Combining Texts

All the ideas for 'Substance and Individuation in Leibniz', 'On Freedom' and 'Higher-Order Logic'

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28 ideas

4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
The axiom of choice is controversial, but it could be replaced [Shapiro]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
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
Some say that second-order logic is mathematics, not logic [Shapiro]
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
Logical consequence can be defined in terms of the logical terminology [Shapiro]
5. Theory of Logic / G. Quantification / 5. Second-Order Quantification
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
The Löwenheim-Skolem theorem seems to be a defect of first-order logic [Shapiro]
Up Löwenheim-Skolem: if natural numbers satisfy wffs, then an infinite domain satisfies them [Shapiro]
Downward Löwenheim-Skolem: if there's an infinite model, there is a countable model [Shapiro]
The Löwenheim-Skolem Theorems fail for second-order languages with standard semantics [Shapiro]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / e. Peano arithmetic 2nd-order
Second-order logic has the expressive power for mathematics, but an unworkable model theory [Shapiro]
8. Modes of Existence / A. Relations / 1. Nature of Relations
Scholastics treat relations as two separate predicates of the relata [Cover/O'Leary-Hawthorne]
8. Modes of Existence / B. Properties / 11. Properties as Sets
Logicians use 'property' and 'set' interchangeably, with little hanging on it [Shapiro]
9. Objects / A. Existence of Objects / 5. Individuation / a. Individuation
If you individuate things by their origin, you still have to individuate the origins themselves [Cover/O'Leary-Hawthorne]
Numerical difference is a symmetrical notion, unlike proper individuation [Cover/O'Leary-Hawthorne]
9. Objects / A. Existence of Objects / 5. Individuation / d. Individuation by haecceity
Haecceity as property, or as colourless thisness, or as singleton set [Cover/O'Leary-Hawthorne]
9. Objects / B. Unity of Objects / 2. Substance / a. Substance
Maybe 'substance' is more of a mass-noun than a count-noun [Cover/O'Leary-Hawthorne]
9. Objects / B. Unity of Objects / 2. Substance / c. Types of substance
We can ask for the nature of substance, about type of substance, and about individual substances [Cover/O'Leary-Hawthorne]
9. Objects / B. Unity of Objects / 2. Substance / d. Substance defined
The general assumption is that substances cannot possibly be non-substances [Cover/O'Leary-Hawthorne]
9. Objects / D. Essence of Objects / 7. Essence and Necessity / a. Essence as necessary properties
Modern essences are sets of essential predicate-functions [Cover/O'Leary-Hawthorne]
Modern essentialists express essence as functions from worlds to extensions for predicates [Cover/O'Leary-Hawthorne]
9. Objects / E. Objects over Time / 12. Origin as Essential
Necessity-of-origin won't distinguish ex nihilo creations, or things sharing an origin [Cover/O'Leary-Hawthorne]
10. Modality / B. Possibility / 5. Contingency
Necessary truths can be analysed into original truths; contingent truths are infinitely analysable [Leibniz]
10. Modality / D. Knowledge of Modality / 2. A Priori Contingent
Only God sees contingent truths a priori [Leibniz]
10. Modality / E. Possible worlds / 3. Transworld Objects / a. Transworld identity
Even extreme modal realists might allow transworld identity for abstract objects [Cover/O'Leary-Hawthorne]
10. Modality / E. Possible worlds / 3. Transworld Objects / e. Possible Objects
If non-existents are possible, their existence would replace what now exists, which cannot therefore be necessary [Leibniz]
14. Science / D. Explanation / 2. Types of Explanation / c. Explanations by coherence
We can go beyond mere causal explanations if we believe in an 'order of being' [Cover/O'Leary-Hawthorne]
28. God / A. Divine Nature / 3. Divine Perfections
God does everything in a perfect way, and never acts contrary to reason [Leibniz]