Combining Texts

All the ideas for 'The Roots of Reference', 'A Tour through Mathematical Logic' and 'Truth-makers and dependence'

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29 ideas

3. Truth / B. Truthmakers / 2. Truthmaker Relation
17325 Truth-maker theory can't cope with non-causal dependence [Liggins]
3. Truth / B. Truthmakers / 12. Rejecting Truthmakers
17318 Truthmakers for existence is fine; otherwise maybe restrict it to synthetic truths? [Liggins]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / b. Terminology of PL
13520 A 'tautology' must include connectives [Wolf,RS]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / c. Derivation rules of PL
13524 Deduction Theorem: T∪{P}|-Q, then T|-(P→Q), which justifies Conditional Proof [Wolf,RS]
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / d. Universal quantifier ∀
13522 Universal Generalization: If we prove P(x) with no special assumptions, we can conclude ∀xP(x) [Wolf,RS]
13521 Universal Specification: ∀xP(x) implies P(t). True for all? Then true for an instance [Wolf,RS]
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / e. Existential quantifier ∃
13523 Existential Generalization (or 'proof by example'): if we can say P(t), then we can say something is P [Wolf,RS]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / e. Axiom of the Empty Set IV
13529 Empty Set: ∃x∀y ¬(y∈x). The unique empty set exists [Wolf,RS]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / n. Axiom of Comprehension
13526 Comprehension Axiom: if a collection is clearly specified, it is a set [Wolf,RS]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
13534 In first-order logic syntactic and semantic consequence (|- and |=) nicely coincide [Wolf,RS]
13535 First-order logic is weakly complete (valid sentences are provable); we can't prove every sentence or its negation [Wolf,RS]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
13531 Model theory reveals the structures of mathematics [Wolf,RS]
13532 Model theory 'structures' have a 'universe', some 'relations', some 'functions', and some 'constants' [Wolf,RS]
13519 Model theory uses sets to show that mathematical deduction fits mathematical truth [Wolf,RS]
13533 First-order model theory rests on completeness, compactness, and the Löwenheim-Skolem-Tarski theorem [Wolf,RS]
5. Theory of Logic / J. Model Theory in Logic / 2. Isomorphisms
13537 An 'isomorphism' is a bijection that preserves all structural components [Wolf,RS]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
13539 The LST Theorem is a serious limitation of first-order logic [Wolf,RS]
5. Theory of Logic / K. Features of Logics / 4. Completeness
13538 If a theory is complete, only a more powerful language can strengthen it [Wolf,RS]
5. Theory of Logic / K. Features of Logics / 10. Monotonicity
13525 Most deductive logic (unlike ordinary reasoning) is 'monotonic' - we don't retract after new givens [Wolf,RS]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
13530 An ordinal is an equivalence class of well-orderings, or a transitive set whose members are transitive [Wolf,RS]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
13518 Modern mathematics has unified all of its objects within set theory [Wolf,RS]
7. Existence / A. Nature of Existence / 5. Reason for Existence
17320 Either p is true or not-p is true, so something is true, so something exists [Liggins]
7. Existence / C. Structure of Existence / 1. Grounding / b. Relata of grounding
17326 The dependence of {Socrates} on Socrates involves a set and a philosopher, not facts [Liggins]
7. Existence / C. Structure of Existence / 4. Ontological Dependence
17327 Non-causal dependence is at present only dimly understood [Liggins]
7. Existence / C. Structure of Existence / 5. Supervenience / c. Significance of supervenience
17322 Necessities supervene on everything, but don't depend on everything [Liggins]
8. Modes of Existence / C. Powers and Dispositions / 3. Powers as Derived
14296 Dispositions are physical states of mechanism; when known, these replace the old disposition term [Quine]
14. Science / D. Explanation / 1. Explanation / a. Explanation
17324 'Because' can signal an inference rather than an explanation [Liggins]
14. Science / D. Explanation / 2. Types of Explanation / a. Types of explanation
17321 Value, constitution and realisation are non-causal dependences that explain [Liggins]
17323 If explanations track dependence, then 'determinative' explanations seem to exist [Liggins]