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All the ideas for 'Laches', 'works' and 'Alfred Tarski: life and logic'

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22 ideas

1. Philosophy / A. Wisdom / 3. Wisdom Deflated
Don't assume that wisdom is the automatic consequence of old age [Plato]
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]
4. Formal Logic / G. Formal Mereology / 1. Mereology
Abelard's mereology involves privileged and natural divisions, and principal parts [Abelard, by King,P]
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]
8. Modes of Existence / E. Nominalism / 1. Nominalism / b. Nominalism about universals
If 'animal' is wholly present in Socrates and an ass, then 'animal' is rational and irrational [Abelard, by King,P]
Abelard was an irrealist about virtually everything apart from concrete individuals [Abelard, by King,P]
8. Modes of Existence / E. Nominalism / 3. Predicate Nominalism
Only words can be 'predicated of many'; the universality is just in its mode of signifying [Abelard, by Panaccio]
10. Modality / A. Necessity / 4. De re / De dicto modality
The de dicto-de re modality distinction dates back to Abelard [Abelard, by Orenstein]
18. Thought / E. Abstraction / 8. Abstractionism Critique
Abelard's problem is the purely singular aspects of things won't account for abstraction [Panaccio on Abelard]
19. Language / C. Assigning Meanings / 3. Predicates
Nothing external can truly be predicated of an object [Abelard, by Panaccio]
23. Ethics / C. Virtue Theory / 3. Virtues / d. Courage
Being unafraid (perhaps through ignorance) and being brave are two different things [Plato]
26. Natural Theory / B. Natural Kinds / 7. Critique of Kinds
Natural kinds are not special; they are just well-defined resemblance collections [Abelard, by King,P]