Combining Texts

All the ideas for 'fragments/reports', 'In Defence of Convention T' and 'Alfred Tarski: life and logic'

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17 ideas

4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
The Axiom of Choice is consistent with the other axioms of set theory [Feferman/Feferman]
Axiom of Choice: a set exists which chooses just one element each of any set of sets [Feferman/Feferman]
Platonist will accept the Axiom of Choice, but others want criteria of selection or definition [Feferman/Feferman]
The Trichotomy Principle is equivalent to the Axiom of Choice [Feferman/Feferman]
Cantor's theories needed the Axiom of Choice, but it has led to great controversy [Feferman/Feferman]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
A structure is a 'model' when the axioms are true. So which of the structures are models? [Feferman/Feferman]
Tarski and Vaught established the equivalence relations between first-order structures [Feferman/Feferman]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
Löwenheim-Skolem says if the sentences are countable, so is the model [Feferman/Feferman]
Löwenheim-Skolem Theorem, and Gödel's completeness of first-order logic, the earliest model theory [Feferman/Feferman]
5. Theory of Logic / K. Features of Logics / 4. Completeness
If a sentence holds in every model of a theory, then it is logically derivable from the theory [Feferman/Feferman]
5. Theory of Logic / K. Features of Logics / 7. Decidability
'Recursion theory' concerns what can be solved by computing machines [Feferman/Feferman]
Both Principia Mathematica and Peano Arithmetic are undecidable [Feferman/Feferman]
19. Language / C. Assigning Meanings / 5. Fregean Semantics
A theory of meaning comes down to translating sentences into Fregean symbolic logic [Davidson, by Macey]
23. Ethics / C. Virtue Theory / 1. Virtue Theory / a. Nature of virtue
We must choose in which of the virtues we wish to excel [Panaetius]
23. Ethics / C. Virtue Theory / 2. Elements of Virtue Theory / b. Living naturally
Panaetius said we should live according to our natural starting-points [Panaetius, by Asmis]
23. Ethics / C. Virtue Theory / 3. Virtues / d. Courage
Panaetius identified courage with great-mindedness, preferring civic courage to military [Panaetius, by Asmis]
29. Religion / D. Religious Issues / 2. Immortality / a. Immortality
Souls are born, since they are sensitive and inherited, so they must perish [Panaetius, by Cicero]