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All the ideas for 'fragments/reports', 'Vagueness, Truth and Logic' and 'Logicism and Ontological Commits. of Arithmetic'

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23 ideas

1. Philosophy / F. Analytic Philosophy / 6. Logical Analysis
Study vagueness first by its logic, then by its truth-conditions, and then its metaphysics [Fine,K]
     Full Idea: My investigation of vagueness began with the question 'What is the correct logic of vagueness?', which led to the further question 'What are the correct truth-conditions for a vague language?', which led to questions of meaning and existence.
     From: Kit Fine (Vagueness, Truth and Logic [1975], Intro)
     A reaction: This is the most perfect embodiment of the strategy of analytical philosophy which I have ever read. It is the strategy invented by Frege in the 'Grundlagen'. Is this still the way to go, or has this pathway slowly sunk into the swamp?
3. Truth / F. Semantic Truth / 2. Semantic Truth
Truth in a model is more tractable than the general notion of truth [Hodes]
     Full Idea: Truth in a model is interesting because it provides a transparent and mathematically tractable model - in the 'ordinary' rather than formal sense of the term 'model' - of the less tractable notion of truth.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984], p.131)
     A reaction: This is an important warning to those who wish to build their entire account of truth on Tarski's rigorously formal account of the term. Personally I think we should start by deciding whether 'true' can refer to the mental state of a dog. I say it can.
Truth is quite different in interpreted set theory and in the skeleton of its language [Hodes]
     Full Idea: There is an enormous difference between the truth of sentences in the interpreted language of set theory and truth in some model for the disinterpreted skeleton of that language.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984], p.132)
     A reaction: This is a warning to me, because I thought truth and semantics only entered theories at the stage of 'interpretation'. I must go back and get the hang of 'skeletal' truth, which sounds rather charming. [He refers to set theory, not to logic.]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Higher-order logic may be unintelligible, but it isn't set theory [Hodes]
     Full Idea: Brand higher-order logic as unintelligible if you will, but don't conflate it with set theory.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984], p.131)
     A reaction: [he gives Boolos 1975 as a further reference] This is simply a corrective, because the conflation of second-order logic with set theory is an idea floating around in the literature.
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
Excluded Middle, and classical logic, may fail for vague predicates [Fine,K]
     Full Idea: Maybe classical logic fails for vagueness in Excluded Middle. If 'H bald ∨ ¬(H bald)' is true, then one disjunct is true. But if the second is true the first is false, and the sentence is either true or false, contrary to the borderline assumption.
     From: Kit Fine (Vagueness, Truth and Logic [1975], 4)
     A reaction: Fine goes on to argue against the implication that we need a special logic for vague predicates.
5. Theory of Logic / D. Assumptions for Logic / 4. Identity in Logic
Identity is a level one relation with a second-order definition [Hodes]
     Full Idea: Identity should he considered a logical notion only because it is the tip of a second-order iceberg - a level 1 relation with a pure second-order definition.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984])
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
When an 'interpretation' creates a model based on truth, this doesn't include Fregean 'sense' [Hodes]
     Full Idea: A model is created when a language is 'interpreted', by assigning non-logical terms to objects in a set, according to a 'true-in' relation, but we must bear in mind that this 'interpretation' does not associate anything like Fregean senses with terms.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984], p.131)
     A reaction: This seems like a key point (also made by Hofweber) that formal accounts of numbers, as required by logic, will not give an adequate account of the semantics of number-terms in natural languages.
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
Logic holding between indefinite sentences is the core of all language [Fine,K]
     Full Idea: If language is like a tree, then penumbral connection (logic holding among indefinite sentences) is the seed from which the tree grows, for it provides an initial repository of truths that are to be retained throughout all growth.
     From: Kit Fine (Vagueness, Truth and Logic [1975], 2)
     A reaction: A nice incidental insight arising from his investigation of vagueness. People accept one another's reasons even when they are confused, or hopeless at expressing themselves. Nice.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / a. Numbers
Mathematics is higher-order modal logic [Hodes]
     Full Idea: I take the view that (agreeing with Aristotle) mathematics only requires the notion of a potential infinity, ...and that mathematics is higher-order modal logic.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984])
     A reaction: Modern 'modal' accounts of mathematics I take to be heirs of 'if-thenism', which seems to have been Russell's development of Frege's original logicism. I'm beginning to think it is right. But what is the subject-matter of arithmetic?
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / f. Arithmetic
Arithmetic must allow for the possibility of only a finite total of objects [Hodes]
     Full Idea: Arithmetic should be able to face boldly the dreadful chance that in the actual world there are only finitely many objects.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984], p.148)
     A reaction: This seems to be a basic requirement for any account of arithmetic, but it was famously a difficulty for early logicism, evaded by making the existence of an infinity of objects into an axiom of the system.
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / a. For mathematical platonism
It is claimed that numbers are objects which essentially represent cardinality quantifiers [Hodes]
     Full Idea: The mathematical object-theorist says a number is an object that represents a cardinality quantifier, with the representation relation as the entire essence of the nature of such objects as cardinal numbers like 4.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984])
     A reaction: [compressed] This a classic case of a theory beginning to look dubious once you spell it our precisely. The obvious thought is to make do with the numerical quantifiers, and dispense with the objects. Do other quantifiers need objects to support them?
Numerical terms can't really stand for quantifiers, because that would make them first-level [Hodes]
     Full Idea: The dogmatic Frege is more right than wrong in denying that numerical terms can stand for numerical quantifiers, for there cannot be a language in which object-quantifiers and objects are simultaneously viewed as level zero.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984], p.142)
     A reaction: Subtle. We see why Frege goes on to say that numbers are level zero (i.e. they are objects). We are free, it seems, to rewrite sentences containing number terms to suit whatever logical form appeals. Numbers are just quantifiers?
7. Existence / D. Theories of Reality / 7. Fictionalism
Talk of mirror images is 'encoded fictions' about real facts [Hodes]
     Full Idea: Talk about mirror images is a sort of fictional discourse. Statements 'about' such fictions are not made true or false by our whims; rather they 'encode' facts about the things reflected in mirrors.
     From: Harold Hodes (Logicism and Ontological Commits. of Arithmetic [1984], p.146)
     A reaction: Hodes's proposal for how we should view abstract objects (c.f. Frege and Dummett on 'the equator'). The facts involved are concrete, but Hodes is offering 'encoding fictionalism' as a linguistic account of such abstractions. He applies it to numbers.
7. Existence / D. Theories of Reality / 10. Vagueness / d. Vagueness as linguistic
Vagueness is semantic, a deficiency of meaning [Fine,K]
     Full Idea: I take vagueness to be a semantic feature, a deficiency of meaning. It is to be distinguished from generality, undecidability, and ambiguity.
     From: Kit Fine (Vagueness, Truth and Logic [1975], Intro)
     A reaction: Sounds good. If we cut nature at the joints with our language, then nature is going to be too subtle and vast for our finite and gerrymandered language, and so it will break down in tricky situations. But maybe epistemology precedes semantics?
7. Existence / D. Theories of Reality / 10. Vagueness / e. Higher-order vagueness
A thing might be vaguely vague, giving us higher-order vagueness [Fine,K]
     Full Idea: There is a possibility of 'higher-order vagueness'. The vague may be vague, or vaguely vague, and so on. If J has few hairs on his head than H, then he may be a borderline case of a borderline case.
     From: Kit Fine (Vagueness, Truth and Logic [1975], 5)
     A reaction: Such slim grey areas can also be characterised as those where you think he is definitely bald, but I am not so sure.
7. Existence / D. Theories of Reality / 10. Vagueness / f. Supervaluation for vagueness
A vague sentence is only true for all ways of making it completely precise [Fine,K]
     Full Idea: A vague sentence is (roughly stated) true if and only if it is true for all ways of making it completely precise (the 'super-truth theory').
     From: Kit Fine (Vagueness, Truth and Logic [1975], Intro)
     A reaction: Intuitively this sounds quite promising. Personally I think we should focus on the 'proposition' rather than the 'sentence' (where fifteen sentences might be needed before we can agree on the one proposition).
Logical connectives cease to be truth-functional if vagueness is treated with three values [Fine,K]
     Full Idea: With a three-value approach, if P is 'blob is pink' and R is 'blob is red', then P&P is indefinite, but P&R is false, and P∨P is indefinite, but P∨R is true. This means the connectives & and ∨ are not truth-functional.
     From: Kit Fine (Vagueness, Truth and Logic [1975], 1)
     A reaction: The point is that there could then be no logic in any way classical for vague sentences and three truth values. A powerful point.
Meaning is both actual (determining instances) and potential (possibility of greater precision) [Fine,K]
     Full Idea: The meaning of an expression is the product of both its actual meaning (what helps determine its instances and counter-instances), and its potential meaning (the possibilities for making it more precise).
     From: Kit Fine (Vagueness, Truth and Logic [1975], 2)
     A reaction: A modal approach to meaning is gloriously original. Being quite a fan of real modalities (the possibilities latent in actuality), I find this intuitively appealing.
With the super-truth approach, the classical connectives continue to work [Fine,K]
     Full Idea: With the super-truth approach, if P is 'blob is pink' and R is 'blob is red', then P&R is false, and P∨R is true, since one of P and R is true and one is false in any complete and admissible specification. It encompasses all 'penumbral truths'.
     From: Kit Fine (Vagueness, Truth and Logic [1975], 3)
     A reaction: [See Idea 9767 for the super-truth approach, and Idea 9770 for a contrasting view] The approach, which seems quite appealing, is that we will in no circumstances give up basic classical logic, but we will make maximum concessions to vagueness.
Borderline cases must be under our control, as capable of greater precision [Fine,K]
     Full Idea: Any borderline case must be under our control, in the sense that it can be settled by making the predicates more precise.
     From: Kit Fine (Vagueness, Truth and Logic [1975], 3)
     A reaction: Sounds good. Consider an abstract concept like the equator. It is precise on a map of the world, but vague when you are in the middle of the tropics. But we can always form a committee to draw a (widish) line on the ground delineating it.
9. Objects / B. Unity of Objects / 3. Unity Problems / e. Vague objects
Vagueness can be in predicates, names or quantifiers [Fine,K]
     Full Idea: There are three possible sources of vagueness: the predicates, the names, and the quantifiers.
     From: Kit Fine (Vagueness, Truth and Logic [1975], 1)
     A reaction: Presumably a vagueness about the domain of discussion would be a vagueness in the quantifier. This is a helpful preliminary division, in the semantic approach to vagueness.
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.