Combining Texts

All the ideas for 'fragments/reports', 'The Correspondence Theory of Truth' and 'Higher-Order Logic'

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21 ideas

3. Truth / A. Truth Problems / 5. Truth Bearers
Must sentences make statements to qualify for truth? [O'Connor]
3. Truth / C. Correspondence Truth / 1. Correspondence Truth
Beliefs must match facts, but also words must match beliefs [O'Connor]
3. Truth / F. Semantic Truth / 2. Semantic Truth
The semantic theory requires sentences as truth-bearers, not propositions [O'Connor]
What does 'true in English' mean? [O'Connor]
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 / 4. Pure Logic
Logic seems to work for unasserted sentences [O'Connor]
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]
7. Existence / B. Change in Existence / 4. Events / c. Reduction of events
Events are fast changes which are of interest to us [O'Connor]
8. Modes of Existence / B. Properties / 11. Properties as Sets
Logicians use 'property' and 'set' interchangeably, with little hanging on it [Shapiro]
10. Modality / A. Necessity / 8. Transcendental Necessity
Everything happens by reason and necessity [Leucippus]
11. Knowledge Aims / A. Knowledge / 4. Belief / a. Beliefs
Without language our beliefs are particular and present [O'Connor]
We can't contemplate our beliefs until we have expressed them [O'Connor]