Combining Texts

All the ideas for 'Realistic Rationalism', 'Alfred Tarski: life and logic' and 'On the Foundations of Logic and Arithmetic'

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23 ideas

1. Philosophy / D. Nature of Philosophy / 3. Philosophy Defined
Traditionally philosophy is an a priori enquiry into general truths about reality [Katz]
Most of philosophy begins where science leaves off [Katz]
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]
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / b. Against mathematical platonism
'Real' maths objects have no causal role, no determinate reference, and no abstract/concrete distinction [Katz]
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / c. Against mathematical empiricism
The existence of an arbitrarily large number refutes the idea that numbers come from experience [Hilbert]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
Logic already contains some arithmetic, so the two must be developed together [Hilbert]
12. Knowledge Sources / A. A Priori Knowledge / 5. A Priori Synthetic
We don't have a clear enough sense of meaning to pronounce some sentences meaningless or just analytic [Katz]
12. Knowledge Sources / D. Empiricism / 5. Empiricism Critique
Experience cannot teach us why maths and logic are necessary [Katz]
19. Language / A. Nature of Meaning / 1. Meaning
Structuralists see meaning behaviouristically, and Chomsky says nothing about it [Katz]
19. Language / B. Reference / 4. Descriptive Reference / a. Sense and reference
It is generally accepted that sense is defined as the determiner of reference [Katz]
19. Language / C. Assigning Meanings / 5. Fregean Semantics
Sense determines meaning and synonymy, not referential properties like denotation and truth [Katz]
19. Language / D. Propositions / 2. Abstract Propositions / a. Propositions as sense
Sentences are abstract types (like musical scores), not individual tokens [Katz]