Combining Texts

All the ideas for 'The Case for Closure', 'A Theory of Universals' and 'Higher-Order Logic'

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23 ideas

4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / g. System S4
15544 If what is actual might have been impossible, we need S4 modal logic [Armstrong, by Lewis]
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
10297 The Löwenheim-Skolem theorem seems to be a defect of first-order logic [Shapiro]
10590 Up Löwenheim-Skolem: if natural numbers satisfy wffs, then an infinite domain satisfies them [Shapiro]
10292 Downward Löwenheim-Skolem: if there's an infinite model, there is a countable model [Shapiro]
10296 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
10294 Second-order logic has the expressive power for mathematics, but an unworkable model theory [Shapiro]
8. Modes of Existence / B. Properties / 1. Nature of Properties
7024 Properties are universals, which are always instantiated [Armstrong, by Heil]
8. Modes of Existence / B. Properties / 6. Categorical Properties
9478 Even if all properties are categorical, they may be denoted by dispositional predicates [Armstrong, by Bird]
8. Modes of Existence / B. Properties / 11. Properties as Sets
10591 Logicians use 'property' and 'set' interchangeably, with little hanging on it [Shapiro]
8. Modes of Existence / D. Universals / 2. Need for Universals
10729 Universals explain resemblance and causal power [Armstrong, by Oliver]
8. Modes of Existence / E. Nominalism / 3. Predicate Nominalism
4031 It doesn't follow that because there is a predicate there must therefore exist a property [Armstrong]
9. Objects / F. Identity among Objects / 4. Type Identity
10024 The type-token distinction is the universal-particular distinction [Armstrong, by Hodes]
9. Objects / F. Identity among Objects / 5. Self-Identity
10728 A thing's self-identity can't be a universal, since we can know it a priori [Armstrong, by Oliver]
11. Knowledge Aims / B. Certain Knowledge / 2. Common Sense Certainty
19553 Commitment to 'I have a hand' only makes sense in a context where it has been doubted [Hawthorne]
13. Knowledge Criteria / A. Justification Problems / 2. Justification Challenges / c. Knowledge closure
19551 How can we know the heavyweight implications of normal knowledge? Must we distort 'knowledge'? [Hawthorne]
19552 We wouldn't know the logical implications of our knowledge if small risks added up to big risks [Hawthorne]
19554 Denying closure is denying we know P when we know P and Q, which is absurd in simple cases [Hawthorne]