Combining Texts

All the ideas for 'Material Beings', 'The Pragmatist Account of Truth' and 'Understanding the Infinite'

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79 ideas

2. Reason / B. Laws of Thought / 3. Non-Contradiction
Man has an intense natural interest in the consistency of his own thinking [James]
     Full Idea: After man's interest in breathing freely, the greatest of all his interests (because it never fluctuates or remits….) is his interest in consistency, in feeling that what he now thinks goes with what he thinks on other occasions.
     From: William James (The Pragmatist Account of Truth [1908], 'Seventh')
     A reaction: People notoriously contradict themselves all the time, but I suspect that it is when they get out of their depth in complexities such as politics. They probably achieve great consistency within their own expertise, and in common knowledge.
2. Reason / D. Definition / 12. Paraphrase
We could refer to tables as 'xs that are arranged tablewise' [Inwagen]
     Full Idea: We could paraphrase 'some chairs are heavier than some tables' as 'there are xs that are arranged chairwise and there are ys that are arranged tablewise and the xs are heavier than the ys'.
     From: Peter van Inwagen (Material Beings [1990], 11)
     A reaction: Liggins notes that this involves plural quantification. Being 'arranged tablewise' has become a rather notorious locution in modern ontology. We still have to retain identity, to pick out the xs.
4. Formal Logic / F. Set Theory ST / 1. Set Theory
Second-order set theory just adds a version of Replacement that quantifies over functions [Lavine]
     Full Idea: Second-order set theory is just like first-order set-theory, except that we use the version of Replacement with a universal second-order quantifier over functions from set to sets.
     From: Shaughan Lavine (Understanding the Infinite [1994], VII.4)
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / b. Terminology of ST
An 'upper bound' is the greatest member of a subset; there may be several of these, so there is a 'least' one [Lavine]
     Full Idea: A member m of M is an 'upper bound' of a subset N of M if m is not less than any member of N. A member m of M is a 'least upper bound' of N if m is an upper bound of N such that if l is any other upper bound of N, then m is less than l.
     From: Shaughan Lavine (Understanding the Infinite [1994], III.4)
     A reaction: [if you don't follow that, you'll have to keep rereading it till you do]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / a. Types of set
Collections of things can't be too big, but collections by a rule seem unlimited in size [Lavine]
     Full Idea: Since combinatorial collections are enumerated, some multiplicities may be too large to be gathered into combinatorial collections. But the size of a multiplicity seems quite irrelevant to whether it forms a logical connection.
     From: Shaughan Lavine (Understanding the Infinite [1994], IV.2)
4. Formal Logic / F. Set Theory ST / 3. Types of Set / d. Infinite Sets
Those who reject infinite collections also want to reject the Axiom of Choice [Lavine]
     Full Idea: Many of those who are skeptical about the existence of infinite combinatorial collections would want to doubt or deny the Axiom of Choice.
     From: Shaughan Lavine (Understanding the Infinite [1994], VI.2)
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / g. Axiom of Powers VI
The Power Set is just the collection of functions from one collection to another [Lavine]
     Full Idea: The Power Set is just he codification of the fact that the collection of functions from a mathematical collection to a mathematical collection is itself a mathematical collection that can serve as a domain of mathematical study.
     From: Shaughan Lavine (Understanding the Infinite [1994], VI.1)
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / h. Axiom of Replacement VII
Replacement was immediately accepted, despite having very few implications [Lavine]
     Full Idea: The Axiom of Replacement (of Skolem and Fraenkel) was remarkable for its universal acceptance, though it seemed to have no consequences except for the properties of the higher reaches of the Cantorian infinite.
     From: Shaughan Lavine (Understanding the Infinite [1994], I)
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / i. Axiom of Foundation VIII
Foundation says descending chains are of finite length, blocking circularity, or ungrounded sets [Lavine]
     Full Idea: The Axiom of Foundation (Zermelo 1930) says 'Every (descending) chain in which each element is a member of the previous one is of finite length'. ..This forbids circles of membership, or ungrounded sets. ..The iterative conception gives this centre stage.
     From: Shaughan Lavine (Understanding the Infinite [1994], V.4)
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
Pure collections of things obey Choice, but collections defined by a rule may not [Lavine]
     Full Idea: Combinatorial collections (defined just by the members) obviously obey the Axiom of Choice, while it is at best dubious whether logical connections (defined by a rule) do.
     From: Shaughan Lavine (Understanding the Infinite [1994], IV.2)
The controversy was not about the Axiom of Choice, but about functions as arbitrary, or given by rules [Lavine]
     Full Idea: The controversy was not about Choice per se, but about the correct notion of function - between advocates of taking mathematics to be about arbitrary functions and advocates of taking it to be about functions given by rules.
     From: Shaughan Lavine (Understanding the Infinite [1994], I)
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / c. Logical sets
The 'logical' notion of class has some kind of definition or rule to characterise the class [Lavine]
     Full Idea: The Peano-Russell notion of class is the 'logical' notion, where each collection is associated with some kind of definition or rule that characterises the members of the collection.
     From: Shaughan Lavine (Understanding the Infinite [1994], IV.1)
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / e. Iterative sets
The iterative conception of set wasn't suggested until 1947 [Lavine]
     Full Idea: The iterative conception of set was not so much as suggested, let alone advocated by anyone, until 1947.
     From: Shaughan Lavine (Understanding the Infinite [1994], I)
The iterative conception needs the Axiom of Infinity, to show how far we can iterate [Lavine]
     Full Idea: The iterative conception of sets does not tell us how far to iterate, and so we must start with an Axiom of Infinity. It also presupposes the notion of 'transfinite iteration'.
     From: Shaughan Lavine (Understanding the Infinite [1994], V.5)
The iterative conception doesn't unify the axioms, and has had little impact on mathematical proofs [Lavine]
     Full Idea: The iterative conception does not provide a conception that unifies the axioms of set theory, ...and it has had very little impact on what theorems can be proved.
     From: Shaughan Lavine (Understanding the Infinite [1994], V.5)
     A reaction: He says he would like to reject the iterative conception, but it may turn out that Foundation enables new proofs in mathematics (though it hasn't so far).
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / f. Limitation of Size
Limitation of Size: if it's the same size as a set, it's a set; it uses Replacement [Lavine]
     Full Idea: Limitation of Size has it that if a collection is the same size as a set, then it is a set. The Axiom of Replacement is characteristic of limitation of size.
     From: Shaughan Lavine (Understanding the Infinite [1994], V.5)
4. Formal Logic / F. Set Theory ST / 6. Ordering in Sets
A collection is 'well-ordered' if there is a least element, and all of its successors can be identified [Lavine]
     Full Idea: A collection M is 'well-ordered' by a relation < if < linearly orders M with a least element, and every subset of M that has an upper bound not in it has an immediate successor.
     From: Shaughan Lavine (Understanding the Infinite [1994], III.4)
4. Formal Logic / G. Formal Mereology / 1. Mereology
Mereology is 'nihilistic' (just atoms) or 'universal' (no restrictions on what is 'whole') [Inwagen, by Varzi]
     Full Idea: Van Ingwagen writes of 'mereological nihilism' (that only mereological atoms exist) and of 'mereological universalism' (adhering to the principle of Unrestricted Composition).
     From: report of Peter van Inwagen (Material Beings [1990], p.72-) by Achille Varzi - Mereology 4.3
     A reaction: They both look mereologically nihilistic to me, in comparison with an account that builds on 'natural' wholes and their parts. You can only be 'unrestricted' if you view the 'wholes' in your vast ontology as pretty meaningless (as Lewis does, Idea 10660).
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Second-order logic presupposes a set of relations already fixed by the first-order domain [Lavine]
     Full Idea: The distinctive feature of second-order logic is that it presupposes that, given a domain, there is a fact of the matter about what the relations on it are, so that the range of the second-order quantifiers is fixed as soon as the domain is fixed.
     From: Shaughan Lavine (Understanding the Infinite [1994], V.3)
     A reaction: This sounds like a rather large assumption, which is open to challenge. I am not sure whether it was the basis of Quine's challenge to second-order logic. He seems to have disliked its vagueness, because it didn't stick with 'objects'.
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
The 'Law' of Excluded Middle needs all propositions to be definitely true or definitely false [Inwagen]
     Full Idea: I think the validity of the 'Law' of Excluded Middle depends on the assumption that every proposition is definitely true or definitely false.
     From: Peter van Inwagen (Material Beings [1990], 18)
     A reaction: I think this is confused. He cites vagueness as the problem, but that is a problem for Bivalence. If excluded middle is read as 'true or not-true', that leaves the meaning of 'not-true' open, and never mentions the bivalent 'false'.
Mathematical proof by contradiction needs the law of excluded middle [Lavine]
     Full Idea: The Law of Excluded Middle is (part of) the foundation of the mathematical practice of employing proofs by contradiction.
     From: Shaughan Lavine (Understanding the Infinite [1994], VI.1)
     A reaction: This applies in a lot of logic, as well as in mathematics. Come to think of it, it applies in Sudoku.
5. Theory of Logic / E. Structures of Logic / 4. Variables in Logic
Variables are just like pronouns; syntactic explanations get muddled over dummy letters [Inwagen]
     Full Idea: Explanations in terms of syntax do not satisfactorily distinguish true variables from dummy or schematic letters. Identifying variables with pronouns, however, provides a genuine explanation of what variables are.
     From: Peter van Inwagen (Material Beings [1990], 02)
     A reaction: I like this because it shows that our ordinary thought and speech use variables all the time ('I've forgotten something - what was it?'). He says syntax is fine for maths, but not for ordinary understanding.
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / b. The Heap paradox ('Sorites')
There are no heaps [Inwagen]
     Full Idea: Fortunately ....there are no heaps.
     From: Peter van Inwagen (Material Beings [1990], 18)
     A reaction: This is the nihilist view of (inorganic) physical objects. If a wild view solves all sorts of problems, one should take it serious. It is why I take reductive physicalism about the mind seriously. (Well, it's true, actually)
6. Mathematics / A. Nature of Mathematics / 1. Mathematics
Mathematics is nowadays (thanks to set theory) regarded as the study of structure, not of quantity [Lavine]
     Full Idea: Mathematics is today thought of as the study of abstract structure, not the study of quantity. That point of view arose directly out of the development of the set-theoretic notion of abstract structure.
     From: Shaughan Lavine (Understanding the Infinite [1994], III.2)
     A reaction: It sounds as if Structuralism, which is a controversial view in philosophy, is a fait accompli among mathematicians.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
Every rational number, unlike every natural number, is divisible by some other number [Lavine]
     Full Idea: One reason to introduce the rational numbers is that it simplifes the theory of division, since every rational number is divisible by every nonzero rational number, while the analogous statement is false for the natural numbers.
     From: Shaughan Lavine (Understanding the Infinite [1994], VI.3)
     A reaction: That is, with rations every division operation has an answer.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
For the real numbers to form a set, we need the Continuum Hypothesis to be true [Lavine]
     Full Idea: The chief importance of the Continuum Hypothesis for Cantor (I believe) was that it would show that the real numbers form a set, and hence that they were encompassed by his theory.
     From: Shaughan Lavine (Understanding the Infinite [1994], IV.2)
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / h. Reals from Cauchy
Cauchy gave a necessary condition for the convergence of a sequence [Lavine]
     Full Idea: The Cauchy convergence criterion for a sequence: the sequence S0,S1,... has a limit if |S(n+r) - S(n)| is less than any given quantity for every value of r and sufficiently large values of n. He proved this necessary, but not sufficient.
     From: Shaughan Lavine (Understanding the Infinite [1994], 2.5)
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / i. Reals from cuts
The two sides of the Cut are, roughly, the bounding commensurable ratios [Lavine]
     Full Idea: Roughly speaking, the upper and lower parts of the Dedekind cut correspond to the commensurable ratios greater than and less than a given incommensurable ratio.
     From: Shaughan Lavine (Understanding the Infinite [1994], II.6)
     A reaction: Thus there is the problem of whether the contents of the gap are one unique thing, or many.
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / c. Counting procedure
Counting results in well-ordering, and well-ordering makes counting possible [Lavine]
     Full Idea: Counting a set produces a well-ordering of it. Conversely, if one has a well-ordering of a set, one can count it by following the well-ordering.
     From: Shaughan Lavine (Understanding the Infinite [1994], III.4)
     A reaction: Cantor didn't mean that you could literally count the set, only in principle.
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
The theory of infinity must rest on our inability to distinguish between very large sizes [Lavine]
     Full Idea: The indiscernibility of indefinitely large sizes will be a critical part of the theory of indefinitely large sizes.
     From: Shaughan Lavine (Understanding the Infinite [1994], VIII.2)
The infinite is extrapolation from the experience of indefinitely large size [Lavine]
     Full Idea: My proposal is that the concept of the infinite began with an extrapolation from the experience of indefinitely large size.
     From: Shaughan Lavine (Understanding the Infinite [1994], VIII.2)
     A reaction: I think it might be better to talk of an 'abstraction' than an 'extrapolition', since the latter is just more of the same, which doesn't get you to concept. Lavine spends 100 pages working out his proposal.
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / c. Potential infinite
The intuitionist endorses only the potential infinite [Lavine]
     Full Idea: The intuitionist endorse the actual finite, but only the potential infinite.
     From: Shaughan Lavine (Understanding the Infinite [1994], VI.2)
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / f. Uncountable infinities
'Aleph-0' is cardinality of the naturals, 'aleph-1' the next cardinal, 'aleph-ω' the ω-th cardinal [Lavine]
     Full Idea: The symbol 'aleph-nought' denotes the cardinal number of the set of natural numbers. The symbol 'aleph-one' denotes the next larger cardinal number. 'Aleph-omega' denotes the omega-th cardinal number.
     From: Shaughan Lavine (Understanding the Infinite [1994], III.3)
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / h. Ordinal infinity
Ordinals are basic to Cantor's transfinite, to count the sets [Lavine]
     Full Idea: The ordinals are basic because the transfinite sets are those that can be counted, or (equivalently for Cantor), those that can be numbered by an ordinal or are well-ordered.
     From: Shaughan Lavine (Understanding the Infinite [1994], III.4)
     A reaction: Lavine observes (p.55) that for Cantor 'countable' meant 'countable by God'!
Paradox: the class of all ordinals is well-ordered, so must have an ordinal as type - giving a bigger ordinal [Lavine]
     Full Idea: The paradox of the largest ordinal (the 'Burali-Forti') is that the class of all ordinal numbers is apparently well-ordered, and so it has an ordinal number as order type, which must be the largest ordinal - but all ordinals can be increased by one.
     From: Shaughan Lavine (Understanding the Infinite [1994], III.5)
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / i. Cardinal infinity
Paradox: there is no largest cardinal, but the class of everything seems to be the largest [Lavine]
     Full Idea: The paradox of the largest cardinal ('Cantor's Paradox') says the diagonal argument shows there is no largest cardinal, but the class of all individuals (including the classes) must be the largest cardinal number.
     From: Shaughan Lavine (Understanding the Infinite [1994], III.5)
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Set theory will found all of mathematics - except for the notion of proof [Lavine]
     Full Idea: Every theorem of mathematics has a counterpart with set theory - ...but that theory cannot serve as a basis for the notion of proof.
     From: Shaughan Lavine (Understanding the Infinite [1994], V.3)
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / b. Against mathematical platonism
Modern mathematics works up to isomorphism, and doesn't care what things 'really are' [Lavine]
     Full Idea: In modern mathematics virtually all work is only up to isomorphism and no one cares what the numbers or points and lines 'really are'.
     From: Shaughan Lavine (Understanding the Infinite [1994], VI.1)
     A reaction: At least that leaves the field open for philosophers, because we do care what things really are. So should everybody else, but there is no persuading some people.
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / b. Intuitionism
Intuitionism rejects set-theory to found mathematics [Lavine]
     Full Idea: Intuitionism in philosophy of mathematics rejects set-theoretic foundations.
     From: Shaughan Lavine (Understanding the Infinite [1994], V.3 n33)
7. Existence / C. Structure of Existence / 8. Stuff / a. Pure stuff
I reject talk of 'stuff', and treat it in terms of particles [Inwagen]
     Full Idea: I have a great deal of difficulty with an ontology that includes 'stuffs' in addition to things. ...I prefer to replace talk of sameness of matter with talk of sameness of particles.
     From: Peter van Inwagen (Material Beings [1990], 14)
     A reaction: Van Inwagen is wedded to the idea that reality is composed of 'simples' - even if physicists seem now to talk of 'fields' as much as they do about objects in the fields. Has philosophy yet caught up with Maxwell?
7. Existence / D. Theories of Reality / 8. Facts / c. Facts and truths
Realities just are, and beliefs are true of them [James]
     Full Idea: Realities are not true, they are; and beliefs are true of them.
     From: William James (The Pragmatist Account of Truth [1908], 'Fourth')
     A reaction: At last, a remark by James about truth which I really like. For 'realities' I would use the word 'facts'.
7. Existence / D. Theories of Reality / 10. Vagueness / d. Vagueness as linguistic
Singular terms can be vague, because they can contain predicates, which can be vague [Inwagen]
     Full Idea: Since singular terms can contain predicates, and since vague predicates are common, vague singular terms are common. For 'the tallest man that Sally knows' there are lots of men for whom it is unclear whether Sally knows them.
     From: Peter van Inwagen (Material Beings [1990], 17)
9. Objects / A. Existence of Objects / 1. Physical Objects
Material objects are in space and time, move, have a surface and mass, and are made of some stuff [Inwagen]
     Full Idea: A thing is a material object if it occupies space and endures through time and can move about in space (literally move, unlike a shadow or wave or reflection) and has a surface and has a mass and is made of a certain stuff or stuffs.
     From: Peter van Inwagen (Material Beings [1990], 01)
     A reaction: It is not at all clear what electrons (which must count for him as 'simples') are made of.
Maybe table-shaped particles exist, but not tables [Inwagen, by Lowe]
     Full Idea: Van Ingwagen holds that although table-shaped collections of particles exist, tables do not.
     From: report of Peter van Inwagen (Material Beings [1990], Ch.13) by E.J. Lowe - The Possibility of Metaphysics 2.3
     A reaction: I find this idea appealing. See the ideas of Trenton Merricks. When you get down to micro-level, it is hard to individuate a table among the force fields, and hard to distinguish a table from a smashed or burnt table. An ontology without objects?
9. Objects / A. Existence of Objects / 6. Nihilism about Objects
Nihilism says composition between single things is impossible [Inwagen]
     Full Idea: Nihilism about objects says there is a Y such that the Xs compose it if and only if there is only one of the Xs.
     From: Peter van Inwagen (Material Beings [1990], 08)
     A reaction: He says that Unger, the best known 'nihilist' about objects, believes a different version - claiming there are composites, but they never make up the ordinary objects we talk about.
If there are no tables, but tables are things arranged tablewise, the denial of tables is a contradiction [Liggins on Inwagen]
     Full Idea: Van Inwagen says 'there are no tables', and 'there are tables' means 'there are some things arranged tablewise'. Presumably 'there are no tables' negates the latter claim, saying no things are arranged tablewise. But he should think that is false.
     From: comment on Peter van Inwagen (Material Beings [1990], 10) by David Liggins - Nihilism without Self-Contradiction 3
     A reaction: Liggins's nice paper shows that Van Inwagen is in a potential state of contradiction when he starts saying that there are no tables, but that there are things arranged tablewise, and that they amount to tables. Liggins offers him an escape.
Actions by artefacts and natural bodies are disguised cooperations, so we don't need them [Inwagen]
     Full Idea: All the activities apparently carried out by shelves and stars and other artefacts and natural bodies can be understood as disguised cooperative activities. And, therefore, we are not forced to grant existence to any artefacts or natural bodies.
     From: Peter van Inwagen (Material Beings [1990], 12)
     A reaction: In 'the crowd tore her to pieces' are we forced to accept the existence of a crowd? We can't say 'Jack tore her to pieces' and 'Jill tore her to pieces'. If a plural quantification is unavoidable, we have to accept the plurality. Perhaps.
9. Objects / B. Unity of Objects / 1. Unifying an Object / b. Unifying aggregates
Every physical thing is either a living organism or a simple [Inwagen]
     Full Idea: The thesis about composition and parthood that I am advocating has far-reaching ontological consequences: that every physical thing is either a living organism or a simple.
     From: Peter van Inwagen (Material Beings [1990], 10)
     A reaction: A 'simple' is a placeholder for anything considered to be a fundamental unit of existence (such as an electron or a quark). This amazingly sharp distinction strikes me as utterly implausible. There is too much in the middle ground.
9. Objects / B. Unity of Objects / 3. Unity Problems / c. Statue and clay
The statue and lump seem to share parts, but the statue is not part of the lump [Inwagen]
     Full Idea: Those who believe that the statue is distinct from the lump should concede that whatever shares a part with the statue shares a part with the lump but deny that the statue is a part of the lump.
     From: Peter van Inwagen (Material Beings [1990], 05)
     A reaction: Standard mereology says if they share all their parts then they are the same thing, so it is hard to explain how they are 'distinct'. The distinction is only modal - that they could be separated (by squashing, or by part substitution).
If you knead clay you make an infinite series of objects, but they are rearrangements, not creations [Inwagen]
     Full Idea: If you can make a (random) gollyswoggle by accident by kneading clay, then you must be causing the generation and corruption of a series of objects of infinitesimal duration. ...We have not augmented the furniture of the world but only rearranged it.
     From: Peter van Inwagen (Material Beings [1990], 13)
     A reaction: Van Inwagen's final conclusion is a bit crazy, but I am in sympathy with his general scepticism about what sorts of things definitively constitute 'objects'. He overrates simples, and he overrates lives.
9. Objects / C. Structure of Objects / 3. Matter of an Object
I assume matter is particulate, made up of 'simples' [Inwagen]
     Full Idea: I assume in this book that matter is ultimately particulate. Every material being is composed of things that have no proper parts: 'elementary particles' or 'mereological atoms' or 'metaphysical simples'.
     From: Peter van Inwagen (Material Beings [1990], Pref)
     A reaction: It may be that modern physics doesn't support this, if 'fields' is the best term for what is fundamental. Best to treat his book as hypothetical - IF there are just simples, proceed as follows.
9. Objects / C. Structure of Objects / 5. Composition of an Object
If contact causes composition, do two colliding balls briefly make one object? [Inwagen]
     Full Idea: If composition just requires contact, if I cause the cue ball to rebound from the eight ball, do I thereby create a short-lived object shaped like two slightly flattened spheres in contact?
     From: Peter van Inwagen (Material Beings [1990], 03)
     A reaction: [compressed]
If bricks compose a house, that is at least one thing, but it might be many things [Inwagen]
     Full Idea: If composition just requires contact, that tells us that the bricks of a house compose at least one thing; it does not tell us that they also compose at most one thing.
     From: Peter van Inwagen (Material Beings [1990], 04)
9. Objects / C. Structure of Objects / 8. Parts of Objects / a. Parts of objects
I think parthood involves causation, and not just a reasonably stable spatial relationship [Inwagen]
     Full Idea: I propose that parthood essentially involves causation. Too many philosophers have supposed that objects compose something when and only when they stand in some (more or less stable) spatial relationship to one another.
     From: Peter van Inwagen (Material Beings [1990], 09)
     A reaction: I have to say that I like this, even though it comes from a thinker who is close to nihilism about ordinary non-living objects. He goes on to say that only a 'life' provides the right sort of causal relationship.
We can deny whole objects but accept parts, by referring to them as plurals within things [Inwagen, by Liggins]
     Full Idea: Van Inwagen's claim that nothing has parts causes incredulity. ..But the problem is not with endorsing the sentence 'Some things have parts'; it is with interpreting this sentence by means of singular resources rather than plural ones.
     From: report of Peter van Inwagen (Material Beings [1990], 7) by David Liggins - Nihilism without Self-Contradiction
     A reaction: Van Inwagen notoriously denies the existence of normal physical objects. Liggins shows that modern formal plural quantification gives a better way of presenting his theory, by accepting tables and parts of tables as plurals of basic entities.
9. Objects / C. Structure of Objects / 8. Parts of Objects / c. Wholes from parts
Special Composition Question: when is a thing part of something? [Inwagen]
     Full Idea: The Special Composition Question asks, In what circumstances is a thing a (proper) part of something?
     From: Peter van Inwagen (Material Beings [1990], 02)
     A reaction: [He qualifies this formulation as 'misleading'] It's a really nice basic question for the metaphysics of objects.
9. Objects / D. Essence of Objects / 8. Essence as Explanatory
The essence of a star includes the released binding energy which keeps it from collapse [Inwagen]
     Full Idea: I think it is part of the essence of a star that the radiation pressures that oppose the star's tendency to gravitational collapse has its source in the release of no-longer-needed nuclear binding energy when colliding nuclei fuse in the star's hot core.
     From: Peter van Inwagen (Material Beings [1990], 07)
     A reaction: A perfect example of giving the essence of something as the bottom level of its explanation. This even comes from someone who doesn't really believe in stars!
9. Objects / D. Essence of Objects / 11. Essence of Artefacts
The persistence of artifacts always covertly involves intelligent beings [Inwagen]
     Full Idea: Statements that are apparently about the persistence of artifacts make covert reference to the dispositions of intelligent beings to maintain certain arrangements of matter.
     From: Peter van Inwagen (Material Beings [1990], 13)
     A reaction: If you build a self-sustaining windmill that pumps water, that seems to have an identity of its own, apart from the intentions of whoever makes it and repairs it. The function of an artefact is not just the function we want it to have.
9. Objects / E. Objects over Time / 7. Intermittent Objects
When an electron 'leaps' to another orbit, is the new one the same electron? [Inwagen]
     Full Idea: Is the 'new' electron in the lower orbit the one that was in the higher orbit? Physics, as far as I can tell, has nothing to say about this.
     From: Peter van Inwagen (Material Beings [1990], 14)
     A reaction: I suspect that physicists would say that philosophers are worrying about such questions because they haven't grasped the new conceptual scheme that emerged in 1926. The poor mutts insist on hanging on to 'objects'.
9. Objects / E. Objects over Time / 9. Ship of Theseus
If you reject transitivity of vague identity, there is no Ship of Theseus problem [Inwagen]
     Full Idea: If you have rejected the Principle of the Transitivity of (vague) Identity, it is hard to see how the problem of the Ship of Theseus could arise.
     From: Peter van Inwagen (Material Beings [1990], 18)
     A reaction: I think this may well be the best solution to the whole problem
9. Objects / F. Identity among Objects / 1. Concept of Identity
We should talk of the transitivity of 'identity', and of 'definite identity' [Inwagen]
     Full Idea: In some contexts, the principle of 'the transitivity of identity' should be called 'the transitivity of definite identity'.
     From: Peter van Inwagen (Material Beings [1990], 18)
     A reaction: He is making room for a person to retain identity despite having changed. Applause from me.
10. Modality / C. Sources of Modality / 5. Modality from Actuality
Actuality proves possibility, but that doesn't explain how it is possible [Inwagen]
     Full Idea: A proof of actuality is a proof of possibility, but that does not invariably explain the possibility whose existence it demonstrates, for we may know that a certain thing is actual (and hence possible) but have no explanation of how it could be possible.
     From: Peter van Inwagen (Material Beings [1990], 12)
     A reaction: I like this, because my project is to see all of philosophy in terms of explanation rather than of description.
10. Modality / E. Possible worlds / 3. Transworld Objects / c. Counterparts
Counterparts reduce counterfactual identity to problems about similarity relations [Inwagen]
     Full Idea: Counterpart Theory essentially reduces all problems about counterfactual identity to problems about choosing appropriate similarity relations. That is, Counterpart Theory essentially eliminates problems of counterfactual identity as such.
     From: Peter van Inwagen (Material Beings [1990], 14)
10. Modality / E. Possible worlds / 3. Transworld Objects / e. Possible Objects
A merely possible object clearly isn't there, so that is a defective notion [Inwagen]
     Full Idea: The notion of a merely possible object is an even more defective notion than the notion of a borderline object; after all, a merely possible object is an object that definitely isn't there.
     From: Peter van Inwagen (Material Beings [1990], 19)
Merely possible objects must be consistent properties, or haecceities [Inwagen]
     Full Idea: Talk of merely possible objects may be redeemed in either maximally consistent sets of properties or in haecceities.
     From: Peter van Inwagen (Material Beings [1990], 19)
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / b. Pro-coherentism
We find satisfaction in consistency of all of our beliefs, perceptions and mental connections [James]
     Full Idea: We find satisfaction in consistency between the present idea and the entire rest of our mental equipment, including the whole order of our sensations, and that of our intuitions of likeness and difference, and our whole stock previously acquired truths.
     From: William James (The Pragmatist Account of Truth [1908], 'Fourth')
     A reaction: I like this, apart from the idea that the criterion of good coherence seems to be subjective 'satisfaction'. We should ask why some large set of beliefs is coherent. I assume nature is coherent, and truth is the best explanation of our coherence about it.
27. Natural Reality / B. Modern Physics / 3. Chromodynamics / a. Chromodynamics
The strong force pulls, but also pushes apart if nucleons get too close together [Inwagen]
     Full Idea: The strong force doesn't always pull nucleons together, but pushes them apart if they get too close.
     From: Peter van Inwagen (Material Beings [1990], 07)
     A reaction: Philosophers tend to learn their physics from other philosophers. But that's because philosophers are brilliant at picking out the interesting parts of physics, and skipping the boring stuff.
27. Natural Reality / F. Chemistry / 2. Modern Elements
Is one atom a piece of gold, or is a sizable group of atoms required? [Inwagen]
     Full Idea: A physicist once told me that of course a gold atom was a piece of gold, and a physical chemist has assured me that the smallest possible piece of gold would have to be composed of sixteen or seventeen atoms.
     From: Peter van Inwagen (Material Beings [1990], 01)
     A reaction: The issue is at what point all the properties that we normally begin to associate with gold begin to appear. One water molecule can hardly have a degree of viscosity or liquidity.
27. Natural Reality / G. Biology / 2. Life
At the lower level, life trails off into mere molecular interaction [Inwagen]
     Full Idea: The lives of the lower links of the Great Chain of Being trail off into vague, temporary episodes of molecular interaction.
     From: Peter van Inwagen (Material Beings [1990], 18)
     A reaction: His case involves conceding all sorts of vagueness to life, but asserting the utter distinctness of the full blown cases of more elaborate life. I don't really concede the distinction.
A tumour may spread a sort of life, but it is not a life, or an organism [Inwagen]
     Full Idea: A tumour is not an organism (or a parasite) and there is no self-regulating event that is its life. It does not fill one space, but is a locus within which a certain sort of thing is happening: the spreading of a certain sort of (mass-term) life.
     From: Peter van Inwagen (Material Beings [1990], 09)
Being part of an organism's life is a matter of degree, and vague [Inwagen]
     Full Idea: Being caught up in the life of an organism is, like being rich or being tall, a matter of degree, and is in that sense a vague condition.
     From: Peter van Inwagen (Material Beings [1990], 17)
     A reaction: Van Inwagen is trying to cover himself, given that he makes a sharp distinction between living organisms, which are unified objects, and everything else, which isn't. There may be a vague centre to a 'life', as well as vague boundaries.
Some events are only borderline cases of lives [Inwagen]
     Full Idea: There are events of which it is neither definitely true nor definitely false that those events are lives. I do not see how we can deny this.
     From: Peter van Inwagen (Material Beings [1990], 18)
     A reaction: Very frustrating, since this is my main objection to Van Inwagen's distinction between unified lives and mere collections of simples. Some boundaries are real enough, despite their vagueness, and others indicate that there is no real distinction.
Unlike waves, lives are 'jealous'; it is almost impossible for them to overlap [Inwagen]
     Full Idea: A wave is not a 'jealous' event. Lives, however, are jealous. It cannot be that the activities of the Xs constitute at one and the same time two lives. Only in certain special cases can two lives overlap.
     From: Peter van Inwagen (Material Beings [1990], 09)
One's mental and other life is centred on the brain, unlike any other part of the body [Inwagen]
     Full Idea: One's life - not simply one's mental life - is centered in the activity of the simples that virtually compose one's brain in a way in which it is not centered in the activity of any of the other simples that compose one.
     From: Peter van Inwagen (Material Beings [1990], 15)
     A reaction: This justifies the common view that 'one follows one's brain'. I take that to mean that my brain embodies my essence. I would read 'centered on' as 'explains'.
The chemical reactions in a human life involve about sixteen elements [Inwagen]
     Full Idea: There are sixteen or so chemical elements involved in those chemical reactions that collectively constitute the life of a human being.
     From: Peter van Inwagen (Material Beings [1990], 09)
Life is vague at both ends, but could it be totally vague? [Inwagen]
     Full Idea: Individual human lives are infected with vagueness at both ends. ...But could there be a 'borderline life'?
     From: Peter van Inwagen (Material Beings [1990], 18)
     A reaction: Van Inwagen says (p.239) that there may be wholly vague lives, though it would suit his case better if there were not.
A flame is like a life, but not nearly so well individuated [Inwagen]
     Full Idea: A flame, though it is a self-maintaining event, does not seem to be nearly so well individuated as a life.
     From: Peter van Inwagen (Material Beings [1990], 09)
     A reaction: This is to counter the standard problem that if you attempt to define 'life', fire turns out to tick nearly all the same boxes. The concept of 'individuated' often strikes me as unsatisfactory. How does a bonfire fail to be individuated?
If God were to 'reassemble' my atoms of ten years ago, the result would certainly not be me [Inwagen]
     Full Idea: If God were to 'reassemble' the atoms that composed me ten years ago, the resulting organism would certainly not be me.
     From: Peter van Inwagen (Material Beings [1990], 13)
     A reaction: What is obvious to Van Inwagen is not obvious to me. He thinks lives are special. Such examples just leave us bewildered about what counts as 'the same', because our concept of sameness wasn't designed to deal with such cases.
28. God / B. Proving God / 2. Proofs of Reason / b. Ontological Proof critique
There is no reason to think that mere existence is a valuable thing [Inwagen]
     Full Idea: There is no reason to suppose - whatever Saint Anselm and Descartes may have thought - that mere existence is a valuable thing.
     From: Peter van Inwagen (Material Beings [1990], 12)
     A reaction: This is one of the simplest and most powerful objections to the Ontological Argument. God's existence may be of great value, but the existence of Hitler wasn't.