Combining Texts

All the ideas for 'Leibniz', 'Higher-Order Logic' and 'Essential Attribution'

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22 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 / C. Structure of Objects / 2. Hylomorphism / a. Hylomorphism
11181 Aristotelian essentialism involves a 'natural' or 'causal' interpretation of modal operators [Marcus (Barcan)]
11184 Aristotelian essentialism is about shared properties, individuating essentialism about distinctive properties [Marcus (Barcan)]
9. Objects / D. Essence of Objects / 7. Essence and Necessity / b. Essence not necessities
11180 Essentialist sentences are not theorems of modal logic, and can even be false [Marcus (Barcan)]
11186 'Essentially' won't replace 'necessarily' for vacuous properties like snub-nosed or self-identical [Marcus (Barcan)]
11185 'Is essentially' has a different meaning from 'is necessarily', as they often cannot be substituted [Marcus (Barcan)]
9. Objects / D. Essence of Objects / 14. Knowledge of Essences
11182 If essences are objects with only essential properties, they are elusive in possible worlds [Marcus (Barcan)]
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
7566 The Identity of Indiscernibles is really the same as the verification principle [Jolley]
10. Modality / E. Possible worlds / 1. Possible Worlds / a. Possible worlds
11183 The use of possible worlds is to sort properties (not to individuate objects) [Marcus (Barcan)]
10. Modality / E. Possible worlds / 3. Transworld Objects / b. Rigid designation
11187 In possible worlds, names are just neutral unvarying pegs for truths and predicates [Marcus (Barcan)]
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / a. Scientific essentialism
11189 Dispositional essences are special, as if an object loses them they cease to exist [Marcus (Barcan)]