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All the ideas for 'What is Logic?st1=Ian Hacking', 'fragments/reports' and 'On Carnap's Views on Ontology'

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19 ideas

1. Philosophy / E. Nature of Metaphysics / 4. Metaphysics as Science
Quine rejects Carnap's view that science and philosophy are distinct [Quine, by Boulter]
2. Reason / D. Definition / 3. Types of Definition
A decent modern definition should always imply a semantics [Hacking]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / d. Basic theorems of PL
'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking]
Gentzen's Cut Rule (or transitivity of deduction) is 'If A |- B and B |- C, then A |- C' [Hacking]
Only Cut reduces complexity, so logic is constructive without it, and it can be dispensed with [Hacking]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
The various logics are abstractions made from terms like 'if...then' in English [Hacking]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking]
A limitation of first-order logic is that it cannot handle branching quantifiers [Hacking]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Second-order completeness seems to need intensional entities and possible worlds [Hacking]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
With a pure notion of truth and consequence, the meanings of connectives are fixed syntactically [Hacking]
5. Theory of Logic / E. Structures of Logic / 4. Variables in Logic
Perhaps variables could be dispensed with, by arrows joining places in the scope of quantifiers [Hacking]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking]
7. Existence / D. Theories of Reality / 11. Ontological Commitment / a. Ontological commitment
Names have no ontological commitment, because we can deny that they name anything [Quine]
7. Existence / D. Theories of Reality / 11. Ontological Commitment / b. Commitment of quantifiers
We can use quantification for commitment to unnameable things like the real numbers [Quine]
19. Language / E. Analyticity / 3. Analytic and Synthetic
Without the analytic/synthetic distinction, Carnap's ontology/empirical distinction collapses [Quine]
23. Ethics / C. Virtue Theory / 1. Virtue Theory / a. Nature of virtue
We must choose in which of the virtues we wish to excel [Panaetius]
23. Ethics / C. Virtue Theory / 2. Elements of Virtue Theory / b. Living naturally
Panaetius said we should live according to our natural starting-points [Panaetius, by Asmis]
23. Ethics / C. Virtue Theory / 3. Virtues / d. Courage
Panaetius identified courage with great-mindedness, preferring civic courage to military [Panaetius, by Asmis]
29. Religion / D. Religious Issues / 2. Immortality / a. Immortality
Souls are born, since they are sensitive and inherited, so they must perish [Panaetius, by Cicero]