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All the ideas for 'fragments/reports', 'talk' and 'Philosophical Logic'

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50 ideas

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]
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 / E. Structures of Logic / 5. Functions in Logic
F(x) walked into a bar. The barman said.. [Sommers,W]
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
We can build one expanding sequence, instead of a chain of deductions [Burgess]
The sequent calculus makes it possible to have proof without transitivity of entailment [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]
7. Existence / A. Nature of Existence / 3. Being / d. Non-being
Sartre to Waitress: Coffee with no cream, please... [Sommers,W]
7. Existence / D. Theories of Reality / 4. Anti-realism
Said Plato: 'The things that we feel... [Sommers,W]
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 / B. Certain Knowledge / 5. Cogito Critique
Barman to Descartes: Would you like another drink?... [Sommers,W]
There was a young student called Fred... [Sommers,W]
11. Knowledge Aims / C. Knowing Reality / 2. Phenomenalism
A philosopher and his wife are out for a drive... [Sommers,W]
11. Knowledge Aims / C. Knowing Reality / 3. Idealism / c. Empirical idealism
..But if he's a student of Berkeley... [Sommers,W]
The philosopher Berkeley once said.. [Sommers,W]
Dear Sir, Your astonishment's odd.... [Sommers,W]
There once was a man who said: 'God... [Sommers,W]
12. Knowledge Sources / B. Perception / 1. Perception
"My dog's got synaesthesia." How does he smell? ..... [Sommers,W]
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
A toper who spies in the distance... [Sommers,W]
16. Persons / F. Free Will / 6. Determinism / a. Determinism
There once was a man who said 'Damn!... [Sommers,W]
17. Mind and Body / B. Behaviourism / 4. Behaviourism Critique
How do behaviourists greet each other? [Sommers,W]
24. Political Theory / C. Ruling a State / 2. Leaders / d. Elites
'If you're aristocratic,' said Nietzsche... [Sommers,W]
24. Political Theory / D. Ideologies / 2. Anarchism
Why do anarchists drink herbal tea? [Sommers,W]
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]
26. Natural Theory / C. Causation / 9. General Causation / a. Constant conjunction
Cries the maid: 'You must marry me Hume!'... [Sommers,W]
Causation - we all thought we knew it/ Till Hume came along and saw through it/…. [Sommers,W]
27. Natural Reality / D. Time / 1. Nature of Time / c. Idealist time
The barman called 'Time!', and Augustine said..... [Sommers,W]
27. Natural Reality / D. Time / 2. Passage of Time / c. Tenses and time
The past, present and future walked into a bar.... [Sommers,W]
27. Natural Reality / G. Biology / 3. Evolution
Archelaus said life began in a primeval slime [Archelaus, by Schofield]