Combining Texts

All the ideas for 'Events and Their Names', 'On Formally Undecidable Propositions' and 'On Interpretation'

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39 ideas

2. Reason / B. Laws of Thought / 4. Contraries
1708 In "Callias is just/not just/unjust", which of these are contraries? [Aristotle]
3. Truth / B. Truthmakers / 10. Making Future Truths
1703 It is necessary that either a sea-fight occurs tomorrow or it doesn't, though neither option is in itself necessary [Aristotle]
3. Truth / C. Correspondence Truth / 1. Correspondence Truth
1704 Statements are true according to how things actually are [Aristotle]
3. Truth / F. Semantic Truth / 1. Tarski's Truth / a. Tarski's truth definition
21752 Prior to Gödel we thought truth in mathematics consisted in provability [Gödel, by Quine]
4. Formal Logic / A. Syllogistic Logic / 1. Aristotelian Logic
22272 Aristotle's later logic had to treat 'Socrates' as 'everything that is Socrates' [Potter on Aristotle]
9405 Square of Opposition: not both true, or not both false; one-way implication; opposite truth-values [Aristotle]
4. Formal Logic / D. Modal Logic ML / 1. Modal Logic
9728 Modal Square 1: □P and ¬◊¬P are 'contraries' of □¬P and ¬◊P [Aristotle, by Fitting/Mendelsohn]
9729 Modal Square 2: ¬□¬P and ◊P are 'subcontraries' of ¬□P and ◊¬P [Aristotle, by Fitting/Mendelsohn]
9730 Modal Square 3: □P and ¬◊¬P are 'contradictories' of ¬□P and ◊¬P [Aristotle, by Fitting/Mendelsohn]
9731 Modal Square 4: □¬P and ¬◊P are 'contradictories' of ¬□¬P and ◊P [Aristotle, by Fitting/Mendelsohn]
9732 Modal Square 5: □P and ¬◊¬P are 'subalternatives' of ¬□¬P and ◊P [Aristotle, by Fitting/Mendelsohn]
9733 Modal Square 6: □¬P and ¬◊P are 'subalternatives' of ¬□P and ◊¬P [Aristotle, by Fitting/Mendelsohn]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
17835 Gödel show that the incompleteness of set theory was a necessity [Gödel, by Hallett,M]
5. Theory of Logic / D. Assumptions for Logic / 1. Bivalence
21593 In talking of future sea-fights, Aristotle rejects bivalence [Aristotle, by Williamson]
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
1701 A prayer is a sentence which is neither true nor false [Aristotle]
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
17886 The limitations of axiomatisation were revealed by the incompleteness theorems [Gödel, by Koellner]
5. Theory of Logic / K. Features of Logics / 2. Consistency
10071 Second Incompleteness: nice theories can't prove their own consistency [Gödel, by Smith,P]
5. Theory of Logic / K. Features of Logics / 3. Soundness
19123 If soundness can't be proved internally, 'reflection principles' can be added to assert soundness [Gödel, by Halbach/Leigh]
5. Theory of Logic / K. Features of Logics / 5. Incompleteness
10621 Gödel's First Theorem sabotages logicism, and the Second sabotages Hilbert's Programme [Smith,P on Gödel]
17888 The undecidable sentence can be decided at a 'higher' level in the system [Gödel]
6. Mathematics / A. Nature of Mathematics / 1. Mathematics
10132 There can be no single consistent theory from which all mathematical truths can be derived [Gödel, by George/Velleman]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / g. Incompleteness of Arithmetic
3198 Gödel showed that arithmetic is either incomplete or inconsistent [Gödel, by Rey]
10072 First Incompleteness: arithmetic must always be incomplete [Gödel, by Smith,P]
9590 Arithmetical truth cannot be fully and formally derived from axioms and inference rules [Gödel, by Nagel/Newman]
11069 Gödel's Second says that semantic consequence outruns provability [Gödel, by Hanna]
10118 First Incompleteness: a decent consistent system is syntactically incomplete [Gödel, by George/Velleman]
10122 Second Incompleteness: a decent consistent system can't prove its own consistency [Gödel, by George/Velleman]
10611 There is a sentence which a theory can show is true iff it is unprovable [Gödel, by Smith,P]
10867 'This system can't prove this statement' makes it unprovable either way [Gödel, by Clegg]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / d. Predicativism
8747 Realists are happy with impredicative definitions, which describe entities in terms of other existing entities [Gödel, by Shapiro]
7. Existence / A. Nature of Existence / 3. Being / e. Being and nothing
1706 Non-existent things aren't made to exist by thought, because their non-existence is part of the thought [Aristotle]
7. Existence / A. Nature of Existence / 5. Reason for Existence
1707 Maybe necessity and non-necessity are the first principles of ontology [Aristotle]
7. Existence / B. Change in Existence / 4. Events / c. Reduction of events
8978 Events are made of other things, and are not fundamental to ontology [Bennett]
17. Mind and Body / C. Functionalism / 2. Machine Functionalism
3192 Basic logic can be done by syntax, with no semantics [Gödel, by Rey]
19. Language / A. Nature of Meaning / 2. Meaning as Mental
2337 For Aristotle meaning and reference are linked to concepts [Aristotle, by Putnam]
19. Language / D. Propositions / 4. Mental Propositions
13763 Spoken sounds vary between people, but are signs of affections of soul, which are the same for all [Aristotle]
19. Language / F. Communication / 3. Denial
1705 It doesn't have to be the case that in opposed views one is true and the other false [Aristotle]
26. Natural Theory / C. Causation / 8. Particular Causation / b. Causal relata
10364 Facts are about the world, not in it, so they can't cause anything [Bennett]
27. Natural Reality / D. Time / 1. Nature of Time / g. Growing block
1702 Things may be necessary once they occur, but not be unconditionally necessary [Aristotle]