Combining Texts

All the ideas for 'fragments/reports', 'Mathematical Logic (revised)' and 'What Price Bivalence?'

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6 ideas

5. Theory of Logic / D. Assumptions for Logic / 1. Bivalence
Bivalence applies not just to sentences, but that general terms are true or false of each object [Quine]
     Full Idea: It is in the spirit of bivalence not just to treat each closed sentence as true or false; as Frege stressed, each general term must be definitely true or false of each object, specificiable or not.
     From: Willard Quine (What Price Bivalence? [1981], p.36)
     A reaction: But note that this is only the 'spirit' of the thing. If you had (as I do) doubts about whether predicates actually refer to genuine 'properties', you may want to stick to the whole sentence view, and not be so fine-grained.
5. Theory of Logic / E. Structures of Logic / 4. Variables in Logic
'Corner quotes' (quasi-quotation) designate 'whatever these terms designate' [Quine]
     Full Idea: A 'quasi-quotation' [corner quotes, Quine quotes] designates that (unspecified) expression which is obtained from the contents of the corners by replacing the Greek letters by the (unspecified) expressions which they designate.
     From: Willard Quine (Mathematical Logic (revised) [1940], 1.6)
     A reaction: Filed under 'variables', as they seem to be variables that can refer to actual expressions, like algebra. Quine was determined to distinguish clearly between 'mention' and 'use'. 'Half-hearted substitutional quantification', says Fine.
5. Theory of Logic / F. Referring in Logic / 1. Naming / f. Names eliminated
We might do without names, by converting them into predicates [Quine, by Kirkham]
     Full Idea: Quine suggests that we can have a language with just predicates and no names. Thus for 'Ralph is red' we say 'x Ralphises and x is red'.
     From: report of Willard Quine (Mathematical Logic (revised) [1940]) by Richard L. Kirkham - Theories of Truth: a Critical Introduction 5.6
     A reaction: Kirkham discusses this as a way of getting round the lack of names in Tarski's theory of truth (which just uses objects, predicates and quantifiers). Otherwise you must supplement Tarski with an account of what the names refer to.
7. Existence / D. Theories of Reality / 10. Vagueness / d. Vagueness as linguistic
Terms learned by ostension tend to be vague, because that must be quick and unrefined [Quine]
     Full Idea: A term is apt to be vague if it is to be learned by ostension, since its applicability must admit of being judged on the spot and so cannot hinge of fine distinctions laboriously drawn.
     From: Willard Quine (What Price Bivalence? [1981], p.32)
     A reaction: [Quine cites C. Wright for this] Presumably precision can steadily increased by repeated ostension. After the first 'dog' it's pretty vague; after hundreds of them we are pretty clear about it. Long observation of borderline 'clouds' could do the same.
26. Natural Theory / A. Speculations on Nature / 5. Infinite in Nature
Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius]
     Full Idea: Archelaus was the first person to say that the universe is boundless.
     From: report of Archelaus (fragments/reports [c.450 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 02.Ar.3
27. Natural Reality / G. Biology / 3. Evolution
Archelaus said life began in a primeval slime [Archelaus, by Schofield]
     Full Idea: Archelaus wrote that life on Earth began in a primeval slime.
     From: report of Archelaus (fragments/reports [c.450 BCE]) by Malcolm Schofield - Archelaus
     A reaction: This sounds like a fairly clearcut assertion of the production of life by evolution. Darwin's contribution was to propose the mechanism for achieving it. We should honour the name of Archelaus for this idea.