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All the ideas for 'The Evolution of Logic', 'Human Personality' and 'How Things Persist'

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102 ideas

1. Philosophy / C. History of Philosophy / 4. Later European Philosophy / c. Eighteenth century philosophy
We are all post-Kantians, because he set the current agenda for philosophy [Hart,WD]
     Full Idea: We are all post-Kantians, ...because Kant set an agenda for philosophy that we are still working through.
     From: William D. Hart (The Evolution of Logic [2010], 2)
     A reaction: Hart says that the main agenda is set by Kant's desire to defend the principle of sufficient reason against Hume's attack on causation. I would take it more generally to be the assessment of metaphysics, and of a priori knowledge.
1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / d. Philosophy as puzzles
The problems are the monuments of philosophy [Hart,WD]
     Full Idea: The real monuments of philosophy are its problems.
     From: William D. Hart (The Evolution of Logic [2010], 2)
     A reaction: Presumably he means '....rather than its solutions'. No other subject would be very happy with that sort of claim. Compare Idea 8243. A complaint against analytic philosophy is that it has achieved no consensus at all.
1. Philosophy / D. Nature of Philosophy / 7. Despair over Philosophy
Philosophers are good at denying the obvious [Hawley]
     Full Idea: Philosophers are skilled at resisting even the most inviting thoughts.
     From: Katherine Hawley (How Things Persist [2001], 5)
     A reaction: Not exactly 'despair', but it does show how far philosophers are able to stray from common sense. Monads, real possible worlds, real sets… Thomas Reid, the philosopher of common sense, might be the antidote.
1. Philosophy / F. Analytic Philosophy / 6. Logical Analysis
To study abstract problems, some knowledge of set theory is essential [Hart,WD]
     Full Idea: By now, no education in abstract pursuits is adequate without some familiarity with sets.
     From: William D. Hart (The Evolution of Logic [2010], 10)
     A reaction: A heart-sinking observation for those who aspire to study metaphysics and modality. The question is, what will count as 'some' familiarity? Are only professional logicians now allowed to be proper philosophers?
3. Truth / A. Truth Problems / 3. Value of Truth
Genius and love of truth are always accompanied by great humility [Weil]
     Full Idea: Love of truth is always accompanied by humility, and real genius is nothing else but the supernatural virtue of humility in the domain of thought.
     From: Simone Weil (Human Personality [1943], p.87)
     A reaction: A striking and attractive thought, true of all the lovers of truth I have ever encountered. Socrates is the role model. She likens truth to an inarticulate plaintiff stammering before a judge who fluently manipulates opinions.
3. Truth / C. Correspondence Truth / 2. Correspondence to Facts
Tarski showed how we could have a correspondence theory of truth, without using 'facts' [Hart,WD]
     Full Idea: It is an ancient and honourable view that truth is correspondence to fact; Tarski showed us how to do without facts here.
     From: William D. Hart (The Evolution of Logic [2010], 2)
     A reaction: This is a very interesting spin on Tarski, who certainly seems to endorse the correspondence theory, even while apparently inventing a new 'semantic' theory of truth. It is controversial how far Tarski's theory really is a 'correspondence' theory.
3. Truth / F. Semantic Truth / 1. Tarski's Truth / b. Satisfaction and truth
Truth for sentences is satisfaction of formulae; for sentences, either all sequences satisfy it (true) or none do [Hart,WD]
     Full Idea: We explain truth for sentences in terms of satisfaction of formulae. The crux here is that for a sentence, either all sequences satisfy it or none do (with no middle ground). For formulae, some sequences may satisfy it and others not.
     From: William D. Hart (The Evolution of Logic [2010], 4)
     A reaction: This is the hardest part of Tarski's theory of truth to grasp.
3. Truth / F. Semantic Truth / 2. Semantic Truth
A first-order language has an infinity of T-sentences, which cannot add up to a definition of truth [Hart,WD]
     Full Idea: In any first-order language, there are infinitely many T-sentences. Since definitions should be finite, the agglomeration of all the T-sentences is not a definition of truth.
     From: William D. Hart (The Evolution of Logic [2010], 4)
     A reaction: This may be a warning shot aimed at Davidson's extensive use of Tarski's formal account in his own views on meaning in natural language.
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / c. Derivation rules of PL
Conditional Proof: infer a conditional, if the consequent can be deduced from the antecedent [Hart,WD]
     Full Idea: A 'conditional proof' licenses inferences to a conditional from a deduction of its consequent from its antecedent.
     From: William D. Hart (The Evolution of Logic [2010], 4)
     A reaction: That is, a proof can be enshrined in an arrow.
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / e. Existential quantifier ∃
∃y... is read as 'There exists an individual, call it y, such that...', and not 'There exists a y such that...' [Hart,WD]
     Full Idea: When a quantifier is attached to a variable, as in '∃(y)....', then it should be read as 'There exists an individual, call it y, such that....'. One should not read it as 'There exists a y such that...', which would attach predicate to quantifier.
     From: William D. Hart (The Evolution of Logic [2010], 4)
     A reaction: The point is to make clear that in classical logic the predicates attach to the objects, and not to some formal component like a quantifier.
4. Formal Logic / F. Set Theory ST / 1. Set Theory
Set theory articulates the concept of order (through relations) [Hart,WD]
     Full Idea: It is set theory, and more specifically the theory of relations, that articulates order.
     From: William D. Hart (The Evolution of Logic [2010])
     A reaction: It would seem that we mainly need set theory in order to talk accurately about order, and about infinity. The two come together in the study of the ordinal numbers.
Nowadays ZFC and NBG are the set theories; types are dead, and NF is only useful for the whole universe [Hart,WD]
     Full Idea: The theory of types is a thing of the past. There is now nothing to choose between ZFC and NBG (Neumann-Bernays-Gödel). NF (Quine's) is a more specialized taste, but is a place to look if you want the universe.
     From: William D. Hart (The Evolution of Logic [2010], 3)
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / a. Symbols of ST
∈ relates across layers, while ⊆ relates within layers [Hart,WD]
     Full Idea: ∈ relates across layers (Plato is a member of his unit set and the set of people), while ⊆ relates within layers (the singleton of Plato is a subset of the set of people). This distinction only became clear in the 19th century.
     From: William D. Hart (The Evolution of Logic [2010], 1)
     A reaction: Getting these two clear may be the most important distinction needed to understand how set theory works.
4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
Without the empty set we could not form a∩b without checking that a and b meet [Hart,WD]
     Full Idea: Without the empty set, disjoint sets would have no intersection, and we could not form a∩b without checking that a and b meet. This is an example of the utility of the empty set.
     From: William D. Hart (The Evolution of Logic [2010], 1)
     A reaction: A novice might plausibly ask why there should be an intersection for every pair of sets, if they have nothing in common except for containing this little puff of nothingness. But then what do novices know?
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / i. Axiom of Foundation VIII
In the modern view, foundation is the heart of the way to do set theory [Hart,WD]
     Full Idea: In the second half of the twentieth century there emerged the opinion that foundation is the heart of the way to do set theory.
     From: William D. Hart (The Evolution of Logic [2010], 3)
     A reaction: It is foundation which is the central axiom of the iterative conception of sets, where each level of sets is built on previous levels, and they are all 'well-founded'.
Foundation Axiom: an nonempty set has a member disjoint from it [Hart,WD]
     Full Idea: The usual statement of Foundation is that any nonempty set has a member disjoint from it. This phrasing is ordinal-free and closer to the primitives of ZFC.
     From: William D. Hart (The Evolution of Logic [2010], 3)
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
We can choose from finite and evident sets, but not from infinite opaque ones [Hart,WD]
     Full Idea: When a set is finite, we can prove it has a choice function (∀x x∈A → f(x)∈A), but we need an axiom when A is infinite and the members opaque. From infinite shoes we can pick a left one, but from socks we need the axiom of choice.
     From: William D. Hart (The Evolution of Logic [2010], 1)
     A reaction: The socks example in from Russell 1919:126.
With the Axiom of Choice every set can be well-ordered [Hart,WD]
     Full Idea: It follows from the Axiom of Choice that every set can be well-ordered.
     From: William D. Hart (The Evolution of Logic [2010], 1)
     A reaction: For 'well-ordered' see Idea 13460. Every set can be ordered with a least member.
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / o. Axiom of Constructibility V = L
If we accept that V=L, it seems to settle all the open questions of set theory [Hart,WD]
     Full Idea: It has been said (by Burt Dreben) that the only reason set theorists do not generally buy the view that V = L is that it would put them out of business by settling their open questions.
     From: William D. Hart (The Evolution of Logic [2010], 10)
     A reaction: Hart says V=L breaks with the interative conception of sets at level ω+1, which is countable is the constructible view, but has continuum many in the cumulative (iterative) hierarch. The constructible V=L view is anti-platonist.
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / d. Naïve logical sets
Naïve set theory has trouble with comprehension, the claim that every predicate has an extension [Hart,WD]
     Full Idea: 'Comprehension' is the assumption that every predicate has an extension. Naïve set theory is the theory whose axioms are extensionality and comprehension, and comprehension is thought to be its naivety.
     From: William D. Hart (The Evolution of Logic [2010], 1)
     A reaction: This doesn't, of course, mean that there couldn't be a more modest version of comprehension. The notorious difficulty come with the discovery of self-referring predicates which can't possibly have extensions.
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / e. Iterative sets
The iterative conception may not be necessary, and may have fixed points or infinitely descending chains [Hart,WD]
     Full Idea: That the iterative sets suffice for most of ZFC does not show they are necessary, nor is it evident that the set of operations has no fixed points (as 0 is a fixed point for square-of), and no infinitely descending chains (like negative integers).
     From: William D. Hart (The Evolution of Logic [2010], 3)
     A reaction: People don't seem to worry that they aren't 'necessary', and further measures are possible to block infinitely descending chains.
4. Formal Logic / F. Set Theory ST / 6. Ordering in Sets
A 'partial ordering' is irreflexive and transitive; the sets are ordered, but not the subsets [Hart,WD]
     Full Idea: We say that a binary relation R 'partially orders' a field A just in case R is irreflexive (so that nothing bears R to itself) and transitive. When the set is {a,b}, its subsets {a} and {b} are incomparable in a partial ordering.
     From: William D. Hart (The Evolution of Logic [2010], 1)
A partial ordering becomes 'total' if any two members of its field are comparable [Hart,WD]
     Full Idea: A partial ordering is a 'total ordering' just in case any two members of its field are comparable, that is, either a is R to b, or b is R to a, or a is b.
     From: William D. Hart (The Evolution of Logic [2010], 1)
     A reaction: See Idea 13457 for 'partial ordering'. The three conditions are known as the 'trichotomy' condition.
'Well-ordering' must have a least member, so it does the natural numbers but not the integers [Hart,WD]
     Full Idea: A total order 'well-orders' its field just in case any nonempty subset B of its field has an R-least member, that is, there is a b in B such that for any a in B different from b, b bears R to a. So less-than well-orders natural numbers, but not integers.
     From: William D. Hart (The Evolution of Logic [2010], 1)
     A reaction: The natural numbers have a starting point, but the integers are infinite in both directions. In plain English, an order is 'well-ordered' if there is a starting point.
Von Neumann defines α<β as α∈β [Hart,WD]
     Full Idea: One of the glories of Von Neumann's theory of numbers is to define α < β to mean that α ∈ β.
     From: William D. Hart (The Evolution of Logic [2010], 3)
4. Formal Logic / F. Set Theory ST / 8. Critique of Set Theory
Maybe sets should be rethought in terms of the even more basic categories [Hart,WD]
     Full Idea: Some have claimed that sets should be rethought in terms of still more basic things, categories.
     From: William D. Hart (The Evolution of Logic [2010], 2)
     A reaction: [He cites F.William Lawvere 1966] It appears to the the context of foundations for mathematics that he has in mind.
5. Theory of Logic / F. Referring in Logic / 1. Naming / b. Names as descriptive
Part of the sense of a proper name is a criterion of the thing's identity [Hawley]
     Full Idea: A Fregean dictum is that part of the sense of proper name is a criterion of identity for the thing in question.
     From: Katherine Hawley (How Things Persist [2001], 3.8)
     A reaction: [She quotes Dummett 1981:545] We are asked to choose between this and the Kripke rigid/dubbing/causal account, with effectively no content.
5. Theory of Logic / G. Quantification / 3. Objectual Quantification
The universal quantifier can't really mean 'all', because there is no universal set [Hart,WD]
     Full Idea: All the main set theories deny that there is a set of which everything is a member. No interpretation has a domain with everything in it. So the universal quantifier never gets to mean everything all at once; 'all' does not mean all.
     From: William D. Hart (The Evolution of Logic [2010], 4)
     A reaction: Could you have an 'uncompleted' universal set, in the spirit of uncompleted infinities? In ordinary English we can talk about 'absolutely everything' - we just can't define a set of everything. Must we 'define' our domain?
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
Modern model theory begins with the proof of Los's Conjecture in 1962 [Hart,WD]
     Full Idea: The beginning of modern model theory was when Morley proved Los's Conjecture in 1962 - that a complete theory in a countable language categorical in one uncountable cardinal is categorical in all.
     From: William D. Hart (The Evolution of Logic [2010], 9)
Model theory studies how set theory can model sets of sentences [Hart,WD]
     Full Idea: Modern model theory investigates which set theoretic structures are models for which collections of sentences.
     From: William D. Hart (The Evolution of Logic [2010], 4)
     A reaction: So first you must choose your set theory (see Idea 13497). Then you presumably look at how to formalise sentences, and then look at the really tricky ones, many of which will involve various degrees of infinity.
Model theory is mostly confined to first-order theories [Hart,WD]
     Full Idea: There is no developed methematics of models for second-order theories, so for the most part, model theory is about models for first-order theories.
     From: William D. Hart (The Evolution of Logic [2010], 9)
Models are ways the world might be from a first-order point of view [Hart,WD]
     Full Idea: Models are ways the world might be from a first-order point of view.
     From: William D. Hart (The Evolution of Logic [2010], 9)
5. Theory of Logic / K. Features of Logics / 6. Compactness
First-order logic is 'compact': consequences of a set are consequences of a finite subset [Hart,WD]
     Full Idea: First-order logic is 'compact', which means that any logical consequence of a set (finite or infinite) of first-order sentences is a logical consequence of a finite subset of those sentences.
     From: William D. Hart (The Evolution of Logic [2010], 3)
5. Theory of Logic / L. Paradox / 4. Paradoxes in Logic / c. Berry's paradox
Berry's Paradox: we succeed in referring to a number, with a term which says we can't do that [Hart,WD]
     Full Idea: Berry's Paradox: by the least number principle 'the least number denoted by no description of fewer than 79 letters' exists, but we just referred to it using a description of 77 letters.
     From: William D. Hart (The Evolution of Logic [2010], 3)
     A reaction: I struggle with this. If I refer to 'an object to which no human being could possibly refer', have I just referred to something? Graham Priest likes this sort of idea.
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / c. Burali-Forti's paradox
The Burali-Forti paradox is a crisis for Cantor's ordinals [Hart,WD]
     Full Idea: The Burali-Forti Paradox was a crisis for Cantor's theory of ordinal numbers.
     From: William D. Hart (The Evolution of Logic [2010], 3)
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / a. The Liar paradox
The machinery used to solve the Liar can be rejigged to produce a new Liar [Hart,WD]
     Full Idea: In effect, the machinery introduced to solve the liar can always be rejigged to yield another version the liar.
     From: William D. Hart (The Evolution of Logic [2010], 4)
     A reaction: [He cites Hans Herzberger 1980-81] The machinery is Tarski's device of only talking about sentences of a language by using a 'metalanguage'.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
The less-than relation < well-orders, and partially orders, and totally orders the ordinal numbers [Hart,WD]
     Full Idea: We can show (using the axiom of choice) that the less-than relation, <, well-orders the ordinals, ...and that it partially orders the ordinals, ...and that it totally orders the ordinals.
     From: William D. Hart (The Evolution of Logic [2010], 1)
The axiom of infinity with separation gives a least limit ordinal ω [Hart,WD]
     Full Idea: The axiom of infinity with separation yields a least limit ordinal, which is called ω.
     From: William D. Hart (The Evolution of Logic [2010], 3)
There are at least as many infinite cardinals as transfinite ordinals (because they will map) [Hart,WD]
     Full Idea: Since we can map the transfinite ordinals one-one into the infinite cardinals, there are at least as many infinite cardinals as transfinite ordinals.
     From: William D. Hart (The Evolution of Logic [2010], 1)
Von Neumann's ordinals generalise into the transfinite better, because Zermelo's ω is a singleton [Hart,WD]
     Full Idea: It is easier to generalize von Neumann's finite ordinals into the transfinite. All Zermelo's nonzero finite ordinals are singletons, but if ω were a singleton it is hard to see how if could fail to be the successor of its member and so not a limit.
     From: William D. Hart (The Evolution of Logic [2010], 3)
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
19th century arithmetization of analysis isolated the real numbers from geometry [Hart,WD]
     Full Idea: The real numbers were not isolated from geometry until the arithmetization of analysis during the nineteenth century.
     From: William D. Hart (The Evolution of Logic [2010], 1)
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
We can establish truths about infinite numbers by means of induction [Hart,WD]
     Full Idea: Mathematical induction is a way to establish truths about the infinity of natural numbers by a finite proof.
     From: William D. Hart (The Evolution of Logic [2010], 5)
     A reaction: If there are truths about infinities, it is very tempting to infer that the infinities must therefore 'exist'. A nice, and large, question in philosophy is whether there can be truths without corresponding implications of existence.
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
Euclid has a unique parallel, spherical geometry has none, and saddle geometry has several [Hart,WD]
     Full Idea: There is a familiar comparison between Euclid (unique parallel) and 'spherical' geometry (no parallel) and 'saddle' geometry (several parallels).
     From: William D. Hart (The Evolution of Logic [2010], 2)
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
Mathematics makes existence claims, but philosophers usually say those are never analytic [Hart,WD]
     Full Idea: The thesis that no existence proposition is analytic is one of the few constants in philosophical consciences, but there are many existence claims in mathematics, such as the infinity of primes, five regular solids, and certain undecidable propositions.
     From: William D. Hart (The Evolution of Logic [2010], 2)
7. Existence / C. Structure of Existence / 5. Supervenience / d. Humean supervenience
A homogeneous rotating disc should be undetectable according to Humean supervenience [Hawley]
     Full Idea: Imagine a perfectly homogeneous non-atomistic disc. A record of all the non-relational information about the world at that moment will not reveal whether the disc is rotating about a vertical axis through. This tells against Humean supervenience.
     From: Katherine Hawley (How Things Persist [2001], 3.2)
     A reaction: [Armstrong 1980 originated this, and it is famously discussed by Kripke in lectures] There will, of course, be dispositions present because of the rotation, but Lewis excludes any such modal truths.
7. Existence / C. Structure of Existence / 8. Stuff / a. Pure stuff
Mass words do not have plurals, or numerical adjectives, or use 'fewer' [Hart,WD]
     Full Idea: Jespersen calls a noun a mass word when it has no plural, does not take numerical adjectives, and does not take 'fewer'.
     From: William D. Hart (The Evolution of Logic [2010], 3)
     A reaction: Jespersen was a great linguistics expert.
7. Existence / D. Theories of Reality / 10. Vagueness / b. Vagueness of reality
Non-linguistic things cannot be indeterminate, because they don't have truth-values at all [Hawley]
     Full Idea: Non-linguistic objects, properties, and states of affairs cannot be indeterminate because they cannot have determinate truth-values either. No cloud is indeterminate, just as no cloud is either determinately true or determinately false.
     From: Katherine Hawley (How Things Persist [2001], 4.1)
     A reaction: If vagueness must be linguistic, this means animals can never experience it, which I doubt. Presumably 'this is a cloud' is only made vague by the vagueness of the object, rather than by the vagueness of the sentence?
Maybe for the world to be vague, it must be vague in its foundations? [Hawley]
     Full Idea: There is a question of whether there must be 'vagueness all the way down' for the world to be vague. One view is that if there is a base level of precisely describably facts, upon which all the others supervene, then the world is not really vague.
     From: Katherine Hawley (How Things Persist [2001], 4.5)
     A reaction: My understanding of the physics is that it is non-vague all the way down, and then you get to the base level which is hopelessly vague!
7. Existence / D. Theories of Reality / 10. Vagueness / c. Vagueness as ignorance
Epistemic vagueness seems right in the case of persons [Hawley]
     Full Idea: The epistemic account of vagueness is particularly attractive where persons are concerned.
     From: Katherine Hawley (How Things Persist [2001], 4.14)
     A reaction: You'll have to see her text for details. Interesting that there might be different views of what vagueness is for different cases. Or putting it another way, absolutely everything (said, thought, existing or done) might be vague in some way!
7. Existence / D. Theories of Reality / 10. Vagueness / f. Supervaluation for vagueness
Supervaluation refers to one vaguely specified thing, through satisfaction by everything in some range [Hawley]
     Full Idea: Supervaluationists take a present-tense predication as concerning a single, but vaguely specified, moment. …It is indeterminate which of a range of moments enters into the truth conditions, but it is true if satisfied by every member of the range.
     From: Katherine Hawley (How Things Persist [2001], 2.7)
     A reaction: She is discussing stage theory, but this is a helpful clarification of the idea of supervaluation. Something can be satisfied by a whole bunch of values, even though you are not sure which one.
Supervaluationism takes what the truth-value would have been if indecision was resolved [Hawley]
     Full Idea: A supervaluationist approach involves consideration of what the truth value of the utterance would have been if semantic indecision had been resolved in this way or that.
     From: Katherine Hawley (How Things Persist [2001], 4.1)
     A reaction: At last, a lovely account of supervaluation in plain English that anyone can understand! Why don't they all do that? Well, done Katherine Hawley! ['semantic indecision' is uncertainty about what your words mean!]
8. Modes of Existence / B. Properties / 1. Nature of Properties
Maybe the only properties are basic ones like charge, mass and spin [Hawley]
     Full Idea: Some philosophers suspect that properties are few and far between, that there are only properties like charge, mass, spin, and so on.
     From: Katherine Hawley (How Things Persist [2001], 5.1)
     A reaction: I think properties are very sparse, and mainly consist of physical powers, but I am not sure what I think of this. It may be 'mere semantics'. Complex properties still seem to be properties. Powers combine to make properties, I suggest.
9. Objects / A. Existence of Objects / 1. Physical Objects
An object is 'natural' if its stages are linked by certain non-supervenient relations [Hawley]
     Full Idea: I suggest that our distinction between natural and unnatural (gerrymandered) objects corresponds to a distinction between series of stages which are and are not linked by certain non-supervenient relations.
     From: Katherine Hawley (How Things Persist [2001], 5.5)
     A reaction: See Idea 16213 for the nature of these 'relations'. I don't understand how an abstraction (as I take it) like a relation can unify a physical object. A trout-turkey is unified by a relation of some sort. Hawley defends Stage Theory.
9. Objects / B. Unity of Objects / 3. Unity Problems / b. Cat and its tail
Are sortals spatially maximal - so no cat part is allowed to be a cat? [Hawley]
     Full Idea: Many philosophers believe that sortal predicates are spatially maximal - for example, that no cat can be a proper spatial part of a cat.
     From: Katherine Hawley (How Things Persist [2001], 2.1)
     A reaction: This sounds reasonable until you cut the tail off a cat. Presumably what remains is a cat? So presumably that smaller part was always a cat? Only essentialism can make sense of this! You can't just invent rules for sortals.
9. Objects / B. Unity of Objects / 3. Unity Problems / c. Statue and clay
The modal features of statue and lump are disputed; when does it stop being that statue? [Hawley]
     Full Idea: It is difficult to establish a consensus about the modal features of the statue and the lump. Could that statue be made of a different lump? Could that statue of Goliath have been spherical? Not a realistic statue of Goliath, but still the same statue?
     From: Katherine Hawley (How Things Persist [2001], 6)
     A reaction: The problem is with a wild wacky sculptor, who might say it is a statue of Goliath no matter what shape the lump takes. 'Goliath had a spherical character'. Sometimes we will say (pace Evans) it is 'roughly identical' to the original statue.
Perdurantists can adopt counterpart theory, to explain modal differences of identical part-sums [Hawley]
     Full Idea: Perdurance theory claims that lumps and statues differ modally whilst always being made of the same parts. A natural way to make this less mysterious is for perdurantists to adopt counterpart theory, where objects in different worlds are never identical.
     From: Katherine Hawley (How Things Persist [2001], 6.2)
     A reaction: This, of course, is exactly the system created by David Lewis. Personally I rather like counterparts, but perdurance seems a tad crazy.
9. Objects / B. Unity of Objects / 3. Unity Problems / e. Vague objects
Vagueness is either in our knowledge, in our talk, or in reality [Hawley]
     Full Idea: There are three main views of vagueness: the Epistemic view says we talk precisely, but don't know what we talk precisely about; the Semantic view is that it is loose talk, or semantic indecision; the Ontic view says it is part of how the world is.
     From: Katherine Hawley (How Things Persist [2001], 4.1)
     A reaction: [My summary of two paragraphs] She associates Williamson with the first view, Lewis with the second, and Van Inwagen with the third.
Indeterminacy in objects and in properties are not distinct cases [Hawley]
     Full Idea: There is no important distinction to be drawn between cases where indeterminacy is due to the object involved and cases where indeterminacy is due to the property involved.
     From: Katherine Hawley (How Things Persist [2001], 4.2)
     A reaction: You could always paraphrase the object's situation propertywise, or the property's situation objectwise. 'His baldness is indeterminate'; 'where does the mountainous terrain end?'
9. Objects / C. Structure of Objects / 6. Constitution of an Object
The constitution theory is endurantism plus more than one object in a place [Hawley]
     Full Idea: Constitution theorists are endurance theorists who believe that there can be more than one object exactly occupying a spatial region at a certain moment.
     From: Katherine Hawley (How Things Persist [2001], 5.1)
     A reaction: I increasingly think that this is a ridiculous view. The constitution of an object isn't a further object. A constitution is a necessary requirement for a physical object. Hylomorphism! Constitutions can't be separate - they must constitute something!
Constitution theory needs sortal properties like 'being a sweater' to distinguish it from its thread [Hawley]
     Full Idea: Constitution theorists need to posit sortal properties of 'being a thread' or 'being a sweater', as grounds for the differences betwween the sweater and the thread that constitutes it.
     From: Katherine Hawley (How Things Persist [2001], 5.1)
     A reaction: This is further grounds for thinking the constitution view ridiculous, because there are no such properties. 'Being a sweater' is a category, which something belongs in if it has all the properties of a sweater. The final property triggers sweaterhood.
If the constitution view says thread and sweater are two things, why do we talk of one thing? [Hawley]
     Full Idea: The constitution theorists, who claim that the sweater and the thread are different things, should offer some explanation of why we tend to say that there is just one thing there. They must simply claim that we 'do not count by identity'.
     From: Katherine Hawley (How Things Persist [2001], 5.8)
     A reaction: Her example is a sweater knitted from a single piece of thread. Presumably we could count by sortal identity, so there is one thread here, and there is one sweater here. We just can't add the two together. No ontological arithmetic.
9. Objects / E. Objects over Time / 2. Objects that Change
'Adverbialism' explains change by saying an object has-at-some-time a given property [Hawley]
     Full Idea: Another strategy for the problem of change says that instantiation - the having of properties - is time-indexed, or relative to times, although properties themselves are not. This 'adverbialism' says that object has-at-t some property.
     From: Katherine Hawley (How Things Persist [2001], 1.5)
     A reaction: [She cites Johnson, Lowe and Haslanger for this] Promising. The question is whether the time index is attached to the object, to the property, or to the instantiation. The middle one is wrong. There aren't two properties - green-at-t1 and green-at-t2.
Presentism solves the change problem: the green banana ceases, so can't 'relate' to the yellow one [Hawley]
     Full Idea: Adopting presentism solves the problem of change, since it means that, once the banana is yellow, there just is no green banana, and the question of the relationship between yesterday's green banana and today's yellow one therefore does not arise.
     From: Katherine Hawley (How Things Persist [2001], 1.7)
     A reaction: Change remains kind of odd, but it is no longer the puzzlement of two things being the same when they are admitted to be different. There is only ever one thing. This is my preferred account, I think. I certainly hope past bananas don't exist.
The problem of change arises if there must be 'identity' of a thing over time [Hawley]
     Full Idea: It is the insistence on identity between objects wholly present at different times which gives rise to the problem of change.
     From: Katherine Hawley (How Things Persist [2001], 2.2)
     A reaction: My solution is to say things are the 'same', in a slightly loose non-transitive way, rather than formally identical, which is a concept from maths, not from reality.
9. Objects / E. Objects over Time / 3. Three-Dimensionalism
Endurance theory can relate properties to times, or timed instantiations to properties [Hawley]
     Full Idea: Endurance theory might claim a banana stands (atemporally) in different relations to different times (being-green-at to Monday), ..or has different instantiation relations to different properties (instantiates-on-Monday to being green).
     From: Katherine Hawley (How Things Persist [2001], 1.3)
     A reaction: She suggests that the first approach is more plausible for endurantists. I think she is right (assuming these are the only two options). Monday awaits a banana, but yellow doesn't.
Endurance is a sophisticated theory, covering properties, instantiation and time [Hawley]
     Full Idea: Endurance theory is not just a default 'no-theory' theory, for it must incorporate a sophisticated account of properties and instantiation, and requires a certain view of time if it is even to be formulable.
     From: Katherine Hawley (How Things Persist [2001], 1.8)
     A reaction: A bit odd to claim it is a sophisticated theory when it is held (at least in our culture) by absolutely everyone apart from a few philosophers and physicists. The sophistication may come with trying to describe it using current metaphysical vocabulary.
9. Objects / E. Objects over Time / 4. Four-Dimensionalism
How does perdurance theory explain our concern for our own future selves? [Hawley]
     Full Idea: A question for perdurance theory is whether it can account for the special concern we feel for our own future selves.
     From: Katherine Hawley (How Things Persist [2001], 1.8)
     A reaction: That is one of those questions that begins to look very mysterious whatever your theory. I favour endurantism, but me next year looks a very remote person for me to be concerned about, in comparison with the people around me now.
Perdurance needs an atemporal perspective, to say that the object 'has' different temporal parts [Hawley]
     Full Idea: Perdurance relies on our having an 'atemporal' perspective from which we can truly say a banana has both yellow and green parts, where this 'has' is not in the present tense. ..Perdurance theory cannot be expressed straightforwardly in the present tense.
     From: Katherine Hawley (How Things Persist [2001], 1.2)
     A reaction: This seems to require the tenseless B-series view of time. It seems to need a tenseless view of the past, but what does it have to say about the future?
If an object is the sum of all of its temporal parts, its mass is staggeringly large! [Hawley]
     Full Idea: The mass of an object is the sum of its nonoverlapping parts. Analogy would suggest that a persisting banana has, atemporally speaking, a mass that is the sum of all the masses of the 100g temporal parts, a worryingly large figure.
     From: Katherine Hawley (How Things Persist [2001], 2.1)
     A reaction: This is an objection to the Perdurance view that an object is the sum of all of its temporal parts. Their duration tends towards instantaneous, so the aggregate mass tends towards infinity. She says they should deny atemporal mass.
Perdurance says things are sums of stages; Stage Theory says each stage is the thing [Hawley]
     Full Idea: According to Perdurance Theory, it is long-lived sums of stages which are tennis balls, whereas according to Stage Theory, it is the stages themselves which are tennis balls.
     From: Katherine Hawley (How Things Persist [2001], 2.2)
     A reaction: These seem to be the two options if you are a four-dimensionalist, though Fine says you could be a weird three-dimensionalist and choose stage theory.
If a life is essentially the sum of its temporal parts, it couldn't be shorter or longer than it was? [Hawley]
     Full Idea: It seems that perdurance theory should identify Descartes with the sum of his temporal parts, but that means Descartes essentially lived for 54 years, which seems absurd, as he could have lived longer or less long than he in fact did.
     From: Katherine Hawley (How Things Persist [2001], 6.10)
     A reaction: [She credits Van Inwagen with this] I'm not clear why a counterpart of Descartes could not have a shorter or longer sum of parts, and still be Descartes. If the sum is rigidly designated, that is a problem for endurance too.
9. Objects / E. Objects over Time / 5. Temporal Parts
Stage Theory seems to miss out the link between stages of the same object [Hawley]
     Full Idea: The first worry for Stage Theory is that many present stages are bananas, and many stages tomorrow are bananas, but this seems to omit the important fact that some of those stages are intimately linked, that certain stages are the same banana.
     From: Katherine Hawley (How Things Persist [2001], 2.3)
     A reaction: Hawley has a theory to do with external relations, which I didn't find very persuasive. Just to say stages have a 'relation' seems too abstract. Stages of disparate things can also have 'relations', but presumably the wrong sort.
Stage Theory says every stage is a distinct object, which gives too many objects [Hawley]
     Full Idea: The second worry for Stage Theory is that there are far too many bananas in the world on this account.
     From: Katherine Hawley (How Things Persist [2001], 2.3)
     A reaction: The point is that each (instantaneous) stage is considered to be a whole banana (as opposed to one sum of all the stages of the banana, in the Perdurance view). A pretty serious problem, which she tries to deal with.
An isolated stage can't be a banana (which involves suitable relations to other stages) [Hawley]
     Full Idea: A single isolated stage could not be a banana, because in order to be a banana a stage must be suitably related to other stages with appropriate properties.
     From: Katherine Hawley (How Things Persist [2001], 3.4.1)
     A reaction: This seems at odds with the claim that each stage is the whole thing (rather than the long temporal 'worm' of perdurance theory). Isolated stages are instantaneous, so can't be anything, really. Her 'relations' seem hand-wavy to me. Connections?
Stages of one thing are related by extrinsic counterfactual and causal relations [Hawley]
     Full Idea: I claim that there are relations between the distinct stages of a persisting object which are not determined by the intrinsic properties of those stages. …The later stages depend, counterfactually and causally, upon the earlier stages.
     From: Katherine Hawley (How Things Persist [2001], 3.5)
     A reaction: This is the heart of her theory. How can there be a causal link between two stages which is not the result of intrinsic properties of the stages? This begins to sound like Malebranche's Occasionalism.
Stages must be as fine-grained in length as change itself, so any change is a new stage [Hawley]
     Full Idea: To account for change, stages and temporal parts must be as fine-grained as change: a material thing must have as many stages or parts as it is in incompatible states during its lifetime.
     From: Katherine Hawley (How Things Persist [2001], 2.4)
     A reaction: There seems to be a dilemma for stages here, of being so fat that they are divisible and change, or so thin that they barely exist. Lose-lose, I'd say.
The stages of Stage Theory seem too thin to populate the world, or to be referred to [Hawley]
     Full Idea: A third worry for Stage Theory is that the momentary stages themselves are just too thin to populate the world, and too thin to be the objects of reference.
     From: Katherine Hawley (How Things Persist [2001], 2.3)
     A reaction: Her three objections to her own theory add up to sufficient to refute it, in my view, though a large chunk of her book is spent trying to refute the objections.
9. Objects / F. Identity among Objects / 8. Leibniz's Law
If two things might be identical, there can't be something true of one and false of the other [Hawley]
     Full Idea: We can call the 'transference principle' the claim that if it is indeterminate whether two objects are identical, then nothing determinately true of one can be determinately false of the other.
     From: Katherine Hawley (How Things Persist [2001], 4.9)
     A reaction: The point is that Leibniz's Law could immediately be invoked to show there is no possibility of their identity.
10. Modality / E. Possible worlds / 3. Transworld Objects / c. Counterparts
To decide whether something is a counterpart, we need to specify a relevant sortal concept [Hawley]
     Full Idea: When asked whether a possible object is a counterpart of something, we need to specify which sortal we are interested in.
     From: Katherine Hawley (How Things Persist [2001], 6.2)
     A reaction: The compares this to the 'respect' in which two things are similar. For example, what would count as a counterpart of the current British Prime Minister? De re or de dicto reference?
12. Knowledge Sources / A. A Priori Knowledge / 2. Self-Evidence
Fregean self-evidence is an intrinsic property of basic truths, rules and definitions [Hart,WD]
     Full Idea: The conception of Frege is that self-evidence is an intrinsic property of the basic truths, rules, and thoughts expressed by definitions.
     From: William D. Hart (The Evolution of Logic [2010], p.350)
     A reaction: The problem is always that what appears to be self-evident may turn out to be wrong. Presumably the effort of arriving at a definition ought to clarify and support the self-evident ingredient.
12. Knowledge Sources / A. A Priori Knowledge / 11. Denying the A Priori
The failure of key assumptions in geometry, mereology and set theory throw doubt on the a priori [Hart,WD]
     Full Idea: In the case of the parallels postulate, Euclid's fifth axiom (the whole is greater than the part), and comprehension, saying was believing for a while, but what was said was false. This should make a shrewd philosopher sceptical about a priori knowledge.
     From: William D. Hart (The Evolution of Logic [2010], 2)
     A reaction: Euclid's fifth is challenged by infinite numbers, and comprehension is challenged by Russell's paradox. I can't see a defender of the a priori being greatly worried about these cases. No one ever said we would be right - in doing arithmetic, for example.
16. Persons / B. Nature of the Self / 7. Self and Body / a. Self needs body
What is sacred is not a person, but the whole physical human being [Weil]
     Full Idea: There is something sacred in every man, but it is not his person. Nor yet is it the human personality. It is this man; no more and no less. …It is he. The whole of him. The arms, they eyes, the thoughts, everything.
     From: Simone Weil (Human Personality [1943], p,70)
     A reaction: I take her to be referring to exactly the concept of a 'person' which Locke introduced. It is important to remember that his concept is mainly forensic - as a concept of ownership and contracts. A person is an abstraction. Even a corpse is a human.
16. Persons / D. Continuity of the Self / 5. Concerns of the Self
On any theory of self, it is hard to explain why we should care about our future selves [Hawley]
     Full Idea: It is rather difficult to say why one should care about one's future self, even on an endurance theory account of the self.
     From: Katherine Hawley (How Things Persist [2001], 3.9)
     A reaction: A nice passing remark, that strikes me forcibly as one of those basic mysteries of experience that philosophers can only gawp at, and have no theory to offer.
18. Thought / A. Modes of Thought / 1. Thought
The mind is imprisoned and limited by language, restricting our awareness of wider thoughts [Weil]
     Full Idea: At the very best, a mind is enclosed in language is in a prison. It is limited to the number of relations which words can make simultaneously present to it; and remains in ignorance of thoughts which involve the combination of a greater number.
     From: Simone Weil (Human Personality [1943], p.89)
     A reaction: This seems to be a germ of the type of view of language which blossoms in Derrida. But she is on to something. None of us grasp fully, I think, the non-linguistic nature of good thinking.
18. Thought / D. Concepts / 3. Ontology of Concepts / c. Fregean concepts
The Fregean concept of GREEN is a function assigning true to green things, and false to the rest [Hart,WD]
     Full Idea: A Fregean concept is a function that assigns to each object a truth value. So instead of the colour green, the concept GREEN assigns truth to each green thing, but falsity to anything else.
     From: William D. Hart (The Evolution of Logic [2010], 2)
     A reaction: This would seem to immediately hit the renate/cordate problem, if there was a world in which all and only the green things happened to be square. How could Frege then distinguish the green from the square? Compare Idea 8245.
21. Aesthetics / A. Aesthetic Experience / 6. The Sublime
Beauty is an attractive mystery, leaving nothing to be desired [Weil]
     Full Idea: Beauty is the supreme mystery of the world. It is a gleam which attracts the attention and yet does nothing to sustain it. …While exciting desire, it makes clear that there is nothing in it to be desired, because what we want is that it should not change.
     From: Simone Weil (Human Personality [1943], p.92)
     A reaction: She attributes beauty to a supernatural source. I catalogue this idea under 'the sublime', rather than 'beauty'. It may be better to say that beauty inspires love, rather than desire.
22. Metaethics / B. Value / 1. Nature of Value / f. Ultimate value
All we need are the unity of justice, truth and beauty [Weil]
     Full Idea: Justice, truth, and beauty are sisters and comrades. With three such beautiful words we have no need to look for any others.
     From: Simone Weil (Human Personality [1943], p.93)
     A reaction: The embodiment of platonist values. Without the platonist ontology, I like the identification of a few core values, and have always thought that Beauty, Goodness and Truth were a well chosen trio. Swapping 'justice' for 'goodness' is interesting.
22. Metaethics / B. Value / 2. Values / c. Life
The sacred in every human is their expectation of good rather than evil [Weil]
     Full Idea: At the bottom of every human heart …there is something that goes on indomitably expecting, in the teeth of all crimes committed, suffered and witnessed, that good and not evil will be done to him. It is this above all that is sacred in every human being.
     From: Simone Weil (Human Personality [1943], p.71)
     A reaction: I'm thinking that this expectation may come from having at least one loving parent, and failing that there are people who have no such expectation as adults. Simone obviously thinks the hope runs deeper than that.
22. Metaethics / B. Value / 2. Values / g. Love
Everything which originates in love is beautiful [Weil]
     Full Idea: Everything which originates from pure love is lit with the radiance of beauty.
     From: Simone Weil (Human Personality [1943], p.93)
     A reaction: I suppose if I found a counterexample, she would say that is not 'pure' love. This sentence leaves open the possibility of beauty in the absence of love (such as a beautiful face noticed in the street). In her case, can beauty and love be separated?
22. Metaethics / B. Value / 2. Values / j. Evil
Evil is transmitted by comforts and pleasures, but mostly by doing harm to people [Weil]
     Full Idea: One may transmit evil to a human being by flattering him or giving him comforts and pleasures; but most often men transmit evil to other men by doing them harm.
     From: Simone Weil (Human Personality [1943], p.94)
     A reaction: Some people receive harm very passively, especially if it is normal. What of tough love, which is erroneously seen as harm?
24. Political Theory / D. Ideologies / 8. Socialism
It is not more money which the wretched members of society need [Weil]
     Full Idea: Suppose the devil were bargaining for the soul of some wretch, and some pitying person said to the devil 'Shame on you, that commodity is worth twice as much'. Such is the sinister farce played by the working class unions, parties and intellectuals.
     From: Simone Weil (Human Personality [1943], p.80)
     A reaction: A striking thought. It is paradoxical when the working classes despise the middle classes, and yet aspire to be like them. It's hard to know what a mystic like Weil has in mind. An obvious thought is that the aspiration should be freedom, not money.
24. Political Theory / D. Ideologies / 9. Communism
The problem of the collective is not suppression of persons, but persons erasing themselves [Weil]
     Full Idea: The chief danger does not lie in the collectivity's tendency to circumscribe the person, but in the person's tendency to immolate himself in the collective.
     From: Simone Weil (Human Personality [1943], p.78)
     A reaction: I'm guessing that in 1943 she had in mind both Nazis and Communists. She seems to articulate a strong form of liberalism in an interesting way. It sounds like a form of Bad Faith.
25. Social Practice / B. Equalities / 1. Grounds of equality
People absurdly claim an equal share of things which are essentially privileged [Weil]
     Full Idea: To the dimmed understanding of our age there seems nothing odd in claiming an equal share of privilege for everybody - an equal share in things whose essence is privilege.
     From: Simone Weil (Human Personality [1943], p.84)
     A reaction: Not sure what she has in mind. Probably not the finest food and drink. I suppose she is attacking the modern egalitarian view of democratic society. What things have privilege as their 'essence'? Being a 'winner'? Interesting, though.
25. Social Practice / C. Rights / 1. Basis of Rights
Rights are asserted contentiously, and need the backing of force [Weil]
     Full Idea: Rights are always asserted in a tone of contention; and when this tone is adopted, it must rely upon force in the background, or else it will be laughed at.
     From: Simone Weil (Human Personality [1943], p.81)
     A reaction: This is the sort of observation which leads on to Foucault's account of all-pervasive power. Her observation may not be so sinister. It is obvious that introductions of new rights go against the grain of a conservative society - and so need a push.
Giving centrality to rights stifles all impulses of charity [Weil]
     Full Idea: To place the notion of rights at the centre of social conflicts is to inhibit any possible impulse of charity on both sides.
     From: Simone Weil (Human Personality [1943], p.83)
     A reaction: I think she exaggerates. To place personal charity at the centre of social conflicts strikes me as extremely conservative, and unlikely to improve the situation very much. I'm unsure how to reconcile this with Idea 23750. What sort of charity?
25. Social Practice / D. Justice / 1. Basis of justice
The spirit of justice needs the full attention of truth, and that attention is love [Weil]
     Full Idea: Because affliction and truth need the same kind of attention …the spirit of justice and the spirit of truth are one. The spirit of justice and truth is nothing else be a certain kind of attention, which is pure love.
     From: Simone Weil (Human Personality [1943], p.92)
     A reaction: I'm not sure about this as an observation, but as an inspiration it is very appealing, and (as so often with Weil) strikingly and attractively independent. I prefer love to arise naturally, rather than be a product of exhortation.
Justice (concerning harm) is distinct from rights (concerning inequality) [Weil]
     Full Idea: Justice is seeing that no harm is done to men. When a man cries inwardly 'Why am I being hurt?' he is being harmed. The other cry of 'Why have others got more than me?' refers to rights. We must distinguish them, and hush the second with law.
     From: Simone Weil (Human Personality [1943], p.93)
     A reaction: Her great passion is for justice, and so she downplays rights. The simple 'why am I being hurt?' has a horrible resonance in 1943. What of the hurts of disease? Are they unjust?
25. Social Practice / D. Justice / 3. Punishment / d. Reform of offenders
The only thing in society worse than crime is repressive justice [Weil]
     Full Idea: There is one, and only one, thing in society more hideous than crime - namely, repressive justice.
     From: Simone Weil (Human Personality [1943], p.95)
     A reaction: Presumably fans of 'repressive' justice would describe it as 'reformative' justice. In general, one of the most hideous parts of historical human societies has been the punishments they dished out (simply because they had the power to do it).
Punishment aims at the good for men who don't desire it [Weil]
     Full Idea: Punishment is solely a method of procuring pure good for men who do not desire it. The art of punishing is the art of awakening in a criminal, by pain or even death, the desire for pure good.
     From: Simone Weil (Human Personality [1943], p.95)
     A reaction: I know Weil is seen as some sort of saint, but this remark could have come from the Inquisition. I'm always alarmed by talk of 'pure' good and 'pure' evil, which seem to need a superior insight the rest of us lack. But see Idea 23764.
26. Natural Theory / C. Causation / 9. General Causation / c. Counterfactual causation
Causation is nothing more than the counterfactuals it grounds? [Hawley]
     Full Idea: Counterfactual accounts of causation say that a causal connection is exhausted by the counterfactuals it appears to ground.
     From: Katherine Hawley (How Things Persist [2001], 3.5)
     A reaction: I am bewildered as to how this became a respectable view in philosophy. I quite understand that this might exhaust the 'logic' of causal relations. Presumably you can have counterfactuals in mathematics which are not causal?
27. Natural Reality / D. Time / 3. Parts of Time / b. Instants
Time could be discrete (like integers) or dense (rationals) or continuous (reals) [Hawley]
     Full Idea: There seem to be three possible ways for time to be fine-grained. The ordering of instants could be discrete (like the integers), dense (like the rational numbers) or continuous (like the real numbers).
     From: Katherine Hawley (How Things Persist [2001], 2.5)
     A reaction: She seems to assume that time must be 'grained', but I would take the continuous view to imply that there is no grain at all (which is bad news for her version of stage theory).
28. God / A. Divine Nature / 6. Divine Morality / c. God is the good
The only choice is between supernatural good, or evil [Weil]
     Full Idea: In all the crucial problems of human existence the only choice is between supernatural good on the one hand and evil on the other.
     From: Simone Weil (Human Personality [1943], p.86)
     A reaction: This idea strikes me as absurd, but I include it for a fuller picture of Simone Weil. Aristotle (my hero) is referred to, and labelled as more stupid than a village idiot.