Combining Texts

All the ideas for 'Essence and Being', 'Higher-Order Logic' and 'Speeches in Elberfeld'

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19 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 / 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]
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 / D. Essence of Objects / 1. Essences of Objects
14221 Serious essentialism says everything has essences, they're not things, and they ground necessities [Shalkowski]
9. Objects / D. Essence of Objects / 6. Essence as Unifier
14222 Essences are what it is to be that (kind of) thing - in fact, they are the thing's identity [Shalkowski]
9. Objects / D. Essence of Objects / 13. Nominal Essence
14226 We distinguish objects by their attributes, not by their essences [Shalkowski]
9. Objects / D. Essence of Objects / 15. Against Essentialism
14225 Critics say that essences are too mysterious to be known [Shalkowski]
10. Modality / A. Necessity / 4. De re / De dicto modality
14223 De dicto necessity has linguistic entities as their source, so it is a type of de re necessity [Shalkowski]
19. Language / C. Assigning Meanings / 7. Extensional Semantics
14224 Equilateral and equiangular aren't the same, as we have to prove their connection [Shalkowski]
24. Political Theory / D. Ideologies / 11. Capitalism
20525 Free markets lead to boom and bust, pointless middlemen, and alienated workers [Engels]