Combining Texts

All the ideas for 'Truth (frags)', 'Logical Consequence' and 'Noneism or Allism?'

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12 ideas

4. Formal Logic / A. Syllogistic Logic / 2. Syllogistic Logic
10688 'Equivocation' is when terms do not mean the same thing in premises and conclusion [Beall/Restall]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
10690 Formal logic is invariant under permutations, or devoid of content, or gives the norms for thought [Beall/Restall]
5. Theory of Logic / B. Logical Consequence / 2. Types of Consequence
10691 Logical consequence needs either proofs, or absence of counterexamples [Beall/Restall]
5. Theory of Logic / B. Logical Consequence / 4. Semantic Consequence |=
10695 Logical consequence is either necessary truth preservation, or preservation based on interpretation [Beall/Restall]
5. Theory of Logic / B. Logical Consequence / 8. Material Implication
10689 A step is a 'material consequence' if we need contents as well as form [Beall/Restall]
5. Theory of Logic / G. Quantification / 4. Substitutional Quantification
15533 We can quantify over fictions by quantifying for real over their names [Lewis]
5. Theory of Logic / G. Quantification / 7. Unorthodox Quantification
15534 We could quantify over impossible objects - as bundles of properties [Lewis]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
10696 A 'logical truth' (or 'tautology', or 'theorem') follows from empty premises [Beall/Restall]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
10693 Models are mathematical structures which interpret the non-logical primitives [Beall/Restall]
6. Mathematics / B. Foundations for Mathematics / 2. Proof in Mathematics
10692 Hilbert proofs have simple rules and complex axioms, and natural deduction is the opposite [Beall/Restall]
7. Existence / A. Nature of Existence / 1. Nature of Existence
15532 'Allists' embrace the existence of all controversial entities; 'noneists' reject all but the obvious ones [Lewis]
7. Existence / A. Nature of Existence / 2. Types of Existence
15535 We can't accept a use of 'existence' that says only some of the things there are actually exist [Lewis]