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All the ideas for 'Identity and Spatio-Temporal Continuity', 'Definitions' and 'Abstract Objects'

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21 ideas

2. Reason / D. Definition / 1. Definitions
Definitions usually have a term, a 'definiendum' containing the term, and a defining 'definiens' [Gupta]
     Full Idea: Many definitions have three elements: the term that is defined, an expression containing the defined term (the 'definiendum'), and another expression (the 'definiens') that is equated by the definition with this expression.
     From: Anil Gupta (Definitions [2008], 2)
     A reaction: He notes that the definiendum and the definiens are assumed to be in the 'same logical category', which is a right can of worms.
Notable definitions have been of piety (Plato), God (Anselm), number (Frege), and truth (Tarski) [Gupta]
     Full Idea: Notable examples of definitions in philosophy have been Plato's (e.g. of piety, in 'Euthyphro'), Anselm's definition of God, the Frege-Russell definition of number, and Tarski's definition of truth.
     From: Anil Gupta (Definitions [2008], Intro)
     A reaction: All of these are notable for the extensive metaphysical conclusions which then flow from what seems like a fairly neutral definition. We would expect that if we were defining essences, but not if we were just defining word usage.
2. Reason / D. Definition / 2. Aims of Definition
A definition needs to apply to the same object across possible worlds [Gupta]
     Full Idea: In a modal logic in which names are non-vacuous and rigid, not only must existence and uniqueness in a definition be shown to hold necessarily, it must be shown that the definiens is satisfied by the same object across possible worlds.
     From: Anil Gupta (Definitions [2008], 2.4)
The 'revision theory' says that definitions are rules for improving output [Gupta]
     Full Idea: The 'revision theory' of definitions says definitions impart a hypothetical character, giving a rule of revision rather than a rule of application. ...The output interpretation is better than the input one.
     From: Anil Gupta (Definitions [2008], 2.7)
     A reaction: Gupta mentions the question of whether such definitions can extend into the trans-finite.
2. Reason / D. Definition / 3. Types of Definition
Traditional definitions are general identities, which are sentential and reductive [Gupta]
     Full Idea: Traditional definitions are generalized identities (so definiendum and definiens can replace each other), in which the sentential is primary (for use in argument), and they involve reduction (and hence eliminability in a ground language).
     From: Anil Gupta (Definitions [2008], 2.2)
Traditional definitions need: same category, mention of the term, and conservativeness and eliminability [Gupta]
     Full Idea: A traditional definition requires that the definiendum contains the defined term, that definiendum and definiens are of the same logical category, and the definition is conservative (adding nothing new), and makes elimination possible.
     From: Anil Gupta (Definitions [2008], 2.4)
A definition can be 'extensionally', 'intensionally' or 'sense' adequate [Gupta]
     Full Idea: A definition is 'extensionally adequate' iff there are no actual counterexamples to it. It is 'intensionally adequate' iff there are no possible counterexamples to it. It is 'sense adequate' (or 'analytic') iff it endows the term with the right sense.
     From: Anil Gupta (Definitions [2008], 1.4)
2. Reason / D. Definition / 4. Real Definition
Chemists aim at real definition of things; lexicographers aim at nominal definition of usage [Gupta]
     Full Idea: The chemist aims at real definition, whereas the lexicographer aims at nominal definition. ...Perhaps real definitions investigate the thing denoted, and nominal definitions investigate meaning and use.
     From: Anil Gupta (Definitions [2008], 1.1)
     A reaction: Very helpful. I really think we should talk much more about the neglected chemists when we discuss science. Theirs is the single most successful branch of science, the paradigm case of what the whole enterprise aims at.
2. Reason / D. Definition / 6. Definition by Essence
If definitions aim at different ideals, then defining essence is not a unitary activity [Gupta]
     Full Idea: Some definitions aim at precision, others at fairness, or at accuracy, or at clarity, or at fecundity. But if definitions 'give the essence of things' (the Aristotelian formula), then it may not be a unitary kind of activity.
     From: Anil Gupta (Definitions [2008], 1)
     A reaction: We don't have to accept this conclusion so quickly. Human interests may shift the emphasis, but there may be a single ideal definition of which these various examples are mere parts.
2. Reason / D. Definition / 10. Stipulative Definition
Stipulative definition assigns meaning to a term, ignoring prior meanings [Gupta]
     Full Idea: Stipulative definition imparts a meaning to the defined term, and involves no commitment that the assigned meaning agrees with prior uses (if any) of the term
     From: Anil Gupta (Definitions [2008], 1.3)
     A reaction: A nice question is how far one can go in stretching received usage. If I define 'democracy' as 'everyone is involved in decisions', that is sort of right, but pushing the boundaries (children, criminals etc).
2. Reason / D. Definition / 11. Ostensive Definition
Ostensive definitions look simple, but are complex and barely explicable [Gupta]
     Full Idea: Ostensive definitions look simple (say 'this stick is one meter long', while showing a stick), but they are effective only because a complex linguistic and conceptual capacity is operative in the background, of which it is hard to give an account.
     From: Anil Gupta (Definitions [2008], 1.2)
     A reaction: The full horror of the situation is brought out in Quine's 'gavagai' example (Idea 6312)
4. Formal Logic / F. Set Theory ST / 6. Ordering in Sets
The ordered pair <x,y> is defined as the set {{x},{x,y}}, capturing function, not meaning [Gupta]
     Full Idea: The ordered pair <x,y> is defined as the set {{x},{x,y}}. This does captures its essential uses. Pairs <x,y> <u,v> are identical iff x=u and y=v, and the definition satisfies this. Function matters here, not meaning.
     From: Anil Gupta (Definitions [2008], 1.5)
     A reaction: This is offered as an example of Carnap's 'explications', rather than pure definitions. Quine extols it as a philosophical paradigm (1960:§53).
9. Objects / A. Existence of Objects / 2. Abstract Objects / d. Problems with abstracta
How we refer to abstractions is much less clear than how we refer to other things [Rosen]
     Full Idea: It is unclear how we manage to refer determinately to abstract entities in a sense in which it is not unclear how we manage to refer determinately to other things.
     From: Gideon Rosen (Abstract Objects [2001], 'Way of Ex')
     A reaction: This is where problems of abstraction overlap with problems about reference in language. Can we have a 'baptism' account of each abstraction (even very large numbers)? Will descriptions do it? Do abstractions collapse into particulars when we refer?
9. Objects / A. Existence of Objects / 5. Individuation / e. Individuation by kind
'Ultimate sortals' cannot explain ontological categories [Westerhoff on Wiggins]
     Full Idea: 'Ultimate sortals' are said to be non-subordinated, disjoint from one another, and uniquely paired with each object. Because of this, the ultimate sortal cannot be a satisfactory explication of the notion of an ontological category.
     From: comment on David Wiggins (Identity and Spatio-Temporal Continuity [1971], p.75) by Jan Westerhoff - Ontological Categories §26
     A reaction: My strong intuitions are that Wiggins is plain wrong, and Westerhoff gives the most promising reasons for my intuition. The simplest point is that objects can obviously belong to more than one category.
18. Thought / E. Abstraction / 2. Abstracta by Selection
The Way of Abstraction used to say an abstraction is an idea that was formed by abstracting [Rosen]
     Full Idea: The simplest version of the Way of Abstraction would be to say that an object is abstract if it is a referent of an idea that was formed by abstraction, but this is wedded to an outmoded philosophy of mind.
     From: Gideon Rosen (Abstract Objects [2001], 'Way of Abs')
     A reaction: This presumably refers to Locke, who wields the highly ambiguous term 'idea'. But if we sort out that ambiguity (by using modern talk of mental events, concepts and content?) we might reclaim the view. But do we have a 'genetic fallacy' here?
18. Thought / E. Abstraction / 5. Abstracta by Negation
Nowadays abstractions are defined as non-spatial, causally inert things [Rosen]
     Full Idea: If any characterization of the abstract deserves to be regarded as the modern standard one, it is this: an abstract entity is a non-spatial (or non-spatiotemporal) causally inert thing. This view presents a number of perplexities...
     From: Gideon Rosen (Abstract Objects [2001], 'Non-spat')
     A reaction: As indicated in other ideas, the problem is that some abstractions do seem to be located somewhere in space-time, and to have come into existence, and to pass away. I like 'to exist is to have causal powers'. See Ideas 5992 and 8300.
Chess may be abstract, but it has existed in specific space and time [Rosen]
     Full Idea: The natural view of chess is not that it is a non-spatiotemporal mathematical object, but that it was invented at a certain time and place, that it has changed over the years, and so on.
     From: Gideon Rosen (Abstract Objects [2001], 'Non-spat')
     A reaction: This strikes me as being undeniable, and being an incredibly important point. Logicians seem to want to subsume things like games into the highly abstract world of logic and numbers. In fact the direction of explanation should be reversed.
Sets are said to be abstract and non-spatial, but a set of books can be on a shelf [Rosen]
     Full Idea: It is thought that sets are abstract, abstract objects do not exist in space, so sets must not exist in space. But it is not unnatural to say that a set of books is located on a certain shelf in the library.
     From: Gideon Rosen (Abstract Objects [2001], 'Non-spat')
     A reaction: The arguments against non-spatiality of abstractions seem to me to be conclusive. Not being able to assign a location to the cosine function is on a par with not knowing where my thoughts are located in my brain.
18. Thought / E. Abstraction / 6. Abstracta by Conflation
Conflating abstractions with either sets or universals is a big claim, needing a big defence [Rosen]
     Full Idea: The Way of Conflation account of abstractions (identifying them sets or with universals) is now relatively rare. The claim sets or universals are the only abstract objects would amount to a substantive metaphysical thesis, in need of defence.
     From: Gideon Rosen (Abstract Objects [2001], 'Way of Con')
     A reaction: If you produce a concept like 'mammal' by psychological abstraction, you do seem to end up with a set of things with shared properties, so this approach is not silly. I can't think of any examples of abstractions which are not sets or universals.
18. Thought / E. Abstraction / 7. Abstracta by Equivalence
Functional terms can pick out abstractions by asserting an equivalence relation [Rosen]
     Full Idea: On Frege's suggestion, functional terms that pick out abstract expressions (such as 'direction' or 'equinumeral') have a typical form of f(a) = f(b) iff aRb, where R is an equivalence relation, a relation which is reflexive, symmetric and transitive.
     From: Gideon Rosen (Abstract Objects [2001], 'Way of Abs')
     A reaction: [Wright and Hale are credited with the details] This has become the modern orthodoxy among the logically-minded. Examples of R are 'parallel' or 'just as many as'. It picks out an 'aspect', which isn't far from the old view.
Abstraction by equivalence relationships might prove that a train is an abstract entity [Rosen]
     Full Idea: It seems possible to define a train in terms of its carriages and the connection relationship, which would meet the equivalence account of abstraction, but demonstrate that trains are actually abstract.
     From: Gideon Rosen (Abstract Objects [2001], 'Way of Abs')
     A reaction: [Compressed. See article for more detail] A tricky example, but a suggestive line of criticism. If you find two physical objects which relate to one another reflexively, symmetrically and transitively, they may turn out to be abstract.