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All the ideas for 'fragments/reports', 'Problems of Knowledge' and 'Axiomatic Theories of Truth'

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77 ideas

1. Philosophy / D. Nature of Philosophy / 3. Philosophy Defined
Even pointing a finger should only be done for a reason [Epictetus]
1. Philosophy / F. Analytic Philosophy / 5. Linguistic Analysis
Analysis rests on natural language, but its ideal is a framework which revises language [Halbach]
2. Reason / D. Definition / 2. Aims of Definition
An explicit definition enables the elimination of what is defined [Halbach]
2. Reason / E. Argument / 3. Analogy
Don't trust analogies; they are no more than a guideline [Halbach]
3. Truth / A. Truth Problems / 1. Truth
Truth-value 'gluts' allow two truth values together; 'gaps' give a partial conception of truth [Halbach]
Truth axioms prove objects exist, so truth doesn't seem to be a logical notion [Halbach]
3. Truth / A. Truth Problems / 2. Defining Truth
Any definition of truth requires a metalanguage [Halbach]
Traditional definitions of truth often make it more obscure, rather than less [Halbach]
If people have big doubts about truth, a definition might give it more credibility [Halbach]
3. Truth / C. Correspondence Truth / 3. Correspondence Truth critique
The only way to specify the corresponding fact is asserting the sentence [Williams,M]
3. Truth / D. Coherence Truth / 1. Coherence Truth
Justification needs coherence, while truth might be ideal coherence [Williams,M]
Coherence needs positive links, not just absence of conflict [Williams,M]
3. Truth / F. Semantic Truth / 1. Tarski's Truth / c. Meta-language for truth
Semantic theories avoid Tarski's Theorem by sticking to a sublanguage [Halbach]
3. Truth / F. Semantic Truth / 2. Semantic Truth
Disquotational truth theories are short of deductive power [Halbach]
3. Truth / G. Axiomatic Truth / 1. Axiomatic Truth
CT proves PA consistent, which PA can't do on its own, so CT is not conservative over PA [Halbach]
Axiomatic truth doesn't presuppose a truth-definition, though it could admit it at a later stage [Halbach]
The main semantic theories of truth are Kripke's theory, and revisions semantics [Halbach]
To axiomatise Tarski's truth definition, we need a binary predicate for his 'satisfaction' [Halbach]
Compositional Truth CT has the truth of a sentence depending of the semantic values of its constituents [Halbach]
Gödel numbering means a theory of truth can use Peano Arithmetic as its base theory [Halbach]
Truth axioms need a base theory, because that is where truth issues arise [Halbach]
We know a complete axiomatisation of truth is not feasible [Halbach]
A theory is 'conservative' if it adds no new theorems to its base theory [Halbach, by PG]
The Tarski Biconditional theory TB is Peano Arithmetic, plus truth, plus all Tarski bi-conditionals [Halbach]
Theories of truth are 'typed' (truth can't apply to sentences containing 'true'), or 'type-free' [Halbach]
3. Truth / G. Axiomatic Truth / 2. FS Truth Axioms
Friedman-Sheard is type-free Compositional Truth, with two inference rules for truth [Halbach]
3. Truth / G. Axiomatic Truth / 3. KF Truth Axioms
Kripke-Feferman theory KF axiomatises Kripke fixed-points, with Strong Kleene logic with gluts [Halbach]
The KF theory is useful, but it is not a theory containing its own truth predicate [Halbach]
The KF is much stronger deductively than FS, which relies on classical truth [Halbach]
3. Truth / H. Deflationary Truth / 2. Deflationary Truth
Compositional Truth CT proves generalisations, so is preferred in discussions of deflationism [Halbach]
Some say deflationism is axioms which are conservative over the base theory [Halbach]
Deflationism says truth is a disquotation device to express generalisations, adding no new knowledge [Halbach]
The main problem for deflationists is they can express generalisations, but not prove them [Halbach]
Deflationists say truth is just for expressing infinite conjunctions or generalisations [Halbach]
4. Formal Logic / E. Nonclassical Logics / 3. Many-Valued Logic
In Strong Kleene logic a disjunction just needs one disjunct to be true [Halbach]
In Weak Kleene logic there are 'gaps', neither true nor false if one component lacks a truth value [Halbach]
4. Formal Logic / F. Set Theory ST / 1. Set Theory
Every attempt at formal rigour uses some set theory [Halbach]
5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
Deduction shows entailments, not what to believe [Williams,M]
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
The underestimated costs of giving up classical logic are found in mathematical reasoning [Halbach]
5. Theory of Logic / E. Structures of Logic / 8. Theories in Logic
A theory is some formulae and all of their consequences [Halbach]
5. Theory of Logic / K. Features of Logics / 3. Soundness
You cannot just say all of Peano arithmetic is true, as 'true' isn't part of the system [Halbach]
Normally we only endorse a theory if we believe it to be sound [Halbach]
Soundness must involve truth; the soundness of PA certainly needs it [Halbach]
5. Theory of Logic / L. Paradox / 1. Paradox
Many new paradoxes may await us when we study interactions between frameworks [Halbach]
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / a. The Liar paradox
The liar paradox applies truth to a negated truth (but the conditional will serve equally) [Halbach]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / d. Peano arithmetic
The compactness theorem can prove nonstandard models of PA [Halbach]
The global reflection principle seems to express the soundness of Peano Arithmetic [Halbach]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
To reduce PA to ZF, we represent the non-negative integers with von Neumann ordinals [Halbach]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / b. Type theory
Set theory was liberated early from types, and recent truth-theories are exploring type-free [Halbach]
7. Existence / C. Structure of Existence / 2. Reduction
That Peano arithmetic is interpretable in ZF set theory is taken by philosophers as a reduction [Halbach]
10. Modality / A. Necessity / 2. Nature of Necessity
Maybe necessity is a predicate, not the usual operator, to make it more like truth [Halbach]
11. Knowledge Aims / A. Knowledge / 4. Belief / a. Beliefs
We could never pin down how many beliefs we have [Williams,M]
11. Knowledge Aims / B. Certain Knowledge / 1. Certainty
Propositions make error possible, so basic experiential knowledge is impossible [Williams,M]
11. Knowledge Aims / C. Knowing Reality / 2. Phenomenalism
Phenomenalism is a form of idealism [Williams,M]
12. Knowledge Sources / B. Perception / 4. Sense Data / a. Sense-data theory
Sense data avoid the danger of misrepresenting the world [Williams,M]
12. Knowledge Sources / B. Perception / 4. Sense Data / d. Sense-data problems
Sense data can't give us knowledge if they are non-propositional [Williams,M]
13. Knowledge Criteria / A. Justification Problems / 1. Justification / a. Justification issues
Is it people who are justified, or propositions? [Williams,M]
13. Knowledge Criteria / B. Internal Justification / 2. Pragmatic justification
What works always takes precedence over theories [Williams,M]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / b. Basic beliefs
Experience must be meaningful to act as foundations [Williams,M]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / c. Empirical foundations
Are empirical foundations judgements or experiences? [Williams,M]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / f. Foundationalism critique
Foundationalists are torn between adequacy and security [Williams,M]
Strong justification eliminates error, but also reduces our true beliefs [Williams,M]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / c. Coherentism critique
Why should diverse parts of our knowledge be connected? [Williams,M]
Coherence theory must give a foundational status to coherence itself [Williams,M]
13. Knowledge Criteria / C. External Justification / 1. External Justification
Externalism does not require knowing that you know [Williams,M]
Externalism ignores the social aspect of knowledge [Williams,M]
13. Knowledge Criteria / C. External Justification / 2. Causal Justification
In the causal theory of knowledge the facts must cause the belief [Williams,M]
How could there be causal relations to mathematical facts? [Williams,M]
Only a belief can justify a belief [Williams,M]
13. Knowledge Criteria / C. External Justification / 3. Reliabilism / a. Reliable knowledge
Externalist reliability refers to a range of conventional conditions [Williams,M]
13. Knowledge Criteria / C. External Justification / 3. Reliabilism / b. Anti-reliabilism
Sometimes I ought to distrust sources which are actually reliable [Williams,M]
13. Knowledge Criteria / C. External Justification / 5. Controlling Beliefs
We control our beliefs by virtue of how we enquire [Williams,M]
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
Scepticism just reveals our limited ability to explain things [Williams,M]
13. Knowledge Criteria / D. Scepticism / 2. Types of Scepticism
Scepticism can involve discrepancy, relativity, infinity, assumption and circularity [Williams,M]
14. Science / A. Basis of Science / 1. Observation
Seeing electrons in a cloud chamber requires theory [Williams,M]
19. Language / A. Nature of Meaning / 7. Meaning Holism / a. Sentence meaning
Foundationalists base meaning in words, coherentists base it in sentences [Williams,M]
19. Language / D. Propositions / 4. Mental Propositions
We need propositions to ascribe the same beliefs to people with different languages [Halbach]