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All the ideas for 'The Big Book of Concepts', 'Sets and Numbers' and 'The Philosophy of Logical Atomism'

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64 ideas

1. Philosophy / E. Nature of Metaphysics / 4. Metaphysics as Science
The business of metaphysics is to describe the world [Russell]
     Full Idea: It seems to me that the business of metaphysics is to describe the world.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §III)
     A reaction: At least he believed in metaphysics. Presumably he intends to describe the world in terms of its categories, rather than cataloguing every blade of grass.
2. Reason / B. Laws of Thought / 6. Ockham's Razor
Reducing entities and premisses makes error less likely [Russell]
     Full Idea: You diminish the risk of error with every diminution of entities and premisses.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §VIII)
     A reaction: If there are actually lots of entities, you would increase error if you reduced them too much. Ockham's Razor seems more to do with the limited capacity of the human mind than with the simplicity or complexity of reality. See Idea 4456.
3. Truth / B. Truthmakers / 5. What Makes Truths / a. What makes truths
Facts make propositions true or false, and are expressed by whole sentences [Russell]
     Full Idea: A fact is the kind of thing that makes a proposition true or false, …and it is the sort of thing that is expressed by a whole sentence, not by a single name like 'Socrates'.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §I)
     A reaction: It is important to note a point here which I consider vital - that Russell keeps the idea of a fact quite distinct from the language in which it is expressed. Facts are a 'sort of thing', of the kind which are now referred to as 'truth-makers'.
3. Truth / B. Truthmakers / 8. Making General Truths
Not only atomic truths, but also general and negative truths, have truth-makers [Russell, by Rami]
     Full Idea: In 1918 Russell held that beside atomic truths, also general and negative truths have truth-makers.
     From: report of Bertrand Russell (The Philosophy of Logical Atomism [1918]) by Adolph Rami - Introduction: Truth and Truth-Making note 04
4. Formal Logic / F. Set Theory ST / 3. Types of Set / c. Unit (Singleton) Sets
Normally a class with only one member is a problem, because the class and the member are identical [Russell]
     Full Idea: With the ordinary view of classes you would say that a class that has only one member was the same as that one member; that will land you in terrible difficulties, because in that case that one member is a member of that class, namely, itself.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §VII)
     A reaction: The problem (I think) is that classes (sets) were defined by Frege as being identical with their members (their extension). With hindsight this may have been a mistake. The question is always 'why is that particular a member of that set?'
4. Formal Logic / F. Set Theory ST / 7. Natural Sets
The master science is physical objects divided into sets [Maddy]
     Full Idea: The master science can be thought of as the theory of sets with the entire range of physical objects as ur-elements.
     From: Penelope Maddy (Sets and Numbers [1981], II)
     A reaction: This sounds like Quine's view, since we have to add sets to our naturalistic ontology of objects. It seems to involve unrestricted mereology to create normal objects.
5. Theory of Logic / E. Structures of Logic / 1. Logical Form
In a logically perfect language, there will be just one word for every simple object [Russell]
     Full Idea: In a logically perfect language, there will be one word and no more for every simple object.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §II)
     A reaction: In other words, there would be no universals, only names? All that matters is that a language can successfully refer (unambiguously) to anything it wishes to. There must be better ways than Russell's lexical explosion.
Romulus does not occur in the proposition 'Romulus did not exist' [Russell]
     Full Idea: Romulus does not occur in the proposition 'Romulus did not exist'.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §VI)
     A reaction: A very nice paradoxical assertion, which captures the problem of finding the logical form for negative existential statements. Presumably the proposition refers to the mythical founder of Rome, though. He is not, I suppose, rigidly designated.
5. Theory of Logic / F. Referring in Logic / 1. Naming / a. Names
You can understand 'author of Waverley', but to understand 'Scott' you must know who it applies to [Russell]
     Full Idea: If you understand English you would understand the phrase 'the author of Waverley' if you had not heard it before, whereas you would not understand the meaning of 'Scott', because to know the meaning of a name is to know who it is applied to.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §VI)
     A reaction: Actually, you would find 'Waverley' a bit baffling too. Would you understand "he was the author of his own destruction"? You can understand "Homer was the author of this" without knowing quite who 'Homer' applies to. All very tricky.
There are a set of criteria for pinning down a logically proper name [Russell, by Sainsbury]
     Full Idea: A logically proper name must be semantically simple, have just one referent, be understood by the user, be scopeless, is not a definite description, and rigidly designates.
     From: report of Bertrand Russell (The Philosophy of Logical Atomism [1918], 24th pg) by Mark Sainsbury - The Essence of Reference Intro
     A reaction: Famously, Russell's hopes of achieving this logically desirable end got narrower and narrower, and ended with 'this' or 'that'. Maybe pure language can't do the job.
5. Theory of Logic / F. Referring in Logic / 1. Naming / b. Names as descriptive
Treat description using quantifiers, and treat proper names as descriptions [Russell, by McCullogh]
     Full Idea: Having proposed that descriptions should be treated in quantificational terms, Russell then went on to introduce the subsidiary injunction that proper names should be treated as descriptions.
     From: report of Bertrand Russell (The Philosophy of Logical Atomism [1918]) by Gregory McCullogh - The Game of the Name 2.18
     A reaction: McCulloch says Russell 'has a lot to answer for' here. It became a hot topic with Kripke. Personally I find Lewis's notion of counterparts the most promising line of enquiry.
5. Theory of Logic / F. Referring in Logic / 1. Naming / e. Empty names
A name has got to name something or it is not a name [Russell]
     Full Idea: A name has got to name something or it is not a name.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], 66th pg), quoted by Mark Sainsbury - The Essence of Reference 18.2
     A reaction: This seems to be stipulative, since most people would say that a list of potential names for a baby counted as names. It may be wrong. There are fictional names, or mistakes.
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Set theory (unlike the Peano postulates) can explain why multiplication is commutative [Maddy]
     Full Idea: If you wonder why multiplication is commutative, you could prove it from the Peano postulates, but the proof offers little towards an answer. In set theory Cartesian products match 1-1, and n.m dots when turned on its side has m.n dots, which explains it.
     From: Penelope Maddy (Sets and Numbers [1981], II)
     A reaction: 'Turning on its side' sounds more fundamental than formal set theory. I'm a fan of explanation as taking you to the heart of the problem. I suspect the world, rather than set theory, explains the commutativity.
Standardly, numbers are said to be sets, which is neat ontology and epistemology [Maddy]
     Full Idea: The standard account of the relationship between numbers and sets is that numbers simply are certain sets. This has the advantage of ontological economy, and allows numbers to be brought within the epistemology of sets.
     From: Penelope Maddy (Sets and Numbers [1981], III)
     A reaction: Maddy votes for numbers being properties of sets, rather than the sets themselves. See Yourgrau's critique.
Numbers are properties of sets, just as lengths are properties of physical objects [Maddy]
     Full Idea: I propose that ...numbers are properties of sets, analogous, for example, to lengths, which are properties of physical objects.
     From: Penelope Maddy (Sets and Numbers [1981], III)
     A reaction: Are lengths properties of physical objects? A hole in the ground can have a length. A gap can have a length. Pure space seems to contain lengths. A set seems much more abstract than its members.
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / b. Mathematics is not set theory
Sets exist where their elements are, but numbers are more like universals [Maddy]
     Full Idea: A set of things is located where the aggregate of those things is located, ...but a number is simultaneously located at many different places (10 in my hand, and a baseball team) ...so numbers seem more like universals than particulars.
     From: Penelope Maddy (Sets and Numbers [1981], III)
     A reaction: My gut feeling is that Maddy's master idea (of naturalising sets by building them from ur-elements of natural objects) won't work. Sets can work fine in total abstraction from nature.
Number theory doesn't 'reduce' to set theory, because sets have number properties [Maddy]
     Full Idea: I am not suggesting a reduction of number theory to set theory ...There are only sets with number properties; number theory is part of the theory of finite sets.
     From: Penelope Maddy (Sets and Numbers [1981], V)
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / b. Against mathematical platonism
If mathematical objects exist, how can we know them, and which objects are they? [Maddy]
     Full Idea: The popular challenges to platonism in philosophy of mathematics are epistemological (how are we able to interact with these objects in appropriate ways) and ontological (if numbers are sets, which sets are they).
     From: Penelope Maddy (Sets and Numbers [1981], I)
     A reaction: These objections refer to Benacerraf's two famous papers - 1965 for the ontology, and 1973 for the epistemology. Though he relied too much on causal accounts of knowledge in 1973, I'm with him all the way.
6. Mathematics / C. Sources of Mathematics / 5. Numbers as Adjectival
Number words are unusual as adjectives; we don't say 'is five', and numbers always come first [Maddy]
     Full Idea: Number words are not like normal adjectives. For example, number words don't occur in 'is (are)...' contexts except artificially, and they must appear before all other adjectives, and so on.
     From: Penelope Maddy (Sets and Numbers [1981], IV)
     A reaction: [She is citing Benacerraf's arguments]
6. Mathematics / C. Sources of Mathematics / 9. Fictional Mathematics
Numbers are classes of classes, and hence fictions of fictions [Russell]
     Full Idea: Numbers are classes of classes, and classes are logical fictions, so that numbers are, as it were, fictions at two removes, fictions of fictions.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §VIII)
     A reaction: This summarises the findings of Russell and Whitehead's researches into logicism. Gödel may have proved that project impossible, but there is now debate about that. Personally I think of numbers as names of patterns.
7. Existence / C. Structure of Existence / 6. Fundamentals / d. Logical atoms
Russell's new logical atomist was of particulars, universals and facts (not platonic propositions) [Russell, by Linsky,B]
     Full Idea: Russell's new logical atomist ontology was of particulars, universals and facts, replacing the ontology of 'platonic atomism' consisting just of propositions.
     From: report of Bertrand Russell (The Philosophy of Logical Atomism [1918]) by Bernard Linsky - Russell's Metaphysical Logic 1
     A reaction: Linsky cites Peter Hylton as saying that the earlier view was never replaced. The earlier view required propositions to be 'unified'. I surmise that the formula 'Fa' combines a universal and a particular, to form an atomic fact. [...but Idea 6111!]
Russell's atomic facts are actually compounds, and his true logical atoms are sense data [Russell, by Quine]
     Full Idea: In 1918 Russell does not admit facts as fundamental; atomic facts are atomic as facts go, but they are compound objects. The atoms of Russell's logical atomism are not atomic facts but sense data.
     From: report of Bertrand Russell (The Philosophy of Logical Atomism [1918]) by Willard Quine - Russell's Ontological Development p.83
     A reaction: By about 1921 Russell had totally given up sense-data, because he had been reading behaviourist psychology.
Logical atomism aims at logical atoms as the last residue of analysis [Russell]
     Full Idea: I call my doctrine logical atomism because, as the last residue of analysis, I wish to arrive at logical atoms and not physical atoms; some of them will be particulars, and others will be predicates and relations and so on.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §I)
     A reaction: However we judge it, logical atomism is a vital landmark in the history of 'analytical' philosophy, because it lays out the ideal for our assessment. It is fashionable to denigrate analysis, but I think it is simply the nearest to wisdom we will ever get.
Once you have enumerated all the atomic facts, there is a further fact that those are all the facts [Russell]
     Full Idea: When you have enumerated all the atomic facts in the world, it is a further fact about the world that those are all the atomic facts there are about the world.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §V)
     A reaction: There is obviously a potential regress of facts about facts here. This looks like one of the reasons why the original logical atomism had a short shelf-life. Personally I see this as an argument in favour of rationalism, in the way Bonjour argues for it.
Logical atoms aims to get down to ultimate simples, with their own unique reality [Russell]
     Full Idea: Logical atomism is the view that you can get down in theory, if not in practice, to ultimate simples, out of which the world is built, and that those simples have a kind of reality not belonging to anything else.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §VIII)
     A reaction: This dream is to empiricists what the Absolute is to rationalists - a bit silly, but an embodiment of the motivating dream.
7. Existence / D. Theories of Reality / 8. Facts / a. Facts
You can't name all the facts, so they are not real, but are what propositions assert [Russell]
     Full Idea: Facts are the sort of things that are asserted or denied by propositions, and are not properly entities at all in the same sense in which their constituents are. That is shown by the fact that you cannot name them.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], p.235), quoted by Bernard Linsky - Russell's Metaphysical Logic 2.2
     A reaction: [ref to Papers vol.8] It is customary to specify a proposition by its capacity for T and F. So is a fact just 'a truth'? This contains the Fregean idea that things are only real if they can be picked out. I think of facts as independent of minds.
7. Existence / D. Theories of Reality / 8. Facts / b. Types of fact
Russell asserts atomic, existential, negative and general facts [Russell, by Armstrong]
     Full Idea: Russell argues for atomic facts, and also for existential facts, negative facts and general facts.
     From: report of Bertrand Russell (The Philosophy of Logical Atomism [1918]) by David M. Armstrong - Truth and Truthmakers 05.1
     A reaction: Armstrong says he overdoes it. I would even add disjunctive facts, which Russell rejects. 'Rain or snow will ruin the cricket match'. Rain can make that true, but it is a disjunctive fact about the match.
7. Existence / D. Theories of Reality / 9. States of Affairs
Modern trope theory tries, like logical atomism, to reduce things to elementary states [Russell, by Ellis]
     Full Idea: Russell and Wittgenstein sought to reduce everything to singular facts or states of affairs, and Armstrong and Keith Campbell have more recently advocated ontologies of tropes or elementary states of affairs.
     From: report of Bertrand Russell (The Philosophy of Logical Atomism [1918]) by Brian Ellis - The Philosophy of Nature: new essentialism Ch.3 n 11
     A reaction: A very interesting historical link. Logical atomism strikes me as a key landmark in the history of philosophy, and not an eccentric cul-de-sac. It is always worth trying to get your ontology down to minimal small units, to see what happens.
7. Existence / D. Theories of Reality / 11. Ontological Commitment / a. Ontological commitment
'Existence' means that a propositional function is sometimes true [Russell]
     Full Idea: When you take any propositional function and assert of it that it is possible, that it is sometimes true, that gives you the fundamental meaning of 'existence'.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918]), quoted by Colin McGinn - Logical Properties Ch.2
     A reaction: Functions depend on variables, so this leads to Quine's slogan "to be is to be the value of a variable". Assertions of non-existence are an obvious problem, but Russell thought of all that. All of this makes existence too dependent on language.
10. Modality / A. Necessity / 2. Nature of Necessity
Modal terms are properties of propositional functions, not of propositions [Russell]
     Full Idea: Traditional philosophy discusses 'necessary', 'possible' and 'impossible' as properties of propositions, whereas in fact they are properties of propositional functions; propositions are only true or false.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §V)
     A reaction: I am unclear how a truth could be known to be necessary if it is full of variables. 'x is human' seems to have no modality, but 'Socrates is human' could well be necessary. I like McGinn's rather adverbial account of modality.
12. Knowledge Sources / B. Perception / 5. Interpretation
Research shows perceptual discrimination is sharper at category boundaries [Murphy]
     Full Idea: Goldstone's research has shown how learning concepts can change perceptual units. For example, perceptual discrimination is heightened along category boundaries.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
     A reaction: [Goldstone 1994, 2000] This is just the sort of research which throws a spanner into the simplistic a priori thinking of many philosophers.
Perception goes straight to the fact, and not through the proposition [Russell]
     Full Idea: I am inclined to think that perception, as opposed to belief, does go straight to the fact and not through the proposition.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §IV.4)
     A reaction: There seems to be a question of an intermediate stage, which is the formulation of concepts. Is full 'perception' (backed by attention and intellect) laden with concepts, which point to facts? Where are the facts in sensation without recognition?
14. Science / C. Induction / 1. Induction
Induction is said to just compare properties of categories, but the type of property also matters [Murphy]
     Full Idea: Most theories of induction claim that it should depend primarily on the similarity of the categories involved, but then the type of property should not matter, yet research shows that it does.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 6)
     A reaction: I take this to be good empirical support for Gilbert Harman's view that induction is really inference to the best explanation. The thought (which strikes me as obviously correct) is that we bring nested domains of knowledge to bear in induction.
18. Thought / A. Modes of Thought / 6. Judgement / b. Error
The theory of error seems to need the existence of the non-existent [Russell]
     Full Idea: It is very difficult to deal with the theory of error without assuming the existence of the non-existent.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §IV.3)
     A reaction: This problem really bothered Russell (and Plato). I suspect that it was a self-inflicted problem because at this point Russell had ceased to believe in propositions. If we accept propositions as intentional objects, they can be as silly as you like.
18. Thought / D. Concepts / 1. Concepts / a. Nature of concepts
The main theories of concepts are exemplar, prototype and knowledge [Murphy]
     Full Idea: The three main theories of concepts under consideration are the exemplar, the prototype and the knowledge approaches.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
18. Thought / D. Concepts / 4. Structure of Concepts / c. Classical concepts
The theoretical and practical definitions for the classical view are very hard to find [Murphy]
     Full Idea: It has been extremely difficult to find definitions for most natural categories, and even harder to find definitions that are plausible psychological representations that people of all ages would be likely to use.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 2)
The classical definitional approach cannot distinguish typical and atypical category members [Murphy]
     Full Idea: The early psychological approaches to concepts took a definitional approach. ...but this view does not have any way of distinguishing typical and atypical category members (...as when a trout is a typical fish and an eel an atypical one).
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 2)
     A reaction: [pp. 12 and 22] Eleanor Rosch in the 1970s is said to have largely killed off the classical view.
Classical concepts follow classical logic, but concepts in real life don't work that way [Murphy]
     Full Idea: The classical view of concepts has been tied to traditional logic. 'Fido is a dog and a pet' is true if it has the necessary and sufficient conditions for both, ...but there is empirical evidence that people do not follow that rule.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 2)
     A reaction: Examples given are classifying chess as a sport and/or game, and classifying a tree house (which is agreed to be both a building and not a building!).
Classical concepts are transitive hierarchies, but actual categories may be intransitive [Murphy]
     Full Idea: The classical view of concepts explains hierarchical order, where categories form nested sets. But research shows that categories are often not transitive. Research shows that a seat is furniture, and a car seat is a seat, but it is not furniture.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 2)
     A reaction: [compressed] Murphy adds that the nesting of definitions is classically used to match the nesting of hierarchies. This is a nice example of the neatness of the analytic philosopher breaking down when it meets the mess of the world.
The classical core is meant to be the real concept, but actually seems unimportant [Murphy]
     Full Idea: A problem with the revised classical view is that the concept core does not seem to be an important part of the concept, despite its name and theoretical intention as representing the 'real' concept.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 2)
     A reaction: Apparently most researchers feel they can explain their results without reference to any core. Not so fast, I would say (being an essentialist). Maybe people acknowledge an implicit core without knowing what it is. See Susan Gelman.
18. Thought / D. Concepts / 4. Structure of Concepts / d. Concepts as prototypes
There is no 'ideal' bird or dog, and prototypes give no information about variability [Murphy]
     Full Idea: Is there really an 'ideal bird' that could represent all birds? ...Furthermore a single prototype would give no information about the variability of a category. ...Compare the incredible variety of dogs to the much smaller diversity of cats.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 3)
     A reaction: The point about variability is particularly noteworthy. You only grasp the concept of 'furniture' when you understand its range, as well as its typical examples. What structure is needed in a concept to achieve this?
Prototypes are unified representations of the entire category (rather than of members) [Murphy]
     Full Idea: In the prototype view the entire category is represented by a unified representation rather than separate representations for each member, or for different classes of members.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 3)
     A reaction: This is the improved prototype view, as opposed to the implausible idea that there is one ideal exemplar. The new theory still have the problem of how to represent diversity within the category, while somehow remaining 'unified'.
The prototype theory uses observed features, but can't include their construction [Murphy]
     Full Idea: Nothing in the prototype model says the shape of an animal is more important than its location in identifying its kind. The theory does not provide a way the features can be constructed, rather than just observed.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 6)
     A reaction: This makes some kind of mental modelling central to thought, and not just a bonus once you have empirically acquired the concepts. We bring our full range of experience to bear on even the most instantaneous observations.
The prototype theory handles hierarchical categories and combinations of concepts well [Murphy]
     Full Idea: The prototype view has no trouble with either hierarchical structure or explaining categories. ...Meaning and conceptual combination provide strong evidence for prototypes.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
     A reaction: Prototypes are not vague, making clearer classification possible. A 'mountain lion' is clear, because its components are clear.
Prototypes theory of concepts is best, as a full description with weighted typical features [Murphy]
     Full Idea: Our theory of concepts must be primarily prototype-based. That is, it must be a description of an entire concept, with its typical features (presumably weighted by their importance).
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
     A reaction: This is to be distinguished from the discredited 'classical' view of concepts, that the concept consists of its definition. I take Aristotle's account of definition to be closer to a prototype description than to a dictionary definition.
Learning concepts is forming prototypes with a knowledge structure [Murphy]
     Full Idea: My proposal is that people attempt to form prototypes as part of a larger knowledge structure when they learn concepts.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
     A reaction: This combines theory theory (knowledge) with the prototype view, and sounds rather persuasive. The formation of prototypes fits with the explanatory account of essentialism I am defending. He later calls prototype formation 'abstraction' (494).
18. Thought / D. Concepts / 4. Structure of Concepts / e. Concepts from exemplars
The most popular theories of concepts are based on prototypes or exemplars [Murphy]
     Full Idea: The most popular theories of concepts are based on prototype or exemplar theories that are strongly unclassical.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 2)
The exemplar view of concepts says 'dogs' is the set of dogs I remember [Murphy]
     Full Idea: In the exemplar view of concepts, the idea that people have a representation that somehow encompasses an entire concept is rejected. ...Instead a person's concept of dogs is the set of dogs that the person remembers.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 3)
     A reaction: [The theory was introduced by Medin and Schaffer 1978] I think I have finally met a plausible theory of concepts. When I think 'dog' I conjure up a fuzz of dogs that exhibit the range I have encountered (e.g. tiny to very big). Individuals come first!
Exemplar theory struggles with hierarchical classification and with induction [Murphy]
     Full Idea: The exemplar view has trouble with hierarchical classification and with induction in adults.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
     A reaction: To me these both strongly support essentialism - that you form the concept 'dog' from seeing some dogs, but you then extrapolate to large categories and general truths about dogs, on the assumption of the natures of the dogs you have seen.
Children using knowing and essentialist categories doesn't fit the exemplar view [Murphy]
     Full Idea: The findings showing that children use knowledge and may be essentialist about category membership do not comport well with the exemplar view.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
     A reaction: Tricky, because Gelman persuaded me of the essentialism, but the exemplar view of concepts looks the most promising. Clearly they must be forced to coexist....
Conceptual combination must be compositional, and can't be built up from exemplars [Murphy]
     Full Idea: The exemplar accounts of conceptual combination are demonstrably wrong, because the meaning of a phrase has to be composed from the meaning of its parts (plus broader knowledge), and it cannot be composed as a function of exemplars.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
     A reaction: This sounds quite persuasive, and I begin to see that my favoured essentialism fits the prototype view of concepts best, though this mustn't be interpreted too crudely. We change our prototypes with experience. 'Bird' is a tricky case.
The concept of birds from exemplars must also be used in inductions about birds [Murphy]
     Full Idea: We don't have one concept of birds formed by learning from exemplars, and another concept of birds that is used in induction.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch.13)
     A reaction: In other words exemplar concepts break down when we generalise using the concept. The exemplars must be unified, to be usable in thought and language.
18. Thought / D. Concepts / 4. Structure of Concepts / f. Theory theory of concepts
We do not learn concepts in isolation, but as an integrated part of broader knowledge [Murphy]
     Full Idea: The knowledge approach argues that concepts are part of our general knowledge about the world. We do not learn concepts in isolation, ...but as part of our overall understanding of the world. Animal concepts are integrated with biology, behaviour etc.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 3)
     A reaction: This is one of the leading theories of concepts among psychologists. It seems to be an aspect of the true theory, but it needs underpinning with some account of isolated individual concepts. This is also known as the 'theory theory'.
Concepts with familiar contents are easier to learn [Murphy]
     Full Idea: A concept's content influences how easy it is to learn. If the concept is grossly incompatible with what people know prior to the experiment, it will be difficult to acquire.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 6)
     A reaction: This is a preliminary fact which leads towards the 'knowledge' theory of concepts (aka 'theory theory'). The point being that the knowledge involved is integral to the concept. Fits my preferred mental files approach.
Some knowledge is involved in instant use of categories, other knowledge in explanations [Murphy]
     Full Idea: Some kinds of knowledge are probably directly incorporated into the category representation and used in normal, fast decisions about objects. Other kinds of knowledge, however, may come into play only when it has been solicited.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 6)
     A reaction: This is a summary of empirical research, but seems to fit our normal experience. If you see a hawk, you have some instant understanding, but if you ask what the hawk is doing here, you draw more widely.
People categorise things consistent with their knowledge, even rejecting some good evidence [Murphy]
     Full Idea: People tend to positively categorise items that are consistent with their knowledge and to exclude items that are inconsistent, sometimes even overruling purely empirical sources of information.
     From: Gregory L. Murphy (The Big Book of Concepts [2004], Ch. 6)
     A reaction: The main rival to 'theory theory' is the purely empirical account of how concepts are acquired. This idea reports empirical research in favour of the theory theory (or 'knowledge') approach.
19. Language / C. Assigning Meanings / 3. Predicates
Russell uses 'propositional function' to refer to both predicates and to attributes [Quine on Russell]
     Full Idea: Russell used the phrase 'propositional function' (adapted from Frege) to refer sometimes to predicates and sometimes to attributes.
     From: comment on Bertrand Russell (The Philosophy of Logical Atomism [1918]) by Willard Quine - Philosophy of Logic Ch.5
     A reaction: He calls Russell 'confused' on this, and he would indeed be guilty of what now looks like a classic confusion, between the properties and the predicates that express them. Only a verificationist would hold such a daft view.
19. Language / D. Propositions / 1. Propositions
Propositions don't name facts, because each fact corresponds to a proposition and its negation [Russell]
     Full Idea: It is obvious that a proposition is not the name for a fact, from the mere circumstance that there are two propositions corresponding to each fact, one the negation of the other.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §I)
     A reaction: Russell attributes this point to Wittgenstein. Evidently you must add that the proposition is true before it will name a fact - which is bad news for the redundancy view of truth. Couldn't lots of propositions correspond to one fact?
19. Language / D. Propositions / 3. Concrete Propositions
In 1918 still believes in nonlinguistic analogues of sentences, but he now calls them 'facts' [Russell, by Quine]
     Full Idea: In 1918 Russell insists that the world does contain nonlinguistic things that are akin to sentences and are asserted by them; he merely does not call them propositions. He calls them facts.
     From: report of Bertrand Russell (The Philosophy of Logical Atomism [1918]) by Willard Quine - Russell's Ontological Development p.81
     A reaction: Clarification! I have always been bewildered by the early Russell view of propositions as actual ingredients of the world. If we say that sentences assert facts, that makes more sense. Russell never believed in the mental entities I call 'propositions'.
19. Language / D. Propositions / 6. Propositions Critique
An inventory of the world does not need to include propositions [Russell]
     Full Idea: It is quite clear that propositions are not what you might call 'real'; if you were making an inventory of the world, propositions would not come in.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §III)
     A reaction: I am not clear why this is "quite clear". Propositions might even turn up in our ontology as physical objects (brain states). He says beliefs are real, but if you can't have a belief without a proposition, and they aren't real, you are in trouble.
I no longer believe in propositions, especially concerning falsehoods [Russell]
     Full Idea: Time was when I thought there were propositions, but it does not seem to me very plausible to say that in addition to facts there are also these curious shadowy things going about as 'That today is Wednesday' when in fact it is Tuesday.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §IV.2)
     A reaction: You need to give some account of someone who thinks 'Today is Wednesday' when it is Tuesday. We can hardly avoid talking about something like an 'intentional object', which can be expressed in a sentence. Are there not possible (formulable) propositions?
I know longer believe in shadowy things like 'that today is Wednesday' when it is actually Tuesday [Russell]
     Full Idea: Time was when I thought there were propositions, but it does not seem to me very plausible to say that in addition to facts there are also these curious shadowy things going about such 'That today is Wednesday' when it is in fact Tuesday.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], p.197), quoted by Bernard Linsky - Russell's Metaphysical Logic 3.1
     A reaction: [Ref to Papers v8] I take Russell to have abandoned his propositions because his conception of them was mistaken. Presumably my thinking 'Today is Wednesay' conjures up a false proposition, which had not previously existed.
19. Language / F. Communication / 4. Private Language
The names in a logically perfect language would be private, and could not be shared [Russell]
     Full Idea: A logically perfect language, if it could be constructed, would be, as regards its vocabulary, very largely private to one speaker; that is, all the names in it would be private to that speaker and could not enter into the language of another speaker.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §II)
     A reaction: Wittgenstein obviously thought there was something not quite right about this… See Idea 4147, for example. I presume Russell's thought is that you would have no means of explaining the 'meanings' of the names in the language.
28. God / B. Proving God / 2. Proofs of Reason / b. Ontological Proof critique
You can discuss 'God exists', so 'God' is a description, not a name [Russell]
     Full Idea: The fact that you can discuss the proposition 'God exists' is a proof that 'God', as used in that proposition, is a description and not a name. If 'God' were a name, no question as to its existence could arise.
     From: Bertrand Russell (The Philosophy of Logical Atomism [1918], §VI)
     A reaction: Presumably 'a being than which none greater can be conceived' (Anselm's definition) is self-evidently a description, and doesn't claim to be a name. Aquinas caps each argument with a triumphant naming of the being he has proved.