Combining Texts

All the ideas for 'fragments/reports', 'Higher-Order Logic' and 'Ontological Relativity'

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21 ideas

4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
10301 The axiom of choice is controversial, but it could be replaced [Shapiro]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
10588 First-order logic is Complete, and Compact, with the Löwenheim-Skolem Theorems [Shapiro]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
10298 Some say that second-order logic is mathematics, not logic [Shapiro]
10299 If the aim of logic is to codify inferences, second-order logic is useless [Shapiro]
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
10300 Logical consequence can be defined in terms of the logical terminology [Shapiro]
5. Theory of Logic / G. Quantification / 4. Substitutional Quantification
21642 If quantification is all substitutional, there is no ontology [Quine]
5. Theory of Logic / G. Quantification / 5. Second-Order Quantification
10290 Second-order variables also range over properties, sets, relations or functions [Shapiro]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
10590 Up Löwenheim-Skolem: if natural numbers satisfy wffs, then an infinite domain satisfies them [Shapiro]
10296 The Löwenheim-Skolem Theorems fail for second-order languages with standard semantics [Shapiro]
10297 The Löwenheim-Skolem theorem seems to be a defect of first-order logic [Shapiro]
10292 Downward Löwenheim-Skolem: if there's an infinite model, there is a countable model [Shapiro]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / e. Peano arithmetic 2nd-order
10294 Second-order logic has the expressive power for mathematics, but an unworkable model theory [Shapiro]
7. Existence / A. Nature of Existence / 6. Criterion for Existence
1633 Absolute ontological questions are meaningless, because the answers are circular definitions [Quine]
7. Existence / D. Theories of Reality / 11. Ontological Commitment / d. Commitment of theories
18964 Ontology is relative to both a background theory and a translation manual [Quine]
8. Modes of Existence / B. Properties / 11. Properties as Sets
10591 Logicians use 'property' and 'set' interchangeably, with little hanging on it [Shapiro]
9. Objects / F. Identity among Objects / 1. Concept of Identity
18965 We know what things are by distinguishing them, so identity is part of ontology [Quine]
13. Knowledge Criteria / E. Relativism / 5. Language Relativism
1634 Two things are relative - the background theory, and translating the object theory into the background theory [Quine]
19. Language / B. Reference / 1. Reference theories
8470 Reference is inscrutable, because we cannot choose between theories of numbers [Quine, by Orenstein]
19. Language / F. Communication / 6. Interpreting Language / b. Indeterminate translation
18963 Indeterminacy translating 'rabbit' depends on translating individuation terms [Quine]
25. Social Practice / E. Policies / 5. Education / b. Education principles
13304 Learned men gain more in one day than others do in a lifetime [Posidonius]
27. Natural Reality / D. Time / 1. Nature of Time / d. Time as measure
20820 Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus]