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All the ideas for 'fragments/reports', 'Contemporary theories of Knowledge (2nd)' and 'Axiomatic Theories of Truth'

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70 ideas

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 axioms prove objects exist, so truth doesn't seem to be a logical notion [Halbach]
Truth-value 'gluts' allow two truth values together; 'gaps' give a partial conception of truth [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 / 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
Axiomatic truth doesn't presuppose a truth-definition, though it could admit it at a later stage [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]
The main semantic theories of truth are Kripke's theory, and revisions semantics [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]
CT proves PA consistent, which PA can't do on its own, so CT is not conservative over PA [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
The KF theory is useful, but it is not a theory containing its own truth predicate [Halbach]
Kripke-Feferman theory KF axiomatises Kripke fixed-points, with Strong Kleene logic with gluts [Halbach]
The KF is much stronger deductively than FS, which relies on classical truth [Halbach]
3. Truth / H. Deflationary Truth / 2. Deflationary Truth
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]
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]
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 / 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
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]
You cannot just say all of Peano arithmetic is true, as 'true' isn't part of the system [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 / 1. Knowledge
The main epistemological theories are foundationalist, coherence, probabilistic and reliabilist [Pollock/Cruz]
11. Knowledge Aims / B. Certain Knowledge / 1. Certainty
Most people now agree that our reasoning proceeds defeasibly, rather than deductively [Pollock/Cruz]
To believe maximum truths, believe everything; to have infallible beliefs, believe nothing [Pollock/Cruz]
11. Knowledge Aims / C. Knowing Reality / 1. Perceptual Realism / b. Direct realism
Direct realism says justification is partly a function of pure perceptual states, not of beliefs [Pollock/Cruz]
11. Knowledge Aims / C. Knowing Reality / 2. Phenomenalism
Phenomenalism offered conclusive perceptual knowledge, but conclusive reasons no longer seem essential [Pollock/Cruz]
12. Knowledge Sources / B. Perception / 1. Perception
Perception causes beliefs in us, without inference or justification [Pollock/Cruz]
12. Knowledge Sources / B. Perception / 6. Inference in Perception
Sense evidence is not beliefs, because they are about objective properties, not about appearances [Pollock/Cruz]
13. Knowledge Criteria / A. Justification Problems / 1. Justification / a. Justification issues
Bayesian epistemology is Bayes' Theorem plus the 'simple rule' (believe P if it is probable) [Pollock/Cruz]
13. Knowledge Criteria / A. Justification Problems / 3. Internal or External / a. Pro-internalism
Internalism says if anything external varies, the justifiability of the belief does not vary [Pollock/Cruz]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / b. Basic beliefs
People rarely have any basic beliefs, and never enough for good foundations [Pollock/Cruz]
Foundationalism requires self-justification, not incorrigibility [Pollock/Cruz]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / d. Rational foundations
Reason cannot be an ultimate foundation, because rational justification requires prior beliefs [Pollock/Cruz]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / f. Foundationalism critique
Foundationalism is wrong, because either all beliefs are prima facie justified, or none are [Pollock/Cruz]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / a. Coherence as justification
Negative coherence theories do not require reasons, so have no regress problem [Pollock/Cruz]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / c. Coherentism critique
Coherence theories fail, because they can't accommodate perception as the basis of knowledge [Pollock/Cruz]
Coherence theories isolate justification from the world [Pollock/Cruz]
13. Knowledge Criteria / C. External Justification / 1. External Justification
Externalism comes as 'probabilism' (probability of truth) and 'reliabilism' (probability of good cognitive process) [Pollock/Cruz]
13. Knowledge Criteria / C. External Justification / 2. Causal Justification
One belief may cause another, without being the basis for the second belief [Pollock/Cruz]
13. Knowledge Criteria / D. Scepticism / 6. Scepticism Critique
We can't start our beliefs from scratch, because we wouldn't know where to start [Pollock/Cruz]
14. Science / C. Induction / 1. Induction
Enumerative induction gives a universal judgement, while statistical induction gives a proportion [Pollock/Cruz]
14. Science / C. Induction / 6. Bayes's Theorem
Since every tautology has a probability of 1, should we believe all tautologies? [Pollock/Cruz]
14. Science / D. Explanation / 3. Best Explanation / a. Best explanation
Scientific confirmation is best viewed as inference to the best explanation [Pollock/Cruz]
19. Language / D. Propositions / 4. Mental Propositions
We need propositions to ascribe the same beliefs to people with different languages [Halbach]
22. Metaethics / C. The Good / 2. Happiness / b. Eudaimonia
Critolaus redefined Aristotle's moral aim as fulfilment instead of happiness [Critolaus, by White,SA]