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All the ideas for 'Philosophical Logic', 'Aboutness' and 'Epistemology'

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48 ideas

3. Truth / A. Truth Problems / 5. Truth Bearers
A statement S is 'partly true' if it has some wholly true parts [Yablo]
4. Formal Logic / A. Syllogistic Logic / 2. Syllogistic Logic
An 'enthymeme' is an argument with an indispensable unstated assumption [Yablo]
4. Formal Logic / D. Modal Logic ML / 6. Temporal Logic
With four tense operators, all complex tenses reduce to fourteen basic cases [Burgess]
4. Formal Logic / D. Modal Logic ML / 7. Barcan Formula
The temporal Barcan formulas fix what exists, which seems absurd [Burgess]
4. Formal Logic / E. Nonclassical Logics / 2. Intuitionist Logic
Is classical logic a part of intuitionist logic, or vice versa? [Burgess]
It is still unsettled whether standard intuitionist logic is complete [Burgess]
4. Formal Logic / E. Nonclassical Logics / 5. Relevant Logic
Relevance logic's → is perhaps expressible by 'if A, then B, for that reason' [Burgess]
4. Formal Logic / G. Formal Mereology / 3. Axioms of Mereology
y is only a proper part of x if there is a z which 'makes up the difference' between them [Yablo]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
Technical people see logic as any formal system that can be studied, not a study of argument validity [Burgess]
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
Classical logic neglects the non-mathematical, such as temporality or modality [Burgess]
Classical logic neglects counterfactuals, temporality and modality, because maths doesn't use them [Burgess]
The Cut Rule expresses the classical idea that entailment is transitive [Burgess]
5. Theory of Logic / A. Overview of Logic / 9. Philosophical Logic
Philosophical logic is a branch of logic, and is now centred in computer science [Burgess]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
Formalising arguments favours lots of connectives; proving things favours having very few [Burgess]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / e. or
Asserting a disjunction from one disjunct seems odd, but can be sensible, and needed in maths [Burgess]
5. Theory of Logic / E. Structures of Logic / 4. Variables in Logic
All occurrences of variables in atomic formulas are free [Burgess]
5. Theory of Logic / F. Referring in Logic / 1. Naming / e. Empty names
'Pegasus doesn't exist' is false without Pegasus, yet the absence of Pegasus is its truthmaker [Yablo]
5. Theory of Logic / F. Referring in Logic / 2. Descriptions / b. Definite descriptions
The denotation of a definite description is flexible, rather than rigid [Burgess]
5. Theory of Logic / H. Proof Systems / 1. Proof Systems
'Induction' and 'recursion' on complexity prove by connecting a formula to its atomic components [Burgess]
5. Theory of Logic / H. Proof Systems / 6. Sequent Calculi
The sequent calculus makes it possible to have proof without transitivity of entailment [Burgess]
We can build one expanding sequence, instead of a chain of deductions [Burgess]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
'Tautologies' are valid formulas of classical sentential logic - or substitution instances in other logics [Burgess]
5. Theory of Logic / I. Semantics of Logic / 4. Satisfaction
Validity (for truth) and demonstrability (for proof) have correlates in satisfiability and consistency [Burgess]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
We only need to study mathematical models, since all other models are isomorphic to these [Burgess]
Models leave out meaning, and just focus on truth values [Burgess]
We aim to get the technical notion of truth in all models matching intuitive truth in all instances [Burgess]
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / a. The Liar paradox
The Liar seems like a truth-value 'gap', but dialethists see it as a 'glut' [Burgess]
6. Mathematics / C. Sources of Mathematics / 3. Mathematical Nominalism
A nominalist can assert statements about mathematical objects, as being partly true [Yablo]
9. Objects / C. Structure of Objects / 8. Parts of Objects / a. Parts of objects
Parthood lacks the restriction of kind which most relations have [Yablo]
10. Modality / A. Necessity / 4. De re / De dicto modality
De re modality seems to apply to objects a concept intended for sentences [Burgess]
10. Modality / A. Necessity / 6. Logical Necessity
Logical necessity has two sides - validity and demonstrability - which coincide in classical logic [Burgess]
General consensus is S5 for logical modality of validity, and S4 for proof [Burgess]
10. Modality / B. Possibility / 8. Conditionals / a. Conditionals
It is doubtful whether the negation of a conditional has any clear meaning [Burgess]
Three conditionals theories: Materialism (material conditional), Idealism (true=assertable), Nihilism (no truth) [Burgess]
11. Knowledge Aims / C. Knowing Reality / 2. Phenomenalism
The phenomenalist says that to be is to be perceivable [Cardinal/Hayward/Jones]
Linguistic phenomenalism says we can eliminate talk of physical objects [Cardinal/Hayward/Jones]
If we lack enough sense-data, are we to say that parts of reality are 'indeterminate'? [Cardinal/Hayward/Jones]
12. Knowledge Sources / B. Perception / 2. Qualities in Perception / c. Primary qualities
Primary qualities can be described mathematically, unlike secondary qualities [Cardinal/Hayward/Jones]
An object cannot remain an object without its primary qualities [Cardinal/Hayward/Jones]
13. Knowledge Criteria / A. Justification Problems / 2. Justification Challenges / b. Gettier problem
Gettier says you don't know if you are confused about how it is true [Yablo]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / c. Coherentism critique
My justifications might be very coherent, but totally unconnected to the world [Cardinal/Hayward/Jones]
14. Science / B. Scientific Theories / 2. Aim of Science
A theory need not be true to be good; it should just be true about its physical aspects [Yablo]
14. Science / C. Induction / 5. Paradoxes of Induction / b. Raven paradox
If sentences point to different evidence, they must have different subject-matter [Yablo]
Most people say nonblack nonravens do confirm 'all ravens are black', but only a tiny bit [Yablo]
19. Language / A. Nature of Meaning / 4. Meaning as Truth-Conditions
Sentence-meaning is the truth-conditions - plus factors responsible for them [Yablo]
19. Language / C. Assigning Meanings / 4. Compositionality
The content of an assertion can be quite different from compositional content [Yablo]
19. Language / C. Assigning Meanings / 6. Truth-Conditions Semantics
Truth-conditions as subject-matter has problems of relevance, short cut, and reversal [Yablo]
19. Language / F. Communication / 3. Denial
Not-A is too strong to just erase an improper assertion, because it actually reverses A [Yablo]