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All the ideas for 'fragments/reports', 'Vagueness' and 'Is Hume's Principle analytic?'

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5 ideas

5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
Logical connectives have the highest precision, yet are infected by the vagueness of true and false [Russell, by Williamson]
     Full Idea: Russell says the best chance of avoiding vagueness are the logical connectives. ...But the vagueness of 'true' and 'false' infects the logical connectives too. All words are vague. Russell concludes that all language is vague.
     From: report of Bertrand Russell (Vagueness [1923]) by Timothy Williamson - Vagueness 2.4
     A reaction: This relies on the logical connectives being defined semantically, in terms of T and F, but that is standard. Presumably the formal uninterpreted syntax is not vague.
7. Existence / D. Theories of Reality / 10. Vagueness / d. Vagueness as linguistic
Since natural language is not precise it cannot be in the province of logic [Russell, by Keefe/Smith]
     Full Idea: Russell takes it that logic assumes precision, and since natural language is not precise it cannot be in the province of logic at all.
     From: report of Bertrand Russell (Vagueness [1923]) by R Keefe / P Smith - Intro: Theories of Vagueness §1
     A reaction: I find this view congenial. It seems to me that the necessary prelude to logic is to do everything you can to eliminate ambiguity and vagueness from the sentences at issue. We want the proposition, or logical form. If there isn't one, forget it?
Vagueness is only a characteristic of representations, such as language [Russell]
     Full Idea: Vagueness and precision alike are characteristics which can only belong to a representation, of which language is an example.
     From: Bertrand Russell (Vagueness [1923], p.62)
     A reaction: Russell was the first to tackle the question of vagueness, and he may have got it right. If we are unable to decide which set an object belongs in (red or orange) that is a problem for our conceptual/linguistic scheme. The object still has a colour!
18. Thought / E. Abstraction / 7. Abstracta by Equivalence
An 'abstraction principle' says two things are identical if they are 'equivalent' in some respect [Boolos]
     Full Idea: Hume's Principle has a structure Boolos calls an 'abstraction principle'. Within the scope of two universal quantifiers, a biconditional connects an identity between two things and an equivalence relation. It says we don't care about other differences.
     From: George Boolos (Is Hume's Principle analytic? [1997]), quoted by Michèle Friend - Introducing the Philosophy of Mathematics 3.7
     A reaction: This seems to be the traditional principle of abstraction by ignoring some properties, but dressed up in the clothes of formal logic. Frege tries to eliminate psychology, but Boolos implies that what we 'care about' is relevant.
21. Aesthetics / C. Artistic Issues / 7. Art and Morality
Musical performance can reveal a range of virtues [Damon of Ath.]
     Full Idea: In singing and playing the lyre, a boy will be likely to reveal not only courage and moderation, but also justice.
     From: Damon (fragments/reports [c.460 BCE], B4), quoted by (who?) - where?