Combining Texts

All the ideas for 'General Facts,Phys Necessity, and Metaph of Time', 'Alfred Tarski: life and logic' and 'Properties'

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30 ideas

2. Reason / B. Laws of Thought / 6. Ockham's Razor
What matters is not how many entities we postulate, but how many kinds of entities [Armstrong, by Mellor/Oliver]
3. Truth / B. Truthmakers / 3. Truthmaker Maximalism
The truth-maker principle is that every truth has a sufficient truth-maker [Forrest]
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]
8. Modes of Existence / B. Properties / 2. Need for Properties
Without properties we would be unable to express the laws of nature [Armstrong]
8. Modes of Existence / B. Properties / 10. Properties as Predicates
Whether we apply 'cold' or 'hot' to an object is quite separate from its change of temperature [Armstrong]
To the claim that every predicate has a property, start by eliminating failure of application of predicate [Armstrong]
8. Modes of Existence / B. Properties / 13. Tropes / a. Nature of tropes
Tropes fall into classes, because exact similarity is symmetrical and transitive [Armstrong]
8. Modes of Existence / B. Properties / 13. Tropes / b. Critique of tropes
Trope theory needs extra commitments, to symmetry and non-transitivity, unless resemblance is exact [Armstrong]
8. Modes of Existence / D. Universals / 2. Need for Universals
Universals are required to give a satisfactory account of the laws of nature [Armstrong]
8. Modes of Existence / E. Nominalism / 1. Nominalism / c. Nominalism about abstracta
Deniers of properties and relations rely on either predicates or on classes [Armstrong]
8. Modes of Existence / E. Nominalism / 2. Resemblance Nominalism
Resemblances must be in certain 'respects', and they seem awfully like properties [Armstrong]
8. Modes of Existence / E. Nominalism / 3. Predicate Nominalism
Change of temperature in objects is quite independent of the predicates 'hot' and 'cold' [Armstrong]
We want to know what constituents of objects are grounds for the application of predicates [Armstrong]
8. Modes of Existence / E. Nominalism / 5. Class Nominalism
In most sets there is no property common to all the members [Armstrong]
9. Objects / D. Essence of Objects / 15. Against Essentialism
Essences might support Resemblance Nominalism, but they are too coarse and ill-defined [Armstrong]
19. Language / C. Assigning Meanings / 3. Predicates
Predicates need ontological correlates to ensure that they apply [Armstrong]
There must be some explanation of why certain predicates are applicable to certain objects [Armstrong]
26. Natural Theory / D. Laws of Nature / 4. Regularities / a. Regularity theory
Regularities theories are poor on causal connections, counterfactuals and probability [Armstrong]
The introduction of sparse properties avoids the regularity theory's problem with 'grue' [Armstrong]