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All the ideas for 'Possibility', 'A Mathematical Introduction to Logic (2nd)' and 'Quaestiones de Potentia Dei'

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61 ideas

1. Philosophy / F. Analytic Philosophy / 4. Conceptual Analysis
If an analysis shows the features of a concept, it doesn't seem to 'reduce' the concept [Jubien]
     Full Idea: An analysis of a concept tells us what the concept is by telling us what its constituents are and how they are combined. ..The features of the concept are present in the analysis, making it surprising the 'reductive' analyses are sought.
     From: Michael Jubien (Possibility [2009], 4.5)
     A reaction: He says that there are nevertheless reductive analyses, such as David Lewis's analysis of modality. We must disentangle conceptual analysis from causal analysis (e.g. in his example of the physicalist reduction of mind).
4. Formal Logic / B. Propositional Logic PL / 3. Truth Tables
Until the 1960s the only semantics was truth-tables [Enderton]
     Full Idea: Until the 1960s standard truth-table semantics were the only ones that there were.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], 1.10.1)
     A reaction: The 1960s presumably marked the advent of possible worlds.
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / a. Symbols of ST
'dom R' indicates the 'domain' of objects having a relation [Enderton]
     Full Idea: 'dom R' indicates the 'domain' of a relation, that is, the set of all objects that are members of ordered pairs and that have that relation.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
'fld R' indicates the 'field' of all objects in the relation [Enderton]
     Full Idea: 'fld R' indicates the 'field' of a relation, that is, the set of all objects that are members of ordered pairs on either side of the relation.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
'ran R' indicates the 'range' of objects being related to [Enderton]
     Full Idea: 'ran R' indicates the 'range' of a relation, that is, the set of all objects that are members of ordered pairs and that are related to by the first objects.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
We write F:A→B to indicate that A maps into B (the output of F on A is in B) [Enderton]
     Full Idea: We write F : A → B to indicate that A maps into B, that is, the domain of relating things is set A, and the things related to are all in B. If we add that F = B, then A maps 'onto' B.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
'F(x)' is the unique value which F assumes for a value of x [Enderton]
     Full Idea: F(x) is a 'function', which indicates the unique value which y takes in ∈ F. That is, F(x) is the value y which F assumes at x.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / b. Terminology of ST
A relation is 'symmetric' on a set if every ordered pair has the relation in both directions [Enderton]
     Full Idea: A relation is 'symmetric' on a set if every ordered pair in the set has the relation in both directions.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
A relation is 'transitive' if it can be carried over from two ordered pairs to a third [Enderton]
     Full Idea: A relation is 'transitive' on a set if the relation can be carried over from two ordered pairs to a third.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
The 'powerset' of a set is all the subsets of a given set [Enderton]
     Full Idea: The 'powerset' of a set is all the subsets of a given set. Thus: PA = {x : x ⊆ A}.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
Two sets are 'disjoint' iff their intersection is empty [Enderton]
     Full Idea: Two sets are 'disjoint' iff their intersection is empty (i.e. they have no members in common).
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
A 'domain' of a relation is the set of members of ordered pairs in the relation [Enderton]
     Full Idea: The 'domain' of a relation is the set of all objects that are members of ordered pairs that are members of the relation.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
A 'relation' is a set of ordered pairs [Enderton]
     Full Idea: A 'relation' is a set of ordered pairs. The ordering relation on the numbers 0-3 is captured by - in fact it is - the set of ordered pairs {<0,1>,<0,2>,<0,3>,<1,2>,<1,3>,<2,3>}.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
     A reaction: This can't quite be a definition of order among numbers, since it relies on the notion of a 'ordered' pair.
A 'function' is a relation in which each object is related to just one other object [Enderton]
     Full Idea: A 'function' is a relation which is single-valued. That is, for each object, there is only one object in the function set to which that object is related.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
A function 'maps A into B' if the relating things are set A, and the things related to are all in B [Enderton]
     Full Idea: A function 'maps A into B' if the domain of relating things is set A, and the things related to are all in B.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
A function 'maps A onto B' if the relating things are set A, and the things related to are set B [Enderton]
     Full Idea: A function 'maps A onto B' if the domain of relating things is set A, and the things related to are set B.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
A relation is 'reflexive' on a set if every member bears the relation to itself [Enderton]
     Full Idea: A relation is 'reflexive' on a set if every member of the set bears the relation to itself.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
A relation satisfies 'trichotomy' if all pairs are either relations, or contain identical objects [Enderton]
     Full Idea: A relation satisfies 'trichotomy' on a set if every ordered pair is related (in either direction), or the objects are identical.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
A set is 'dominated' by another if a one-to-one function maps the first set into a subset of the second [Enderton]
     Full Idea: A set is 'dominated' by another if a one-to-one function maps the first set into a subset of the second.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
4. Formal Logic / F. Set Theory ST / 3. Types of Set / e. Equivalence classes
An 'equivalence relation' is a reflexive, symmetric and transitive binary relation [Enderton]
     Full Idea: An 'equivalence relation' is a binary relation which is reflexive, and symmetric, and transitive.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
We 'partition' a set into distinct subsets, according to each relation on its objects [Enderton]
     Full Idea: Equivalence classes will 'partition' a set. That is, it will divide it into distinct subsets, according to each relation on the set.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], Ch.0)
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
Inference not from content, but from the fact that it was said, is 'conversational implicature' [Enderton]
     Full Idea: The process is dubbed 'conversational implicature' when the inference is not from the content of what has been said, but from the fact that it has been said.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], 1.7.3)
5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
It is a mistake to think that the logic developed for mathematics can clarify language and philosophy [Jubien]
     Full Idea: It has often been uncritically assumed that logic that was initially a tool for clarifying mathematics could be seamlessly and uniformly applied in the effort to clarify ordinary language and philosophy, but this has been a real mistake.
     From: Michael Jubien (Possibility [2009], Intro)
     A reaction: I'm not saying he's right (since you need stupendous expertise to make that call) but my intuitions are that he has a good point, and he is at least addressing a crucial question which most analytical philosophers avert their eyes from.
5. Theory of Logic / B. Logical Consequence / 2. Types of Consequence
Validity is either semantic (what preserves truth), or proof-theoretic (following procedures) [Enderton]
     Full Idea: The point of logic is to give an account of the notion of validity,..in two standard ways: the semantic way says that a valid inference preserves truth (symbol |=), and the proof-theoretic way is defined in terms of purely formal procedures (symbol |-).
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], 1.1.3..)
     A reaction: This division can be mirrored in mathematics, where it is either to do with counting or theorising about things in the physical world, or following sets of rules from axioms. Language can discuss reality, or play word-games.
5. Theory of Logic / F. Referring in Logic / 1. Naming / a. Names
We only grasp a name if we know whether to apply it when the bearer changes [Jubien]
     Full Idea: We cannot be said to have a full grasp of a name unless we have a definite disposition to apply it or to withhold it under whatever conceivable changes the bearer of the name might come to undergo.
     From: Michael Jubien (Possibility [2009], 5.3)
     A reaction: This is right, and an excellent counterproposal to the logicians' notion that names have to rigidly designate. As a bare minimum, you are not supposed to deny the identity of your parents because they have grown a bit older, or a damaged painting.
The baptiser picks the bearer of a name, but social use decides the category [Jubien]
     Full Idea: The person who introduces a proper name gets to pick its bearer, but its category - and consequently the meaning of the name - is determined by social use.
     From: Michael Jubien (Possibility [2009], 7)
     A reaction: New 'division of labour'. The idea that a name has some sort of meaning seems right and important. If babies were switched after baptism, social use might fix the name to the new baby. The namer could stipulate the category at the baptism. Too neat.
5. Theory of Logic / F. Referring in Logic / 1. Naming / c. Names as referential
Examples show that ordinary proper names are not rigid designators [Jubien]
     Full Idea: There are plenty of examples to show that ordinary proper names simply are not rigid designators.
     From: Michael Jubien (Possibility [2009], 5.1)
     A reaction: His examples are the planet Venus and the dust of which it is formed, and a statue made of clay. In other words, for some objects, perhaps under certain descriptions (e.g. functional ones), the baptised matter can change. Rigidity is an extra topping.
5. Theory of Logic / F. Referring in Logic / 2. Descriptions / b. Definite descriptions
We could make a contingent description into a rigid and necessary one by adding 'actual' to it [Jubien]
     Full Idea: 'The winner of the Derby' satisfies some horse, but only accidentally. But we could 'rigidify' the description by inserting 'actual' into it, giving 'the actual winner of the Derby'. Winning is a contingent property, but actually winning is necessary.
     From: Michael Jubien (Possibility [2009], 5.1)
     A reaction: I like this unusual proposal because instead of switching into formal logic in order to capture the ideas we are after, he is drawing on the resources of ordinary language, offering philosophers a way of speaking plain English more precisely.
5. Theory of Logic / G. Quantification / 3. Objectual Quantification
Philosophers reduce complex English kind-quantifiers to the simplistic first-order quantifier [Jubien]
     Full Idea: There is a readiness of philosophers to 'translate' English, with its seeming multitude of kind-driven quantifiers, into first-order logic, with its single wide-open quantifier.
     From: Michael Jubien (Possibility [2009], 4.1)
     A reaction: As in example he says that reference to a statue involves a 'statue-quantifier'. Thus we say things about the statue that we would not say about the clay, which would involve a 'clay-quantifier'.
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
A logical truth or tautology is a logical consequence of the empty set [Enderton]
     Full Idea: A is a logical truth (tautology) (|= A) iff it is a semantic consequence of the empty set of premises (φ |= A), that is, every interpretation makes A true.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], 1.3.4)
     A reaction: So the final column of every line of the truth table will be T.
5. Theory of Logic / I. Semantics of Logic / 4. Satisfaction
A truth assignment to the components of a wff 'satisfy' it if the wff is then True [Enderton]
     Full Idea: A truth assignment 'satisfies' a formula, or set of formulae, if it evaluates as True when all of its components have been assigned truth values.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], 1.2)
     A reaction: [very roughly what Enderton says!] The concept becomes most significant when a large set of wff's is pronounced 'satisfied' after a truth assignment leads to them all being true.
5. Theory of Logic / K. Features of Logics / 3. Soundness
A proof theory is 'sound' if its valid inferences entail semantic validity [Enderton]
     Full Idea: If every proof-theoretically valid inference is semantically valid (so that |- entails |=), the proof theory is said to be 'sound'.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], 1.1.7)
5. Theory of Logic / K. Features of Logics / 4. Completeness
A proof theory is 'complete' if semantically valid inferences entail proof-theoretic validity [Enderton]
     Full Idea: If every semantically valid inference is proof-theoretically valid (so that |= entails |-), the proof-theory is said to be 'complete'.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], 1.1.7)
5. Theory of Logic / K. Features of Logics / 6. Compactness
Proof in finite subsets is sufficient for proof in an infinite set [Enderton]
     Full Idea: If a wff is tautologically implied by a set of wff's, it is implied by a finite subset of them; and if every finite subset is satisfiable, then so is the whole set of wff's.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], 2.5)
     A reaction: [Enderton's account is more symbolic] He adds that this also applies to models. It is a 'theorem' because it can be proved. It is a major theorem in logic, because it brings the infinite under control, and who doesn't want that?
5. Theory of Logic / K. Features of Logics / 7. Decidability
Expressions are 'decidable' if inclusion in them (or not) can be proved [Enderton]
     Full Idea: A set of expressions is 'decidable' iff there exists an effective procedure (qv) that, given some expression, will decide whether or not the expression is included in the set (i.e. doesn't contradict it).
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], 1.7)
     A reaction: This is obviously a highly desirable feature for a really reliable system of expressions to possess. All finite sets are decidable, but some infinite sets are not.
5. Theory of Logic / K. Features of Logics / 8. Enumerability
For a reasonable language, the set of valid wff's can always be enumerated [Enderton]
     Full Idea: The Enumerability Theorem says that for a reasonable language, the set of valid wff's can be effectively enumerated.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], 2.5)
     A reaction: There are criteria for what makes a 'reasonable' language (probably specified to ensure enumerability!). Predicates and functions must be decidable, and the language must be finite.
7. Existence / A. Nature of Existence / 3. Being / g. Particular being
To exist necessarily is to have an essence whose own essence must be instantiated [Jubien]
     Full Idea: For a thing to exist necessarily is for it to have an entity-essence whose own entity-essence entails being instantiated.
     From: Michael Jubien (Possibility [2009], 6.4)
     A reaction: This is the culmination of a lengthy discussion, and is not immediately persuasive. For Jubien the analysis rests on a platonist view of properties, which doesn't help.
7. Existence / C. Structure of Existence / 8. Stuff / a. Pure stuff
If objects are just conventional, there is no ontological distinction between stuff and things [Jubien]
     Full Idea: Under the Quinean (conventional) view of objects, there is no ontological distinction between stuff and things.
     From: Michael Jubien (Possibility [2009], 1.5)
     A reaction: This is the bold nihilistic account of physical objects, which seems to push all of our ontology into language (English?). We could devise divisions into things that were just crazy, and likely to lead to the rapid extinction of creatures who did it.
7. Existence / E. Categories / 1. Categories
The category of Venus is not 'object', or even 'planet', but a particular class of good-sized object [Jubien]
     Full Idea: The category of Venus is not 'physical object' or 'mereological sum', but narrower. Surprisingly, it is not 'planet', since it might cease to be a planet and still merit the name 'Venus'. It is something like 'well-integrated, good-sized physical object'.
     From: Michael Jubien (Possibility [2009], 5.3)
     A reaction: Jubien is illustrating Idea 13402. This is a nice demonstration of how one might go about the task of constructing categories - by showing the modal profiles of things to which names have been assigned. Categories are file names.
9. Objects / A. Existence of Objects / 5. Individuation / a. Individuation
The idea that every entity must have identity conditions is an unfortunate misunderstanding [Jubien]
     Full Idea: The pervasiveness, throughout philosophy, of the assumption that entities of various kinds need identity conditions is one unfortunate aspect of Quine's important philosophical legacy.
     From: Michael Jubien (Possibility [2009], Intro)
     A reaction: Lowe seems to be an example of a philosopher who habitually demands individuation conditions for everything that is referred to. Presumably the alternative is to take lots of things as primitive, but this seems to be second best.
9. Objects / A. Existence of Objects / 5. Individuation / d. Individuation by haecceity
Any entity has the unique property of being that specific entity [Jubien]
     Full Idea: For any entity of any sort, abstract or concrete, I assume there is a property of being that specific entity. For want of a better term, I will call such properties entity-essences. They are 'singulary' - not instantiable by more than one thing at a time.
     From: Michael Jubien (Possibility [2009], 4.2)
     A reaction: Baffling. Why would someone who has mocked all sorts of bogus philosophical claims based on logic then go on to assert the existence of such weird things as these? I can't make sense of this property being added to a thing's other properties.
9. Objects / A. Existence of Objects / 5. Individuation / e. Individuation by kind
It is incoherent to think that a given entity depends on its kind for its existence [Jubien]
     Full Idea: It is simply far-fetched - even incoherent - to think that, given an entity, of whatever kind, its being a single entity somehow consists in its satisfying some condition involving the kind to which it belongs (or concepts related to that kind).
     From: Michael Jubien (Possibility [2009], 2.3)
     A reaction: Well said. I can't see how philosophers have allowed themselves to drift into such a daft view. Kinds blatantly depend on the individuals that constitute them, so how could the identity of the individuals depend on their kind?
9. Objects / A. Existence of Objects / 6. Nihilism about Objects
Objects need conventions for their matter, their temporal possibility, and their spatial possibility [Jubien]
     Full Idea: We need a first convention to determine what matter constitutes objects, then a second to determine whether there are different temporal possibilities for a given object, then a third for different spatial possibilities.
     From: Michael Jubien (Possibility [2009], 1.5)
     A reaction: This is building up a Quinean account of objects, as mere matter in regions of spacetime, which are then precisely determined by a set of social conventions.
Basically, the world doesn't have ready-made 'objects'; we carve objects any way we like [Jubien]
     Full Idea: There is a certain - very mild - sense in which I don't think the physical world comes with ready-made objects. I think instead that we (conventionally) carve it up into objects, and this can be done any way we like.
     From: Michael Jubien (Possibility [2009], 1.5)
     A reaction: I have no idea how one could begin to refute such a view. Obviously there are divisions (even if only of physical density) in the world, but nothing obliges us to make divisions at those points. We happily accept objects with gaps in them.
9. Objects / B. Unity of Objects / 1. Unifying an Object / b. Unifying aggregates
'One' can mean undivided and not a multitude, or it can add measurement, giving number [Aquinas]
     Full Idea: There are two sorts of one. There is the one which is convertible with being, which adds nothing to being except being undivided; and this deprives of multitude. Then there is the principle of number, which to the notion of being adds measurement.
     From: Thomas Aquinas (Quaestiones de Potentia Dei [1269], q3 a16 ad 3-um)
     A reaction: [From a lecture handout] I'm not sure I understand this. We might say, I suppose, that insofar as water is water, it is all one, but you can't count it. Perhaps being 'unified' and being a 'unity' are different?
9. Objects / B. Unity of Objects / 3. Unity Problems / c. Statue and clay
If the statue is loved and the clay hated, that is about the object first qua statue, then qua clay [Jubien]
     Full Idea: If a sculptor says 'I love the statue but I really hate that piece of clay - it is way too hard to work with' ...the statement is partly is partly about that object qua statue and partly about that object qua piece of clay.
     From: Michael Jubien (Possibility [2009], 1.4)
     A reaction: His point is that identity is partly determined by the concept or category under which the thing falls. Plausible. Lots of identity muddles seem to come from our conceptual scheme not being quite up to the job when things change.
If one entity is an object, a statue, and some clay, these come apart in at least three ways [Jubien]
     Full Idea: A single entity is a physical object, a piece of clay and a statue. We seem to have that the object could be scattered, but not the other two; the object and the clay could be spherical, but not the statue; and only the object could have different matter.
     From: Michael Jubien (Possibility [2009], 5.2)
     A reaction: His proposal, roughly, is to reduce object-talk to property-talk, and then see the three views of this object as referring to different sets of properties, rather than to a single thing. Promising, except that he goes platonist about properties.
9. Objects / B. Unity of Objects / 3. Unity Problems / d. Coincident objects
The idea of coincident objects is a last resort, as it is opposed to commonsense naturalism [Jubien]
     Full Idea: I find it surprising that some philosophers accept 'coincident objects'. This notion clearly offends against commonsense 'naturalism' about the world, so it should be viewed as a last resort.
     From: Michael Jubien (Possibility [2009], 5.2 n9)
     A reaction: I'm not quite clear why he invokes 'naturalism', but I pass on his intuition because it seems right to me.
9. Objects / C. Structure of Objects / 8. Parts of Objects / a. Parts of objects
Parts seem to matter when it is just an object, but not matter when it is a kind of object [Jubien]
     Full Idea: When thought of just as an object, the parts of a thing seem definitive and their arrangement seems inconsequential. But when thought of as an object of a familiar kind it is reversed: the arrangement is important and the parts are inessential.
     From: Michael Jubien (Possibility [2009], 1.4)
     A reaction: This is analogous to the Ship of Theseus, where we say that the tour operator and the museum keeper give different accounts of whether it is the same ship. The 'kind' Jubien refers to is most likely to be a functional kind.
9. Objects / D. Essence of Objects / 7. Essence and Necessity / b. Essence not necessities
We should not regard essentialism as just nontrivial de re necessity [Jubien]
     Full Idea: I argue against the widely accepted characterization of the doctrine of 'essentialism' as the acceptance of nontrivial de re necessity
     From: Michael Jubien (Possibility [2009], Intro)
     A reaction: I agree entirely. The notion of an essence is powerful if clearly distinguished. The test is: can everything being said about essences be just as easily said by referring to necessities? If so, you are talking about the wrong thing.
9. Objects / E. Objects over Time / 9. Ship of Theseus
Thinking of them as 'ships' the repaired ship is the original, but as 'objects' the reassembly is the original [Jubien]
     Full Idea: Thinking about the original ship as a ship, we think we continue to have the 'same ship' as each part is replaced; ...but when we think of them as physical objects, we think the original ship and the outcome of the reassembly are one and the same.
     From: Michael Jubien (Possibility [2009], 1.4)
     A reaction: It seems to me that you cannot eliminate how we are thinking of the ship as influencing how we should read it. My suggestion is to think of Theseus himself valuing either the repaired or the reassembled version. That's bad for Jubien's account.
Rearranging the planks as a ship is confusing; we'd say it was the same 'object' with a different arrangement [Jubien]
     Full Idea: That the planks are rearranged as a ship elevates the sense of mystery, because arrangements matter for ships, but if they had been arranged differently we would have the same intuition - that it still counts as the same object.
     From: Michael Jubien (Possibility [2009], 1.4)
     A reaction: Implausible. Classic case: can I have my pen back? - smashes it to pieces and hands it over with 'there you are' - that's not my pen! - Jubien says it's the same object! - it isn't my pen, and it isn't the same object either! Where is Shelley's skylark?
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
If two objects are indiscernible across spacetime, how could we decide whether or not they are the same? [Jubien]
     Full Idea: If a bit of matter has a qualitatively indistinguishable object located at a later time, with a path of spacetime connecting them, how could we determine they are identical? Neither identity nor diversity follows from qualitative indiscernibility.
     From: Michael Jubien (Possibility [2009], 1.3)
     A reaction: All these principles expounded by Leibniz were assumed to be timeless, but for identity over time the whole notion of things retaining identity despite changing has to be rethought. Essentialism to the rescue.
10. Modality / A. Necessity / 6. Logical Necessity
Entailment does not result from mutual necessity; mutual necessity ensures entailment [Jubien]
     Full Idea: Typically philosophers say that for P to entail Q is for the proposition that all P's are Q's to be necessary. I think this analysis is backwards, and that necessity rests on entailment, not vice versa.
     From: Michael Jubien (Possibility [2009], 4.4)
     A reaction: His example is that being a horse and being an animal are such that one entails the other. In other words, necessities arise out of property relations (which for Jubien are necessary because the properties are platonically timeless). Wrong.
10. Modality / B. Possibility / 8. Conditionals / f. Pragmatics of conditionals
Sentences with 'if' are only conditionals if they can read as A-implies-B [Enderton]
     Full Idea: Not all sentences using 'if' are conditionals. Consider 'if you want a banana, there is one in the kitchen'. The rough test is that a conditional can be rewritten as 'that A implies that B'.
     From: Herbert B. Enderton (A Mathematical Introduction to Logic (2nd) [2001], 1.6.4)
10. Modality / C. Sources of Modality / 1. Sources of Necessity
Modality concerns relations among platonic properties [Jubien]
     Full Idea: I think modality has to do with relations involving the abstract part of the world, specifically with relations among (Platonic) properties.
     From: Michael Jubien (Possibility [2009], 3.2)
     A reaction: [Sider calls Jubien's the 'governance' view, since abstract relations govern the concrete] I take Jubien here (having done a beautiful demolition job on the possible worlds account of modality) to go spectacularly wrong. Modality starts in the concrete.
To analyse modality, we must give accounts of objects, properties and relations [Jubien]
     Full Idea: The ultimate analysis of possibility and necessity depends on two important ontological decisions: the choice of an analysis of the intuitive concept of a physical object, and the other is the positing of properties and relations.
     From: Michael Jubien (Possibility [2009], Intro)
     A reaction: In the same passage he adopts Quine's view of objects, leading to mereological essentialism, and a Platonic view of properties, based on Lewis's argument for taking some things at face value. One might start with processes and events instead.
10. Modality / E. Possible worlds / 1. Possible Worlds / e. Against possible worlds
The love of possible worlds is part of the dream that technical logic solves philosophical problems [Jubien]
     Full Idea: I believe the contemporary infatuation with possible worlds in philosophy stems in part from a tendency to think that technical logic offers silver-bullet solutions to philosophical problems.
     From: Michael Jubien (Possibility [2009], 3.2)
     A reaction: I would say that the main reason for the infatuation is just novelty. As a technical device it was only invented in the 1960s, so we are in a honeymoon period, as we would be with any new gadget. I can't imagine possible worlds figuring much in 100 years.
Possible worlds don't explain necessity, because they are a bunch of parallel contingencies [Jubien]
     Full Idea: The fundamental problem is that in world theory, what passes for necessity is in effect just a bunch of parallel 'contingencies'.
     From: Michael Jubien (Possibility [2009], 3.2)
     A reaction: Jubien's general complaint is that there is no connection between the possible worlds and the actual world, so they are irrelevant, but this is a nicely different point - that lots of contingent worlds can't add up to necessity. Nice.
17. Mind and Body / E. Mind as Physical / 6. Conceptual Dualism
Analysing mental concepts points to 'inclusionism' - that mental phenomena are part of the physical [Jubien]
     Full Idea: We have (physicalist) 'inclusionism' when the mental is included in the physical, and mental phenomena are to be found among physical phenomena. Only inclusionism is compatible with a genuine physicalist analysis of mental concepts.
     From: Michael Jubien (Possibility [2009], 4.5)
     A reaction: This isn't the thesis of conceptual dualism (which I like), but an interesting accompaniment for it. Jubien is offering this as an alternative to 'reductive' analysis, translating all the mental concepts into physical language. He extends 'physical'.
19. Language / B. Reference / 3. Direct Reference / a. Direct reference
First-order logic tilts in favour of the direct reference theory, in its use of constants for objects [Jubien]
     Full Idea: First-order logic tilts in favor of the direct reference account of proper names by using individual constants to play the intuitive role of names, and by 'interpreting' the constants simply as the individuals that are assigned to them for truth-values.
     From: Michael Jubien (Possibility [2009], Intro)
     A reaction: This is the kind of challenge to orthodoxy that is much needed at the moment. We have an orthodoxy which is almost a new 'scholasticism', that logic will clarify our metaphysics. Trying to enhance the logic for the job may be a dead end.