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All the ideas for 'Natural Kinds', 'Notes on Logic' and 'A Structural Account of Mathematics'

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37 ideas

1. Philosophy / G. Scientific Philosophy / 3. Scientism
Philosophy is continuous with science, and has no external vantage point [Quine]
     Full Idea: I see philosophy not as an a priori propaedeutic or groundwork for science, but as continuous with science. I see philosophy and science as in the same boat. …There is no external vantage point, no first philosophy.
     From: Willard Quine (Natural Kinds [1969], p.126)
     A reaction: Philosophy is generalisation. Science holds the upper hand, because it settles the subject-matter to be generalised.
4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
We only know relational facts about the empty set, but nothing intrinsic [Chihara]
     Full Idea: Everything we know about the empty set is relational; we know that nothing is the membership relation to it. But what do we know about its 'intrinsic properties'?
     From: Charles Chihara (A Structural Account of Mathematics [2004], 01.5)
     A reaction: Set theory seems to depend on the concept of the empty set. Modern theorists seem over-influenced by the Quine-Putnam view, that if science needs it, we must commit ourselves to its existence.
In simple type theory there is a hierarchy of null sets [Chihara]
     Full Idea: In simple type theory, there is a null set of type 1, a null set of type 2, a null set of type 3..... (Quine has expressed his distaste for this).
     From: Charles Chihara (A Structural Account of Mathematics [2004], 07.4)
     A reaction: It is bad enough trying to individuate the unique null set, without whole gangs of them drifting indistinguishably through the logical fog. All rational beings should share Quine's distaste, even if Quine is wrong.
Realists about sets say there exists a null set in the real world, with no members [Chihara]
     Full Idea: In the Gödelian realistic view of set theory the statement that there is a null set as the assertion of the existence in the real world of a set that has no members.
     From: Charles Chihara (A Structural Account of Mathematics [2004], 11.6)
     A reaction: It seems to me obvious that such a claim is nonsense on stilts. 'In the beginning there was the null set'?
The null set is a structural position which has no other position in membership relation [Chihara]
     Full Idea: In the structuralist view of sets, in structures of a certain sort the null set is taken to be a position (or point) that will be such that no other position (or point) will be in the membership relation to it.
     From: Charles Chihara (A Structural Account of Mathematics [2004], 11.6)
     A reaction: It would be hard to conceive of something having a place in a structure if nothing had a relation to it, so is the null set related to singeton sets but not there members. It will be hard to avoid Platonism here. Set theory needs the null set.
4. Formal Logic / F. Set Theory ST / 3. Types of Set / c. Unit (Singleton) Sets
What is special about Bill Clinton's unit set, in comparison with all the others? [Chihara]
     Full Idea: What is it about the intrinsic properties of just that one unit set in virtue of which Bill Clinton is related to just it and not to any other unit sets in the set-theoretical universe?
     From: Charles Chihara (A Structural Account of Mathematics [2004], 01.5)
     A reaction: If we all kept pet woodlice, we had better not hold a wood louse rally, or we might go home with the wrong one. My singleton seems seems remarkably like yours. Could we, perhaps, swap, just for a change?
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / a. Sets as existing
The set theorist cannot tell us what 'membership' is [Chihara]
     Full Idea: The set theorist cannot tell us anything about the true relationship of membership.
     From: Charles Chihara (A Structural Account of Mathematics [2004], 01.5)
     A reaction: If three unrelated objects suddenly became members of a set, it is hard to see how the world would have changed, except in the minds of those thinking about it.
4. Formal Logic / F. Set Theory ST / 7. Natural Sets
ZFU refers to the physical world, when it talks of 'urelements' [Chihara]
     Full Idea: ZFU set theory talks about physical objects (the urelements), and hence is in some way about the physical world.
     From: Charles Chihara (A Structural Account of Mathematics [2004], 11.5)
     A reaction: This sounds a bit surprising, given that the whole theory would appear to be quite unaffected if God announced that idealism is true and there are no physical objects.
4. Formal Logic / F. Set Theory ST / 8. Critique of Set Theory
A pack of wolves doesn't cease when one member dies [Chihara]
     Full Idea: A pack of wolves is not thought to go out of existence just because some member of the pack is killed.
     From: Charles Chihara (A Structural Account of Mathematics [2004], 07.5)
     A reaction: The point is that the formal extensional notion of a set doesn't correspond to our common sense notion of a group or class. Even a highly scientific theory about wolves needs a loose notion of a wolf pack.
5. Theory of Logic / E. Structures of Logic / 6. Relations in Logic
The mathematics of relations is entirely covered by ordered pairs [Chihara]
     Full Idea: Everything one needs to do with relations in mathematics can be done by taking a relation to be a set of ordered pairs. (Ordered triples etc. can be defined as order pairs, so that <x,y,z> is <x,<y,z>>).
     From: Charles Chihara (A Structural Account of Mathematics [2004], 07.2)
     A reaction: How do we distinguish 'I own my cat' from 'I love my cat'? Or 'I quite like my cat' from 'I adore my cat'? Nevertheless, this is an interesting starting point for a discussion of relations.
5. Theory of Logic / K. Features of Logics / 2. Consistency
Sentences are consistent if they can all be true; for Frege it is that no contradiction can be deduced [Chihara]
     Full Idea: In first-order logic a set of sentences is 'consistent' iff there is an interpretation (or structure) in which the set of sentences is true. ..For Frege, though, a set of sentences is consistent if it is not possible to deduce a contradiction from it.
     From: Charles Chihara (A Structural Account of Mathematics [2004], 02.1)
     A reaction: The first approach seems positive, the second negative. Frege seems to have a higher standard, which is appealing, but the first one seems intuitively right. There is a possible world where this could work.
6. Mathematics / A. Nature of Mathematics / 2. Geometry
Klein summarised geometry as grouped together by transformations [Quine]
     Full Idea: Felix Klein's so-called 'Erlangerprogramm' in geometry involved characterizing the various branches of geometry by what transformations were irrelevant to each.
     From: Willard Quine (Natural Kinds [1969], p.137)
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
Analytic geometry gave space a mathematical structure, which could then have axioms [Chihara]
     Full Idea: With the invention of analytic geometry (by Fermat and then Descartes) physical space could be represented as having a mathematical structure, which could eventually lead to its axiomatization (by Hilbert).
     From: Charles Chihara (A Structural Account of Mathematics [2004], 02.3)
     A reaction: The idea that space might have axioms seems to be pythagoreanism run riot. I wonder if there is some flaw at the heart of Einstein's General Theory because of this?
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / c. Nominalist structuralism
We can replace existence of sets with possibility of constructing token sentences [Chihara, by MacBride]
     Full Idea: Chihara's 'constructability theory' is nominalist - mathematics is reducible to a simple theory of types. Instead of talk of sets {x:x is F}, we talk of open sentences Fx defining them. Existence claims become constructability of sentence tokens.
     From: report of Charles Chihara (A Structural Account of Mathematics [2004]) by Fraser MacBride - Review of Chihara's 'Structural Acc of Maths' p.81
     A reaction: This seems to be approaching the problem in a Fregean way, by giving an account of the semantics. Chihara is trying to evade the Quinean idea that assertion is ontological commitment. But has Chihara retreated too far? How does he assert existence?
7. Existence / C. Structure of Existence / 8. Stuff / a. Pure stuff
Mass terms just concern spread, but other terms involve both spread and individuation [Quine]
     Full Idea: 'Yellow' and 'water' are mass terms, concerned only with spread; 'apple' and 'square' are terms of divided reference, concerned with both spread and individuation.
     From: Willard Quine (Natural Kinds [1969], p.124)
     A reaction: Would you like some apple? Pass me that water. It is helpful to see that it is a requirement of 'individuation' that is missing from terms for stuff.
7. Existence / D. Theories of Reality / 8. Facts / d. Negative facts
Facts can be both positive and negative [Wittgenstein, by Potter]
     Full Idea: In 1913 Wittgenstein was explicit that there are both positive and negative facts.
     From: report of Ludwig Wittgenstein (Notes on Logic [1913], B7) by Michael Potter - The Rise of Analytic Philosophy 1879-1930 47 'Mole'
     A reaction: This is a prelude to the Tractatus, in which negative facts are denied in T1.11 (and in a 1919 letter), but then affirmed in T2.06.
7. Existence / D. Theories of Reality / 11. Ontological Commitment / e. Ontological commitment problems
No scientific explanation would collapse if mathematical objects were shown not to exist [Chihara]
     Full Idea: Evidently, no scientific explanations of specific phenomena would collapse as a result of any hypothetical discovery that no mathematical objects exist.
     From: Charles Chihara (A Structural Account of Mathematics [2004], 09.1)
     A reaction: It is inconceivable that anyone would challenge this claim. A good model seems to be drama; a play needs commitment from actors and audience, even when we know it is fiction. The point is that mathematics doesn't collapse either.
If a successful theory confirms mathematics, presumably a failed theory disconfirms it? [Chihara]
     Full Idea: If mathematics shares whatever confirmation accrues to the theories using it, would it not be reasonable to suppose that mathematics shares whatever disconfirmation accrues to the theories using it?
     From: Charles Chihara (A Structural Account of Mathematics [2004], 05.8)
     A reaction: Presumably Quine would bite the bullet here, although maths is much closer to the centre of his web of belief, and so far less likely to require adjustment. In practice, though, mathematics is not challenged whenever an experiment fails.
8. Modes of Existence / C. Powers and Dispositions / 6. Dispositions / a. Dispositions
Once we know the mechanism of a disposition, we can eliminate 'similarity' [Quine]
     Full Idea: Once we can legitimize a disposition term by defining the relevant similarity standard, we are apt to know the mechanism of the disposition, and so by-pass the similarity.
     From: Willard Quine (Natural Kinds [1969], p.135)
     A reaction: I love mechanisms, but can we characterise mechanisms without mentioning powers and dispositions? Quine's dream is to eliminate 'similarity'.
8. Modes of Existence / C. Powers and Dispositions / 6. Dispositions / d. Dispositions as occurrent
We judge things to be soluble if they are the same kind as, or similar to, things that do dissolve [Quine]
     Full Idea: Intuitively, what qualifies a thing as soluble though it never gets into water is that it is of the same kind as the things that actually did or will dissolve; it is similar to them.
     From: Willard Quine (Natural Kinds [1969], p.130)
     A reaction: If you can judge that the similar things 'will' dissolve, you can cut to the chase and judge that this thing will dissolve.
14. Science / A. Basis of Science / 3. Experiment
Science is common sense, with a sophisticated method [Quine]
     Full Idea: Sciences differ from common sense only in the degree of methodological sophistication.
     From: Willard Quine (Natural Kinds [1969], p.129)
     A reaction: Science is normal thinking about the world, but it is teamwork, with the bar set very high.
14. Science / C. Induction / 1. Induction
Induction relies on similar effects following from each cause [Quine]
     Full Idea: Induction expresses our hopes that similar causes will have similar effects.
     From: Willard Quine (Natural Kinds [1969], p.125)
     A reaction: Some top philosophers are also top teachers, and Quine was one of them, in his writings. He boils it down for the layman. Once again, he is pointing to the fundamental role of the similarity relation.
Induction is just more of the same: animal expectations [Quine]
     Full Idea: Induction is essentially only more of the same: animal expectation or habit formation.
     From: Willard Quine (Natural Kinds [1969], p.125)
     A reaction: My working definition of induction is 'learning from experience', but that doesn't disagree with Quine. Lipton has a richer account of different types of induction. Quine's point is that it rests on resemblance.
14. Science / C. Induction / 5. Paradoxes of Induction / a. Grue problem
Grue is a puzzle because the notions of similarity and kind are dubious in science [Quine]
     Full Idea: What makes Goodman's example a puzzle is the dubious scientific standing of a general notion of similarity, or of kind.
     From: Willard Quine (Natural Kinds [1969], p.116)
     A reaction: Illuminating. It might be best expressed as revealing a problem with sortal terms, as employed by Geach, or by Wiggins. Grue is a bit silly, but sortals are subject to convention and culture. 'Natural' properties seem needed.
15. Nature of Minds / C. Capacities of Minds / 7. Seeing Resemblance
General terms depend on similarities among things [Quine]
     Full Idea: The usual general term, whether a common noun or a verb or an adjective, owes its generality to some resemblance among the things referred to.
     From: Willard Quine (Natural Kinds [1969], p.116)
     A reaction: Quine has a nice analysis of the basic role of similarity in a huge amount of supposedly strict scientific thought.
To learn yellow by observation, must we be told to look at the colour? [Quine]
     Full Idea: According to the 'respects' view, our learning of yellow by ostension would have depended on our first having been told or somehow apprised that it was going to be a question of color.
     From: Willard Quine (Natural Kinds [1969], p.122)
     A reaction: Quine suggests there is just one notion of similarity, and respects can be 'abstracted' afterwards. Even the ontologically ruthless Quine admits psychological abstraction!
Standards of similarity are innate, and the spacing of qualities such as colours can be mapped [Quine]
     Full Idea: A standard of similarity is in some sense innate. The spacing of qualities (such as red, pink and blue) can be explored and mapped in the laboratory by experiments. They are needed for all learning.
     From: Willard Quine (Natural Kinds [1969], p.123)
     A reaction: This reasserts Hume's original point in more scientific terms. It is one of the undeniable facts about our perceptions of qualities and properties, no matter how platonist your view of universals may be.
Similarity is just interchangeability in the cosmic machine [Quine]
     Full Idea: Things are similar to the extent that they are interchangeable parts of the cosmic machine.
     From: Willard Quine (Natural Kinds [1969], p.134)
     A reaction: This is a major idea for Quine, because it is a means to gradually eliminate the fuzzy ideas of 'resemblance' or 'similarity' or 'natural kind' from science. I love it! Two tigers are same insofar as they are substitutable.
18. Thought / E. Abstraction / 7. Abstracta by Equivalence
I prefer the open sentences of a Constructibility Theory, to Platonist ideas of 'equivalence classes' [Chihara]
     Full Idea: What I refer to as an 'equivalence class' (of line segments of a particular length) is an open sentence in my Constructibility Theory. I just use this terminology of the Platonist for didactic purposes.
     From: Charles Chihara (A Structural Account of Mathematics [2004], 09.10)
     A reaction: This is because 'equivalence classes' is committed to the existence of classes, which is Quinean Platonism. I am with Chihara in wanting a story that avoids such things. Kit Fine is investigating similar notions of rules of construction.
19. Language / B. Reference / 3. Direct Reference / b. Causal reference
Mathematical entities are causally inert, so the causal theory of reference won't work for them [Chihara]
     Full Idea: Causal theories of reference seem doomed to failure for the case of reference to mathematical entities, since such entities are evidently causally inert.
     From: Charles Chihara (A Structural Account of Mathematics [2004], 01.3)
     A reaction: Presumably you could baptise a fictional entity such as 'Polonius', and initiate a social causal chain, with a tradition of reference. You could baptise a baby in absentia.
19. Language / C. Assigning Meanings / 3. Predicates
Projectible predicates can be universalised about the kind to which they refer [Quine]
     Full Idea: 'Projectible' predicates are predicates F and G whose shared instances all do count, for whatever reason, towards confirmation of 'All F are G'. ….A projectible predicate is one that is true of all and only the things of a kind.
     From: Willard Quine (Natural Kinds [1969], p.115-6)
     A reaction: Both Quine and Goodman are infuriatingly brief about the introduction of this concept. 'Red' is true of all ripe tomatoes, but not 'only' of them. Hardly any predicates are true only of one kind. Is that a scholastic 'proprium'?
26. Natural Theory / B. Natural Kinds / 1. Natural Kinds
Quine probably regrets natural kinds now being treated as essences [Quine, by Dennett]
     Full Idea: The concept of natural kinds was reintroduced by Quine, who may now regret the way it has become a stand-in for the dubious but covertly popular concept of essences.
     From: report of Willard Quine (Natural Kinds [1969]) by Daniel C. Dennett - Consciousness Explained 12.2 n2
     A reaction: He is right that Quine would regret it, and he is right that we can't assume that there are necessary essences just because there seem to be stable natural kinds, but personally I am an essentialist, so I'm not that bothered.
If similarity has no degrees, kinds cannot be contained within one another [Quine]
     Full Idea: If similarity has no degrees there is no containing of kinds within broader kinds. If colored things are a kind, they are similar, but red things are too narrow for a kind. If red things are a kind, colored things are not similar, and it's too broad.
     From: Willard Quine (Natural Kinds [1969], p.118)
     A reaction: [compressed] I'm on Quine's side with this. We glibly talk of 'kinds', but the criteria for sorting things into kinds seems to be a mess. Quine goes on to offer a better account than the (diadic, yes-no) one rejected here.
Comparative similarity allows the kind 'colored' to contain the kind 'red' [Quine]
     Full Idea: With the triadic relation of comparative similarity, kinds can contain one another, as well as overlapping. Red and colored things can both count as kinds. Colored things all resemble one another, even though less than red things do.
     From: Willard Quine (Natural Kinds [1969], p.119)
     A reaction: [compressed] Quine claims that comparative similarity is necessary for kinds - that there be some 'foil' in a similarity - that A is more like C than B is.
26. Natural Theory / B. Natural Kinds / 3. Knowing Kinds
You can't base kinds just on resemblance, because chains of resemblance are a muddle [Quine]
     Full Idea: If kinds are based on similarity, this has the Imperfect Community problem. Red round, red wooden and round wooden things all resemble one another somehow. There may be nothing outside the set resembling them, so it meets the definition of kind.
     From: Willard Quine (Natural Kinds [1969], p.120)
     A reaction: [ref. to Goodman 'Structure' 2nd 163- , which attacks Carnap on this] This suggests an invocation of Wittgenstein's family resemblance, which won't be much help for natural kinds.
26. Natural Theory / D. Laws of Nature / 4. Regularities / a. Regularity theory
It is hard to see how regularities could be explained [Quine]
     Full Idea: Why there have been regularities is an obscure question, for it is hard to see what would count as an answer.
     From: Willard Quine (Natural Kinds [1969], p.126)
     A reaction: This is the standard pessimism of the 20th century Humeans, but it strikes me as comparable to the pessimism about science found in Locke and Hume. Regularities are explained all the time by scientists, though the lowest level may be hopeless.
27. Natural Reality / B. Modern Physics / 4. Standard Model / a. Concept of matter
'Gunk' is an individual possessing no parts that are atoms [Chihara]
     Full Idea: An 'atomless gunk' is defined to be an individual possessing no parts that are atoms.
     From: Charles Chihara (A Structural Account of Mathematics [2004], App A)
     A reaction: [Lewis coined it] If you ask what are a-toms made of and what are ideas made of, the only answer we can offer is that the a-toms are made of gunk, and the ideas aren't made of anything, which is still bad news for the existence of ideas.