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All the ideas for 'Scientific Explanation', 'The Structure of Objects' and 'Principia Mathematica'

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49 ideas

2. Reason / F. Fallacies / 4. Circularity
One sort of circularity presupposes a premise, the other presupposes a rule being used [Braithwaite, by Devitt]
     Full Idea: An argument is 'premise-circular' if it aims to establish a conclusion that is assumed as a premise of that very argument. An argument is 'rule-circular' if it aims to establish a conclusion that asserts the goodness of the rule used in that argument.
     From: report of R.B. Braithwaite (Scientific Explanation [1953], p.274-8) by Michael Devitt - There is no a Priori §2
     A reaction: Rule circularity is the sort of thing Quine is always objecting to, but such circularities may be unavoidable, and even totally benign. All the good things in life form a mutually supporting team.
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / e. Axioms of PL
The best known axiomatization of PL is Whitehead/Russell, with four axioms and two rules [Russell/Whitehead, by Hughes/Cresswell]
     Full Idea: The best known axiomatization of PL is Whitehead/Russell. There are four axioms: (p∨p)→p, q→(p∨q), (p→q)→(q∨p), and (q→r)→((p∨q)→(p∨r)), plus Substitution and Modus Ponens rules.
     From: report of B Russell/AN Whitehead (Principia Mathematica [1913]) by GE Hughes/M Cresswell - An Introduction to Modal Logic Ch.1
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / p. Axiom of Reducibility
Russell saw Reducibility as legitimate for reducing classes to logic [Linsky,B on Russell/Whitehead]
     Full Idea: The axiom of Reducibility ...is crucial in the reduction of classes to logic, ...and seems to be a quite legitimate logical notion for Russell.
     From: comment on B Russell/AN Whitehead (Principia Mathematica [1913]) by Bernard Linsky - Russell's Metaphysical Logic 6.4
     A reaction: This is an unusual defence of the axiom, which is usually presumed to have been kicked into the long grass by Quine. If one could reduce classes to logic, that would destroy the opposition to logicism in a single neat coup.
4. Formal Logic / F. Set Theory ST / 8. Critique of Set Theory
Russell denies extensional sets, because the null can't be a collection, and the singleton is just its element [Russell/Whitehead, by Shapiro]
     Full Idea: Russell adduces two reasons against the extensional view of classes, namely the existence of the null class (which cannot very well be a collection), and the unit classes (which would have to be identical with their single elements).
     From: report of B Russell/AN Whitehead (Principia Mathematica [1913]) by Stewart Shapiro - Structure and Ontology p.459
     A reaction: Gödel believes in the reality of classes. I have great sympathy with Russell, when people start to claim that sets are not just conveniences to help us think about things, but actual abstract entities. Is the singleton of my pencil is on this table?
We regard classes as mere symbolic or linguistic conveniences [Russell/Whitehead]
     Full Idea: Classes, so far as we introduce them, are merely symbolic or linguistic conveniences, not genuine objects.
     From: B Russell/AN Whitehead (Principia Mathematica [1913], p.72), quoted by Penelope Maddy - Naturalism in Mathematics III.2
4. Formal Logic / G. Formal Mereology / 1. Mereology
The 'aggregative' objections says mereology gets existence and location of objects wrong [Koslicki]
     Full Idea: The 'aggregative' objection to classical extensional mereology is that it assigns simply the wrong, set-like conditions of existence and spatio-temporal location to ordinary material objects.
     From: Kathrin Koslicki (The Structure of Objects [2008], 5.1)
     A reaction: [She attributes this to Kit Fine] The point is that there is more to a whole than just some parts, otherwise you could scatter the parts across the globe (or even across time) and claim that the object still existed. It's obvious really.
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
Consequence is truth-preserving, either despite substitutions, or in all interpretations [Koslicki]
     Full Idea: Two conceptions of logical consequence: a substitutional account, where no substitution of non-logical terms for others (of the right syntactic category) produce true premises and false conclusions; and model theory, where no interpretation can do it.
     From: Kathrin Koslicki (The Structure of Objects [2008], 9.3.2 n8)
     A reaction: [compressed]
5. Theory of Logic / B. Logical Consequence / 4. Semantic Consequence |=
'Roses are red; therefore, roses are colored' seems truth-preserving, but not valid in a system [Koslicki]
     Full Idea: 'Roses are red; therefore, roses are colored' may be necessarily truth-preserving, but it would not be classified as logically valid by standard systems of logic.
     From: Kathrin Koslicki (The Structure of Objects [2008], 9.3.2)
5. Theory of Logic / B. Logical Consequence / 7. Strict Implication
Lewis's 'strict implication' preserved Russell's confusion of 'if...then' with implication [Quine on Russell/Whitehead]
     Full Idea: Russell call 'if...then' implication, when the material conditional is a much better account; C.I.Lewis (in founding modern modal logic) preserved Russell's confusion by creating 'strict implication', and called that implication.
     From: comment on B Russell/AN Whitehead (Principia Mathematica [1913]) by Willard Quine - Reply to Professor Marcus p.177
     A reaction: [A compession of Quine's paragraph]. All of this assumes that logicians can give an accurate account of what if...then means, when ordinary usage is broad and vague. Strict implication seems to drain all the normal meaning out of 'if...then'.
Russell's implication means that random sentences imply one another [Lewis,CI on Russell/Whitehead]
     Full Idea: In Mr Russell's idea of implication, if twenty random sentences from a newspaper were put in a hat, and two of them drawn at random, one will certainly imply the other, and it is an even bet the implication will be mutual.
     From: comment on B Russell/AN Whitehead (Principia Mathematica [1913]) by C.I. Lewis - A Pragmatic Conception of the A Priori p.366
     A reaction: This sort of lament leads modern logicians to suggest 'relevance' as an important criterion. It certainly seems odd that so-called 'classical logic' should contain a principle so at variance with everyday reasoning.
5. Theory of Logic / C. Ontology of Logic / 1. Ontology of Logic
Russell unusually saw logic as 'interpreted' (though very general, and neutral) [Russell/Whitehead, by Linsky,B]
     Full Idea: Russell did not view logic as an uninterpreted calculus awaiting interpretations [the modern view]. Rather, logic is a single 'interpreted' body of a priori truths, of propositions rather than sentence forms - but maximally general and topic neutral.
     From: report of B Russell/AN Whitehead (Principia Mathematica [1913]) by Bernard Linsky - Russell's Metaphysical Logic 1
     A reaction: This is the view which Wittgenstein challenged, saying logic is just conventional. Linsky claims that Russell's logicism is much more plausible, once you understand his view of logic.
5. Theory of Logic / E. Structures of Logic / 6. Relations in Logic
In 'Principia' a new abstract theory of relations appeared, and was applied [Russell/Whitehead, by Gödel]
     Full Idea: In 'Principia' a young science was enriched with a new abstract theory of relations, ..and not only Cantor's set theory but also ordinary arithmetic and the theory of measurement are treated from this abstract relational standpoint.
     From: report of B Russell/AN Whitehead (Principia Mathematica [1913]) by Kurt Gödel - Russell's Mathematical Logic p.448
     A reaction: I presume this is accounting for relations in terms of ordered sets.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / i. Reals from cuts
A real number is the class of rationals less than the number [Russell/Whitehead, by Shapiro]
     Full Idea: For Russell the real number 2 is the class of rationals less than 2 (i.e. 2/1). ...Notice that on this definition, real numbers are classes of rational numbers.
     From: report of B Russell/AN Whitehead (Principia Mathematica [1913]) by Stewart Shapiro - Thinking About Mathematics 5.2
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / a. Defining numbers
Russell takes numbers to be classes, but then reduces the classes to numerical quantifiers [Russell/Whitehead, by Bostock]
     Full Idea: Although Russell takes numbers to be certain classes, his 'no-class' theory then eliminates all mention of classes in favour of the 'propositional functions' that define them; and in the case of the numbers these just are the numerical quantifiers.
     From: report of B Russell/AN Whitehead (Principia Mathematica [1913]) by David Bostock - Philosophy of Mathematics 9.B.4
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / e. Structuralism critique
Some questions concern mathematical entities, rather than whole structures [Koslicki]
     Full Idea: Those who hold that not all mathematical questions can be concerned with structural matters can point to 'why are π or e transcendental?' or 'how are the prime numbers distributed?' as questions about particular features in the domain.
     From: Kathrin Koslicki (The Structure of Objects [2008], 9.3.1 n6)
     A reaction: [She cites Mac Lane on this] The reply would have to be that we only have those particular notions because we have abstracted them from structures, as in deriving π for circles.
6. Mathematics / C. Sources of Mathematics / 6. Logicism / a. Early logicism
Russell and Whitehead took arithmetic to be higher-order logic [Russell/Whitehead, by Hodes]
     Full Idea: Russell and Whitehead took arithmetic to be higher-order logic, ..and came close to identifying numbers with numerical quantifiers.
     From: report of B Russell/AN Whitehead (Principia Mathematica [1913]) by Harold Hodes - Logicism and Ontological Commits. of Arithmetic p.148
     A reaction: The point here is 'higher-order'.
Russell and Whitehead were not realists, but embraced nearly all of maths in logic [Russell/Whitehead, by Friend]
     Full Idea: Unlike Frege, Russell and Whitehead were not realists about mathematical objects, and whereas Frege thought that only arithmetic and analysis are branches of logic, they think the vast majority of mathematics (including geometry) is essentially logical.
     From: report of B Russell/AN Whitehead (Principia Mathematica [1913]) by Michčle Friend - Introducing the Philosophy of Mathematics 3.1
     A reaction: If, in essence, Descartes reduced geometry to algebra (by inventing co-ordinates), then geometry ought to be included. It is characteristic of Russell's hubris to want to embrace everything.
'Principia' lacks a precise statement of the syntax [Gödel on Russell/Whitehead]
     Full Idea: What is missing, above all, in 'Principia', is a precise statement of the syntax of the formalism.
     From: comment on B Russell/AN Whitehead (Principia Mathematica [1913]) by Kurt Gödel - Russell's Mathematical Logic p.448
6. Mathematics / C. Sources of Mathematics / 6. Logicism / b. Type theory
The ramified theory of types used propositional functions, and covered bound variables [Russell/Whitehead, by George/Velleman]
     Full Idea: Russell and Whitehead's ramified theory of types worked not with sets, but with propositional functions (similar to Frege's concepts), with a more restrictive assignment of variables, insisting that bound, as well as free, variables be of lower type.
     From: report of B Russell/AN Whitehead (Principia Mathematica [1913]) by A.George / D.J.Velleman - Philosophies of Mathematics Ch.3
     A reaction: I don't fully understand this (and no one seems much interested any more), but I think variables are a key notion, and there is something interesting going on here. I am intrigued by ordinary language which behaves like variables.
The Russell/Whitehead type theory was limited, and was not really logic [Friend on Russell/Whitehead]
     Full Idea: The Russell/Whitehead type theory reduces mathematics to a consistent founding discipline, but is criticised for not really being logic. They could not prove the existence of infinite sets, and introduced a non-logical 'axiom of reducibility'.
     From: comment on B Russell/AN Whitehead (Principia Mathematica [1913]) by Michčle Friend - Introducing the Philosophy of Mathematics 3.6
     A reaction: To have reduced most of mathematics to a founding discipline sounds like quite an achievement, and its failure to be based in pure logic doesn't sound too bad. However, it seems to reduce some maths to just other maths.
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
In 'Principia Mathematica', logic is exceeded in the axioms of infinity and reducibility, and in the domains [Bernays on Russell/Whitehead]
     Full Idea: In the system of 'Principia Mathematica', it is not only the axioms of infinity and reducibility which go beyond pure logic, but also the initial conception of a universal domain of individuals and of a domain of predicates.
     From: comment on B Russell/AN Whitehead (Principia Mathematica [1913], p.267) by Paul Bernays - On Platonism in Mathematics p.267
     A reaction: This sort of criticism seems to be the real collapse of the logicist programme, rather than Russell's paradox, or Gödel's Incompleteness Theorems. It just became impossible to stick strictly to logic in the reduction of arithmetic.
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / a. Constructivism
Russell and Whitehead consider the paradoxes to indicate that we create mathematical reality [Russell/Whitehead, by Friend]
     Full Idea: Russell and Whitehead are particularly careful to avoid paradox, and consider the paradoxes to indicate that we create mathematical reality.
     From: report of B Russell/AN Whitehead (Principia Mathematica [1913]) by Michčle Friend - Introducing the Philosophy of Mathematics 3.1
     A reaction: This strikes me as quite a good argument. It is certainly counterintuitive that reality, and abstractions from reality, would contain contradictions. The realist view would be that we have paradoxes because we have misdescribed the facts.
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / d. Predicativism
To avoid vicious circularity Russell produced ramified type theory, but Ramsey simplified it [Russell/Whitehead, by Shapiro]
     Full Idea: Russell insisted on the vicious circle principle, and thus rejected impredicative definitions, which resulted in an unwieldy ramified type theory, with the ad hoc axiom of reducibility. Ramsey's simpler theory was impredicative and avoided the axiom.
     From: report of B Russell/AN Whitehead (Principia Mathematica [1913]) by Stewart Shapiro - Thinking About Mathematics 5.2
     A reaction: Nowadays the theory of types seems to have been given up, possibly because it has no real attraction if it lacks the strict character which Russell aspired to.
8. Modes of Existence / A. Relations / 3. Structural Relations
Structures have positions, constituent types and number, and some invariable parts [Koslicki]
     Full Idea: Structures make available positions or places for objects, and place restraints on the type of constituent, and on their configuration. ...These lead to restrictions on the number of objects, and on which parts of the structure are invariable.
     From: Kathrin Koslicki (The Structure of Objects [2008], 9.6)
     A reaction: [compressed] That's a pretty good first shot at saying what a structure is, which I have so far not discovered any other writer willing to do. I take this to be an exploration of what Aristotle meant by 'form'.
8. Modes of Existence / B. Properties / 6. Categorical Properties
'Categorical' properties exist in the actual world, and 'hypothetical' properties in other worlds [Koslicki]
     Full Idea: The 'categorical' properties are roughly those that concern what goes on in the actual world; the properties excluded from that family are the 'hypothetical' ones, which concern what goes on in other worlds.
     From: Kathrin Koslicki (The Structure of Objects [2008], 3.2.3.1)
     A reaction: The awkward guest at this little party is the 'dispositional' properties, which are held to exist in the actual world, but have implications for other worlds. I'm a fan of them.
9. Objects / B. Unity of Objects / 1. Unifying an Object / a. Intrinsic unification
I aim to put the notion of structure or form back into the concepts of part, whole and object [Koslicki]
     Full Idea: My project is to put the notion of structure or form squarely back at the center of any adequate account of the notion of part, whole and object.
     From: Kathrin Koslicki (The Structure of Objects [2008], Intro)
     A reaction: Excellent. It is the fault of logicians, who presumably can't cope with such elusive and complex concepts, that we have ended up with objects as lists of things or properties, or quantifications over them.
If a whole is just a structure, a dinner party wouldn't need the guests to turn up [Koslicki]
     Full Idea: If a whole is just a structure, we wonder how the guests could really be part of the dinner party seating structure, when the complex whole is fully exhausted by the structure that specifies the slots.
     From: Kathrin Koslicki (The Structure of Objects [2008], 4.2.2)
     A reaction: This cuts both ways. A dinner party may necessarily require guests, but the seating plan can be specified in the absence of any guests, who may never turn up. A seating plan is not a dinner party. Perhaps we have two objects here.
9. Objects / B. Unity of Objects / 3. Unity Problems / c. Statue and clay
The clay is just a part of the statue (its matter); the rest consists of its form or structure [Koslicki]
     Full Idea: That objects are compounds of matter and form yields a solution to the Problem of Constitution: the clay is merely a proper part of the statue (viz. its matter); the 'remainder' of the statue is its formal or structural components which distinguish it.
     From: Kathrin Koslicki (The Structure of Objects [2008], Info)
     A reaction: Thus philosophers have thought that it might consist of two objects because they have failed to grasp what an 'object' is. I would add that we need to mention 'essence', so that the statue can survive minor modifications. This is the solution!
Statue and clay differ in modal and temporal properties, and in constitution [Koslicki]
     Full Idea: The statue and the clay appear to differ in modal properties (such as being able to survive squashing), and temporal properties (coming into existence after the lump of clay), and in constitution (only the statue is constituted of the clay).
     From: Kathrin Koslicki (The Structure of Objects [2008], 7.2.7.2)
     A reaction: I think the modal properties are the biggest problem here. You can't say a thing and its constitution are different objects, as they are necessarily connected. Structure comes into existence at t, but the structure isn't the whole object.
9. Objects / C. Structure of Objects / 2. Hylomorphism / c. Form as causal
Structure or form are right at the centre of modern rigorous modes of enquiry [Koslicki]
     Full Idea: The notion of structure or form, far from being a mysterious and causally inert invention of philosophers, lies at the very center of many scientific and other rigorous endeavours, such as mathematics, logic, linguistics, chemistry and music.
     From: Kathrin Koslicki (The Structure of Objects [2008], Intro)
     A reaction: This echoes my own belief exactly, and places Aristotle at the centre of the modern stage. Her list of subjects is intriguing, and will need a bit of thought.
9. Objects / C. Structure of Objects / 6. Constitution of an Object
There are at least six versions of constitution being identity [Koslicki]
     Full Idea: The view that constitution is identity has many versions: eliminativism (van Inwagen), identity relative to time (Gallois), identity relativized to sort (Geach), four-dimensionalism (Lewis, Sider), contingent identity (Gibbard), dominant kinds (Burke).
     From: Kathrin Koslicki (The Structure of Objects [2008], 7.2.7.2 n17)
     A reaction: [she offers other names- useful footnote] Eliminativism says there is no identity. Gallois's view is Heraclitus. Geach seems to deny nature, since sorts are partly conventional. 4-D, nah! Gibbard: it could be the thing but lack its identity? Kinds wrong.
9. Objects / C. Structure of Objects / 8. Parts of Objects / a. Parts of objects
For three-dimensionalist parthood must be a three-place relation, including times [Koslicki]
     Full Idea: Parthood (for the three-dimensionalist) must be a three-place relation between pairs of objects and times, not the timeless two-place relation at work in the original Calculus of Individuals.
     From: Kathrin Koslicki (The Structure of Objects [2008], 2.2)
The parts may be the same type as the whole, like a building made of buildings [Koslicki]
     Full Idea: A building may be composed of proper parts which are themselves buildings; a particular pattern may be composed of proper parts which are themselves patterns (even the same pattern, on a smaller scale).
     From: Kathrin Koslicki (The Structure of Objects [2008], 7.2.12)
     A reaction: This strikes me as a rather important observation, if you are (erroneously) trying to establish the identity of a thing simply by categorising its type.
9. Objects / C. Structure of Objects / 8. Parts of Objects / c. Wholes from parts
Wholes in modern mereology are intended to replace sets, so they closely resemble them [Koslicki]
     Full Idea: The modern theory of parts and wholes was intended primarily to replace set theory; in this way, wholes came out looking as much like sets as they possibly could, without set theory's commitment to an infinite hierarchy of abstract objects.
     From: Kathrin Koslicki (The Structure of Objects [2008], Intro)
     A reaction: A very nice clarificatory remark, which explains well this rather baffling phenomenon of people who think there is nothing more to a whole than a pile of parts, as if a scrap heap were the same as a fleet of motor cars.
Wholes are entities distinct from their parts, and have different properties [Koslicki]
     Full Idea: A commitment to wholes is a commitment to entities that are numerically distinct from their parts (by Leibniz's Law, they don't share all of their properties - the parts typically exist, but the whole doesn't, prior to its creation).
     From: Kathrin Koslicki (The Structure of Objects [2008], 3.1)
     A reaction: Presumably in classical mereology no act of 'creation' is needed, since all the parts in the universe already form all the possible wholes into which they might combine, however bizarrely.
Wholes are not just their parts; a whole is an entity distinct from the proper parts [Koslicki]
     Full Idea: In my approach (as in that of Plato and Aristotle), wholes are in no way identified with parts; rather, a commitment to wholes is a commitment to entities numerically distinct from their proper parts.
     From: Kathrin Koslicki (The Structure of Objects [2008], 7.2.11)
     A reaction: Calling the whole an 'entity' doesn't seem to capture it. She seems to think there are some extra parts, in addition to the material parts, that make something a whole. I think this might be a category mistake. A structure is an abstraction.
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
An object is identical with itself, and no different indiscernible object can share that [Russell/Whitehead, by Adams,RM]
     Full Idea: Trivially, the Identity of Indiscernibles says that two individuals, Castor and Pollux, cannot have all properties in common. For Castor must have the properties of being identical with Castor and not being identical with Pollux, which Pollux can't share.
     From: report of B Russell/AN Whitehead (Principia Mathematica [1913], I p.57) by Robert Merrihew Adams - Primitive Thisness and Primitive Identity 2
     A reaction: I suspect that either the property of being identical with itself is quite vacuous, or it is parasytic on primitive identity, or it is the criterion which is actually used to define identity. Either way, I don't find this claim very illuminating.
12. Knowledge Sources / E. Direct Knowledge / 2. Intuition
Russell showed, through the paradoxes, that our basic logical intuitions are self-contradictory [Russell/Whitehead, by Gödel]
     Full Idea: By analyzing the paradoxes to which Cantor's set theory had led, ..Russell brought to light the amazing fact that our logical intuitions (concerning such notions as truth, concept, being, class) are self-contradictory.
     From: report of B Russell/AN Whitehead (Principia Mathematica [1913]) by Kurt Gödel - Russell's Mathematical Logic p.452
     A reaction: The main intuition that failed was, I take it, that every concept has an extension, that is, there are always objects which will or could fall under the concept.
18. Thought / A. Modes of Thought / 6. Judgement / a. Nature of Judgement
The multiple relations theory says assertions about propositions are about their ingredients [Russell/Whitehead, by Linsky,B]
     Full Idea: The multiple relations theory of judgement proposes that assertions about propositions are dependent upon genuine facts involving belief and other attitude relations, subjects of those attitudes, and the constituents of the belief.
     From: report of B Russell/AN Whitehead (Principia Mathematica [1913]) by Bernard Linsky - Russell's Metaphysical Logic 7.2
     A reaction: This seems to require a commitment to universals (especially relations) with which we can be directly acquainted. I prefer propositions, but as mental entities, not platonic entities.
A judgement is a complex entity, of mind and various objects [Russell/Whitehead]
     Full Idea: When a judgement occurs, there is a certain complex entity, composed of the mind and the various objects of the judgement.
     From: B Russell/AN Whitehead (Principia Mathematica [1913], p.44)
     A reaction: This is Russell's multiple-relation theory of judgement, which replaced his earlier belief in unified propositions (now 'false abstractions'). He seems to have accepted Locke's view, that the act of judgement produces the unity.
The meaning of 'Socrates is human' is completed by a judgement [Russell/Whitehead]
     Full Idea: When I judge 'Socrates is human', the meaning is completed by the act of judging.
     From: B Russell/AN Whitehead (Principia Mathematica [1913], p.44), quoted by Michael Morris - Guidebook to Wittgenstein's Tractatus
     A reaction: Morris says this is Russell's multiple-relations theory of judgement. The theory accompanies the rejection of the concept of the unified proposition. When I hear 'Socrates had a mole on his shoulder' I get the meaning without judging.
The multiple relation theory of judgement couldn't explain the unity of sentences [Morris,M on Russell/Whitehead]
     Full Idea: When Russell moved to his multiple relation theory of judgement …he then faced difficulties making sense of the unity of sentences.
     From: comment on B Russell/AN Whitehead (Principia Mathematica [1913], p.44) by Michael Morris - Guidebook to Wittgenstein's Tractatus 3A
     A reaction: Roughly, he seems committed to saying that there is only unity if you think there is unity; there is no unity in a sentence prior to the act of judgement.
Only the act of judging completes the meaning of a statement [Russell/Whitehead]
     Full Idea: When I judge 'Socrates is human', the meaning is completed by the act of judging, and we no longer have an incomplete symbol.
     From: B Russell/AN Whitehead (Principia Mathematica [1913], p.44), quoted by J. Alberto Coffa - The Semantic Tradition from Kant to Carnap
     A reaction: Personally I would have thought that you needed to know the meaning properly before you could make the judgement, but then he is Bertrand Russell and I'm not.
19. Language / D. Propositions / 3. Concrete Propositions
Propositions as objects of judgement don't exist, because we judge several objects, not one [Russell/Whitehead]
     Full Idea: A 'proposition', in the sense in which a proposition is supposed to be the object of a judgement, is a false abstraction, because a judgement has several objects, not one.
     From: B Russell/AN Whitehead (Principia Mathematica [1913], p.44), quoted by Michael Morris - Guidebook to Wittgenstein's Tractatus 2E
     A reaction: This is the rejection of the 'Russellian' theory of propositions, in favour of his multiple-relations theory of judgement. But why don't the related objects add up to a proposition about a state of affairs?
26. Natural Theory / B. Natural Kinds / 1. Natural Kinds
The Kripke/Putnam approach to natural kind terms seems to give them excessive stability [Koslicki]
     Full Idea: Theoretical terms such as 'mass', 'force', 'motion', 'species' and 'phlogiston' seem to indicate that the Kripke/Putnam approach to natural kind terms is committed to an excessive amount of stability in the meaning and reference of such expressions.
     From: Kathrin Koslicki (The Structure of Objects [2008], 8.6.2)
     A reaction: This sounds right to me. The notion of 'rigid' designation gives a nice framework for modal logic, but it doesn't seem to fit the shifting patterns of scientific thought.
26. Natural Theory / B. Natural Kinds / 3. Knowing Kinds
Natural kinds support inductive inferences, from previous samples to the next one [Koslicki]
     Full Idea: Natural kinds are said to stand out from other classifications because they support legitimate inductive inferences ...as when we observe that past samples of copper conduct electricity and infer that the next sample will too.
     From: Kathrin Koslicki (The Structure of Objects [2008], 8.3.1)
     A reaction: A slightly more precise version of the Upanishad definition of natural kinds which I favour (Idea 8153). If you can't predict the next one from the previous one, it isn't a natural kind. You can't quite predict the next tiger from the previous one.
26. Natural Theory / B. Natural Kinds / 4. Source of Kinds
Concepts for species are either intrinsic structure, or relations like breeding or ancestry [Koslicki]
     Full Idea: Candidate species concepts can be intrinsic: morphological, physiological or genetic similarity; or relational: biology such as interbreeding and reproductive isolation, ecology, such as mate recognition in a niche, or phylogenetics (ancestor relations).
     From: Kathrin Koslicki (The Structure of Objects [2008], 8.4.1)
     A reaction: She says the relational ones are more popular, but I gather they all hit problems. See John Dupré on the hopelessness of the whole task.
26. Natural Theory / B. Natural Kinds / 5. Reference to Natural Kinds
Should vernacular classifications ever be counted as natural kind terms? [Koslicki]
     Full Idea: It is controversial whether classificatory expressions from the vernacular should ever really be counted as genuine natural kind terms.
     From: Kathrin Koslicki (The Structure of Objects [2008], 8.2)
     A reaction: This is a similar confrontation between the folk and the scientific specialist as we find in folk psychology. There are good defences of folk psychology, and it looks plausible to defend the folk classifications as having priority.
26. Natural Theory / D. Laws of Nature / 11. Against Laws of Nature
There are apparently no scientific laws concerning biological species [Koslicki]
     Full Idea: It has been observed that there are apparently no scientific laws concerning biological species.
     From: Kathrin Koslicki (The Structure of Objects [2008], 8.4.1)
     A reaction: The central concept of biology I take to be a 'mechanism'. and I suspect that this view of science is actually applicable in physics and chemistry, with so-called 'laws' being a merely superficial description of what is going on.