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All the ideas for 'talk', 'Introduction to Mathematical Logic' and 'Realistic Rationalism'

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29 ideas

1. Philosophy / D. Nature of Philosophy / 3. Philosophy Defined
2516 Most of philosophy begins where science leaves off [Katz]
2510 Traditionally philosophy is an a priori enquiry into general truths about reality [Katz]
4. Formal Logic / B. Propositional Logic PL / 1. Propositional Logic
17749 Post proved the consistency of propositional logic in 1921 [Walicki]
17765 Propositional language can only relate statements as the same or as different [Walicki]
4. Formal Logic / B. Propositional Logic PL / 3. Truth Tables
17764 Boolean connectives are interpreted as functions on the set {1,0} [Walicki]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
17752 The empty set is useful for defining sets by properties, when the members are not yet known [Walicki]
17753 The empty set avoids having to take special precautions in case members vanish [Walicki]
4. Formal Logic / F. Set Theory ST / 6. Ordering in Sets
17759 Ordinals play the central role in set theory, providing the model of well-ordering [Walicki]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
17741 To determine the patterns in logic, one must identify its 'building blocks' [Walicki]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
17747 A 'model' of a theory specifies interpreting a language in a domain to make all theorems true [Walicki]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
17748 The L-S Theorem says no theory (even of reals) says more than a natural number theory [Walicki]
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
17763 Axiomatic systems are purely syntactic, and do not presuppose any interpretation [Walicki]
17761 A compact axiomatisation makes it possible to understand a field as a whole [Walicki]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
17757 Members of ordinals are ordinals, and also subsets of ordinals [Walicki]
17758 Ordinals are transitive sets of transitive sets; or transitive sets totally ordered by inclusion [Walicki]
17755 Ordinals are the empty set, union with the singleton, and any arbitrary union of ordinals [Walicki]
17756 The union of finite ordinals is the first 'limit ordinal'; 2ω is the second... [Walicki]
17760 Two infinite ordinals can represent a single infinite cardinal [Walicki]
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
17762 In non-Euclidean geometry, all Euclidean theorems are valid that avoid the fifth postulate [Walicki]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / f. Mathematical induction
17754 Inductive proof depends on the choice of the ordering [Walicki]
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / b. Against mathematical platonism
2521 'Real' maths objects have no causal role, no determinate reference, and no abstract/concrete distinction [Katz]
10. Modality / A. Necessity / 2. Nature of Necessity
17742 Scotus based modality on semantic consistency, instead of on what the future could allow [Walicki]
12. Knowledge Sources / A. A Priori Knowledge / 5. A Priori Synthetic
2513 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
2522 Experience cannot teach us why maths and logic are necessary [Katz]
13. Knowledge Criteria / E. Relativism / 2. Knowledge as Convention
1556 By nature people are close to one another, but culture drives them apart [Hippias]
19. Language / A. Nature of Meaning / 1. Meaning
2517 Structuralists see meaning behaviouristically, and Chomsky says nothing about it [Katz]
19. Language / B. Reference / 4. Descriptive Reference / a. Sense and reference
2519 It is generally accepted that sense is defined as the determiner of reference [Katz]
19. Language / C. Assigning Meanings / 5. Fregean Semantics
2520 Sense determines meaning and synonymy, not referential properties like denotation and truth [Katz]
19. Language / D. Propositions / 2. Abstract Propositions / a. Propositions as sense
2518 Sentences are abstract types (like musical scores), not individual tokens [Katz]