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All the ideas for 'Intensional Logic', 'works' and 'Our Knowledge of Mathematical Objects'

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21 ideas

1. Philosophy / E. Nature of Metaphysics / 3. Metaphysical Systems
Super-ordinate disciplines give laws or principles; subordinate disciplines give concrete cases [Peirce, by Atkin]
     Full Idea: In Peirce's system, a super-ordinate discipline provides general laws or principles for subordinate disciplines, which in turn provide concrete examples of those general laws.
     From: report of Charles Sanders Peirce (works [1892]) by Albert Atkin - Peirce 1 'System'
     A reaction: Does he really mean that subordinate disciplines have no principles or laws? That can't be right.
3. Truth / E. Pragmatic Truth / 1. Pragmatic Truth
Pragmatic 'truth' is a term to cover the many varied aims of enquiry [Peirce, by Misak]
     Full Idea: In Peirce's naturalist view of truth, it is a catch-all for the particular local aims of enquiry - empirical adequacy, predictive power, coherence, simplicity, elegance, explanatory power, a reliable guide to action, fruitfulness, great understanding.
     From: report of Charles Sanders Peirce (works [1892]) by Cheryl Misak - Pragmatism and Deflationism 1
     A reaction: The aims I cited in my thesis on explanation. One given, for me, is that truth is an ideal, which may or may not be attainable, to varying degrees. It is just what thinking aims at. I suspect, though, that these listed items have one thing in common.
Peirce did not think a belief was true if it was useful [Peirce, by Misak]
     Full Idea: Peirce was not in the slightest bit tempted by the thought that a belief is true if it is useful.
     From: report of Charles Sanders Peirce (works [1892]) by Cheryl Misak - Pragmatism and Deflationism 2
     A reaction: All students of the pragmatic theory of truth should start with this idea, because it rejects the caricature view of pragmatic truth, a view which is easily rebutted. James seems to have been guilty of this sin.
If truth is the end of enquiry, what if it never ends, or ends prematurely? [Atkin on Peirce]
     Full Idea: Two related worries about Peirce's account of truth are (from Royce) what are we to make of truth if enquiry never reaches an end, and (from Russell) what are we to make of truth if enquiry ends prematurely?
     From: comment on Charles Sanders Peirce (works [1892]) by Albert Atkin - Peirce 3 'issues'
     A reaction: The defence of Peirce must be that the theory is not holistic - referring to the whole Truth about absolutely everything. The discovery of the periodic table seems to me to support Peirce. In many areas basic enquiry has reached an end.
4. Formal Logic / E. Nonclassical Logics / 8. Intensional Logic
If terms change their designations in different states, they are functions from states to objects [Fitting]
     Full Idea: The common feature of every designating term is that designation may change from state to state - thus it can be formalized by a function from states to objects.
     From: Melvin Fitting (Intensional Logic [2007], 3)
     A reaction: Specifying the objects sounds OK, but specifying states sounds rather tough.
Intensional logic adds a second type of quantification, over intensional objects, or individual concepts [Fitting]
     Full Idea: To first order modal logic (with quantification over objects) we can add a second kind of quantification, over intensions. An intensional object, or individual concept, will be modelled by a function from states to objects.
     From: Melvin Fitting (Intensional Logic [2007], 3.3)
4. Formal Logic / E. Nonclassical Logics / 9. Awareness Logic
Awareness logic adds the restriction of an awareness function to epistemic logic [Fitting]
     Full Idea: Awareness logic enriched Hintikka's epistemic models with an awareness function, mapping each state to the set of formulas we are aware of at that state. This reflects some bound on the resources we can bring to bear.
     From: Melvin Fitting (Intensional Logic [2007], 3.6.1)
     A reaction: [He cites Fagin and Halpern 1988 for this]
4. Formal Logic / E. Nonclassical Logics / 10. Justification Logics
Justication logics make explicit the reasons for mathematical truth in proofs [Fitting]
     Full Idea: In justification logics, the logics of knowledge are extended by making reasons explicit. A logic of proof terms was created, with a semantics. In this, mathematical truths are known for explicit reasons, and these provide a measure of complexity.
     From: Melvin Fitting (Intensional Logic [2007], 3.6.1)
5. Theory of Logic / A. Overview of Logic / 8. Logic of Mathematics
Classical logic is deliberately extensional, in order to model mathematics [Fitting]
     Full Idea: Mathematics is typically extensional throughout (we write 3+2=2+3 despite the two terms having different meanings). ..Classical first-order logic is extensional by design since it primarily evolved to model the reasoning of mathematics.
     From: Melvin Fitting (Intensional Logic [2007], §1)
5. Theory of Logic / C. Ontology of Logic / 3. If-Thenism
Pure mathematics deals only with hypotheses, of which the reality does not matter [Peirce]
     Full Idea: The pure mathematician deals exclusively with hypotheses. Whether or not there is any corresponding real thing, he does not care.
     From: Charles Sanders Peirce (works [1892], CP5.567), quoted by Albert Atkin - Peirce 3 'separation'
     A reaction: [Dated 1902] Maybe we should identify a huge branch of human learning as Hyptheticals. Professor of Hypotheticals at Cambridge University. The trouble is it would have to include computer games. So why does maths matter more than games?
5. Theory of Logic / D. Assumptions for Logic / 1. Bivalence
Bivalence is a regulative assumption of enquiry - not a law of logic [Peirce, by Misak]
     Full Idea: Peirce takes bivalence not to be a law of logic, but a regulative assumption of enquiry.
     From: report of Charles Sanders Peirce (works [1892]) by Cheryl Misak - Pragmatism and Deflationism 2 n10
     A reaction: I like this. For most enquiries it's either true or not true, it's either there or it's not there. When you aren't faced with these simple dichotomies (in history, or quantum mechanics) you can relax, and allow truth value gaps etc.
5. Theory of Logic / F. Referring in Logic / 3. Property (λ-) Abstraction
λ-abstraction disambiguates the scope of modal operators [Fitting]
     Full Idea: λ-abstraction can be used to abstract and disambiguate a predicate. De re is [λx◊P(x)](f) - f has the possible-P property - and de dicto is ◊[λxP(x)](f) - possibly f has the P-property. Also applies to □.
     From: Melvin Fitting (Intensional Logic [2007], §3.3)
     A reaction: Compare the Barcan formula. Originated with Church in the 1930s, and Carnap 1947, but revived by Stalnaker and Thomason 1968. Because it refers to the predicate, it has a role in intensional versions of logic, especially modal logic.
6. Mathematics / C. Sources of Mathematics / 6. Logicism / c. Neo-logicism
Proceduralism offers a version of logicism with no axioms, or objects, or ontological commitment [Fine,K]
     Full Idea: My Proceduralism offers axiom-free foundations for mathematics. Axioms give way to the stipulation of procedures. We obtain a form of logicism, but with a procedural twist, and with a logic which is ontologically neutral, and no assumption of objects.
     From: Kit Fine (Our Knowledge of Mathematical Objects [2005], 1)
     A reaction: [See Ideas 9222 and 9223 for his Proceduralism] Sounds like philosophical heaven. We get to take charge of mathematics, without the embarrassment of declaring ourselves to be platonists. Someone, not me, should evaluate this.
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / a. Constructivism
The objects and truths of mathematics are imperative procedures for their construction [Fine,K]
     Full Idea: I call my new approach to mathematics 'proceduralism'. It agrees with Hilbert and Poincaré that the objects and truths are postulations, but takes them to be imperatival rather than indicative in form; not propositions, but procedures for construction.
     From: Kit Fine (Our Knowledge of Mathematical Objects [2005], Intro)
     A reaction: I'm not sure how an object or a truth can be a procedure, any more than a house can be a procedure. If a procedure doesn't have a product then it is an idle way to pass the time. The view seems to be related to fictionalism.
My Proceduralism has one simple rule, and four complex rules [Fine,K]
     Full Idea: My Proceduralism has one simple rule (introduce an object), and four complex rules: Composition (combining two procedures), Conditionality (if A, do B), Universality (do a procedure for every x), and Iteration (rule to keep doing B).
     From: Kit Fine (Our Knowledge of Mathematical Objects [2005], 1)
     A reaction: It sounds like a highly artificial and private game which Fine has invented, but he claims that this is the sort of thing that practising mathematicians have always done.
7. Existence / D. Theories of Reality / 3. Reality
The real is the idea in which the community ultimately settles down [Peirce]
     Full Idea: The real is the idea in which the community ultimately settles down.
     From: Charles Sanders Peirce (works [1892]), quoted by Martin Kusch - Knowledge by Agreement Ch.16
     A reaction: If this is anti-realism, then I don't like it. If it is realist, then it is probably a bit on the optimistic side (if you think about cultures that are into witchcraft and voodoo).
8. Modes of Existence / A. Relations / 1. Nature of Relations
Peirce and others began the mapping out of relations [Peirce, by Hart,WD]
     Full Idea: It was Peirce and Schröder in the nineteenth century who began a systematic taxonomy of relations.
     From: report of Charles Sanders Peirce (works [1892], 4) by William D. Hart - The Evolution of Logic 4
8. Modes of Existence / C. Powers and Dispositions / 6. Dispositions / d. Dispositions as occurrent
Peirce's later realism about possibilities and generalities went beyond logical positivism [Peirce, by Atkin]
     Full Idea: The realism about possibilities, generalities, tendencies and habits that we find in Peirce's later maxim is something that the logical positivists would have been uncomfortable with.
     From: report of Charles Sanders Peirce (works [1892]) by Albert Atkin - Peirce 2 'Concl'
     A reaction: Atkin examines the various later statements of the earlier maxim, given here in Idea 21490. Ryle and Quine express the empiricist and logical positivist approach to dispositions.
10. Modality / E. Possible worlds / 1. Possible Worlds / d. Possible worlds actualism
The possible can only be general, and the force of actuality is needed to produce a particular [Peirce]
     Full Idea: The possible is necessarily general…..It is only actuality, the force of existence, which bursts the fluidity of the general and produces a discrete unit.
     From: Charles Sanders Peirce (works [1892]), quoted by François Recanati - Mental Files 13.1
     A reaction: [Papers 4 1967:147] This was quoted by Prior, and is often cited. Recanati is interested in the notion of a singular thought being tied to actuality, by generating a mental file.
10. Modality / E. Possible worlds / 3. Transworld Objects / a. Transworld identity
Definite descriptions pick out different objects in different possible worlds [Fitting]
     Full Idea: Definite descriptions pick out different objects in different possible worlds quite naturally.
     From: Melvin Fitting (Intensional Logic [2007], 3.4)
     A reaction: A definite description can pick out the same object in another possible world, or a very similar one, or an object which has almost nothing in common with the others.
11. Knowledge Aims / B. Certain Knowledge / 3. Fallibilism
Inquiry is not standing on bedrock facts, but standing in hope on a shifting bog [Peirce]
     Full Idea: Inquiry is not standing upon a bedrock of fact. It is walking up a bog, and can only say, this ground seems to hold for the present. Here I will stay until it begins to give way.
     From: Charles Sanders Peirce (works [1892], CP 5.589), quoted by Gottfried Leibniz - Letter to Newton 4
     A reaction: [I don't know which article this lovely quote comes from]