed and subject to further manipulation, bringing the completed infinite into mathematics unambiguously.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.1 n39)
     A reaction: So it is the arrival of the real numbers which is the culprit for lumbering us with weird completed infinites, which can then be the subject of addition, multiplication and exponentiation. Maybe this was a silly mistake?
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / i. Cardinal infinity
Infinity has degrees, and large cardinals are the heart of set theory [Maddy]
     Full Idea: The stunning discovery that infinity comes in different degrees led to the theory of infinite cardinal numbers, the heart of contemporary set theory.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.1)
     A reaction: It occurs to me that these huge cardinals only exist in set theory. If you took away that prop, they would vanish in a puff.
For any cardinal there is always a larger one (so there is no set of all sets) [Maddy]
     Full Idea: By the mid 1890s Cantor was aware that there could be no set of all sets, as its cardinal number would have to be the largest cardinal number, while his own theorem shows that for any cardinal there is a larger.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.1)
     A reaction: There is always a larger cardinal because of the power set axiom. Some people regard that with suspicion.
An 'inaccessible' cardinal cannot be reached by union sets or power sets [Maddy]
     Full Idea: An 'inaccessible' cardinal is one that cannot be reached by taking unions of small collections of smaller sets or by taking power sets.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.5)
     A reaction: They were introduced by Hausdorff in 1908.
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / l. Limits
Theorems about limits could only be proved once the real numbers were understood [Maddy]
     Full Idea: Even the fundamental theorems about limits could not [at first] be proved because the reals themselves were not well understood.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.2)
     A reaction: This refers to the period of about 1850 (Weierstrass) to 1880 (Dedekind and Cantor).
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / c. Fregean numbers
The extension of concepts is not important to me [Maddy]
     Full Idea: I attach no decisive importance even to bringing in the extension of the concepts at all.
     From: Penelope Maddy (Naturalism in Mathematics [1997], §107)
     A reaction: He almost seems to equate the concept with its extension, but that seems to raise all sorts of questions, about indeterminate and fluctuating extensions.
In the ZFC hierarchy it is impossible to form Frege's set of all three-element sets [Maddy]
     Full Idea: In the ZFC cumulative hierarchy, Frege's candidates for numbers do not exist. For example, new three-element sets are formed at every stage, so there is no stage at which the set of all three-element sets could he formed.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.2)
     A reaction: Ah. This is a very important fact indeed if you are trying to understand contemporary discussions in philosophy of mathematics.
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / e. Caesar problem
Frege solves the Caesar problem by explicitly defining each number [Maddy]
     Full Idea: To solve the Julius Caesar problem, Frege requires explicit definitions of the numbers, and he proposes his well-known solution: the number of Fs = the extension of the concept 'equinumerous with F' (based on one-one correspondence).
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.1)
     A reaction: Why do there have to be Fs before there can be the corresponding number? If there were no F for 523, would that mean that '523' didn't exist (even if 522 and 524 did exist)?
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Making set theory foundational to mathematics leads to very fruitful axioms [Maddy]
     Full Idea: The set theory axioms developed in producing foundations for mathematics also have strong consequences for existing fields, and produce a theory that is immensely fruitful in its own right.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.2)
     A reaction: [compressed] Second of Maddy's three benefits of set theory. This benefit is more questionable than the first, because the axioms may be invented because of their nice fruit, instead of their accurate account of foundations.
Unified set theory gives a final court of appeal for mathematics [Maddy]
     Full Idea: The single unified area of set theory provides a court of final appeal for questions of mathematical existence and proof.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.2)
     A reaction: Maddy's third benefit of set theory. 'Existence' means being modellable in sets, and 'proof' means being derivable from the axioms. The slightly ad hoc character of the axioms makes this a weaker defence.
Set theory brings mathematics into one arena, where interrelations become clearer [Maddy]
     Full Idea: Set theoretic foundations bring all mathematical objects and structures into one arena, allowing relations and interactions between them to be clearly displayed and investigated.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.2)
     A reaction: The first of three benefits of set theory which Maddy lists. The advantages of the one arena seem to be indisputable.
Identifying geometric points with real numbers revealed the power of set theory [Maddy]
     Full Idea: The identification of geometric points with real numbers was among the first and most dramatic examples of the power of set theoretic foundations.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.2)
     A reaction: Hence the clear definition of the reals by Dedekind and Cantor was the real trigger for launching set theory.
The line of rationals has gaps, but set theory provided an ordered continuum [Maddy]
     Full Idea: The structure of a geometric line by rational points left gaps, which were inconsistent with a continuous line. Set theory provided an ordering that contained no gaps. These reals are constructed from rationals, which come from integers and naturals.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.2)
     A reaction: This completes the reduction of geometry to arithmetic and algebra, which was launch 250 years earlier by Descartes.
Mathematics rests on the logic of proofs, and on the set theoretic axioms [Maddy]
     Full Idea: Our much loved mathematical knowledge rests on two supports: inexorable deductive logic (the stuff of proof), and the set theoretic axioms.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I Intro)
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / b. Indispensability of mathematics
Maybe applications of continuum mathematics are all idealisations [Maddy]
     Full Idea: It could turn out that all applications of continuum mathematics in natural sciences are actually instances of idealisation.
     From: Penelope Maddy (Naturalism in Mathematics [1997], II.6)
Scientists posit as few entities as possible, but set theorist posit as many as possible [Maddy]
     Full Idea: Crudely, the scientist posits only those entities without which she cannot account for observations, while the set theorist posits as many entities as she can, short of inconsistency.
     From: Penelope Maddy (Naturalism in Mathematics [1997], II.5)
6. Mathematics / C. Sources of Mathematics / 6. Logicism / c. Neo-logicism
We can get arithmetic directly from HP; Law V was used to get HP from the definition of number [Maddy]
     Full Idea: Recent commentators have noted that Frege's versions of the basic propositions of arithmetic can be derived from Hume's Principle alone, that the fatal Law V is only needed to derive Hume's Principle itself from the definition of number.
     From: Penelope Maddy (Naturalism in Mathematics [1997], I.1)
     A reaction: Crispin Wright is the famous exponent of this modern view. Apparently Charles Parsons (1965) first floated the idea.
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 / 11. Ontological Commitment / e. Ontological commitment problems
The theoretical indispensability of atoms did not at first convince scientists that they were real [Maddy]
     Full Idea: The case of atoms makes it clear that the indispensable appearance of an entity in our best scientific theory is not generally enough to convince scientists that it is real.
     From: Penelope Maddy (Naturalism in Mathematics [1997], II.6)
     A reaction: She refers to the period between Dalton and Einstein, when theories were full of atoms, but there was strong reluctance to actually say that they existed, until the direct evidence was incontrovertable. Nice point.
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.
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.
15. Nature of Minds / C. Capacities of Minds / 6. Idealisation
Science idealises the earth's surface, the oceans, continuities, and liquids [Maddy]
     Full Idea: In science we treat the earth's surface as flat, we assume the ocean to be infinitely deep, we use continuous functions for what we know to be quantised, and we take liquids to be continuous despite atomic theory.
     From: Penelope Maddy (Naturalism in Mathematics [1997], II.6)
     A reaction: If fussy people like scientists do this all the time, how much more so must the confused multitude be doing the same thing all day?
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 / F. Communication / 3. Denial
We learn 'not' along with affirmation, by learning to either affirm or deny a sentence [Rumfitt]
     Full Idea: The standard view is that affirming not-A is more complex than affirming the atomic sentence A itself, with the latter determining its sense. But we could learn 'not' directly, by learning at once how to either affirm A or reject A.
     From: Ian Rumfitt ("Yes" and "No" [2000], IV)
     A reaction: [compressed] This seems fairly anti-Fregean in spirit, because it looks at the psychology of how we learn 'not' as a way of clarifying what we mean by it, rather than just looking at its logical behaviour (and thus giving it a secondary role).
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.