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All the ideas for 'What is Logic?st1=Ian Hacking', 'Quodlibeta' and 'reports'

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24 ideas

1. Philosophy / D. Nature of Philosophy / 2. Invocation to Philosophy
1765 Diogenes said avoidance of philosophy is the lack of a desire to live properly [Diogenes of Sin., by Diog. Laertius]
2. Reason / D. Definition / 3. Types of Definition
13838 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
13834 Gentzen's Cut Rule (or transitivity of deduction) is 'If A |- B and B |- C, then A |- C' [Hacking]
13835 Only Cut reduces complexity, so logic is constructive without it, and it can be dispensed with [Hacking]
13833 'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
13845 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
13840 First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking]
13844 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
13842 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
13837 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
13839 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
13843 If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking]
7. Existence / E. Categories / 3. Proposed Categories
16657 Substance, Quantity and Quality are real; other categories depend on those three [Henry of Ghent]
8. Modes of Existence / A. Relations / 1. Nature of Relations
16658 The only reality in the category of Relation is things from another category [Henry of Ghent]
8. Modes of Existence / B. Properties / 8. Properties as Modes
16645 Accidents are diminished beings, because they are dispositions of substance (unqualified being) [Henry of Ghent]
11. Knowledge Aims / C. Knowing Reality / 3. Idealism / b. Transcendental idealism
22012 Kant says things-in-themselves cause sensations, but then makes causation transcendental! [Henry of Ghent, by Pinkard]
13. Knowledge Criteria / D. Scepticism / 6. Scepticism Critique
1762 When someone denied motion, Diogenes got up and walked away [Diogenes of Sin., by Diog. Laertius]
20. Action / C. Motives for Action / 3. Acting on Reason / b. Intellectualism
7813 Cynicism was open to anyone, and needed neither education nor sophistication [Diogenes of Sin., by Grayling]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / e. Human nature
1763 Diogenes said a plucked chicken fits Plato's definition of man [Diogenes of Sin., by Diog. Laertius]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / j. Ethics by convention
5071 The Cynics rejected what is conventional as irrational, and aimed to live by nature [Taylor,R on Diogenes of Sin.]
22. Metaethics / C. The Good / 2. Happiness / d. Routes to happiness
7812 For peace of mind, you need self-government, indifference and independence [Diogenes of Sin.]
24. Political Theory / B. Nature of a State / 4. Citizenship
1764 Diogenes said he was a citizen of the world [Diogenes of Sin., by Diog. Laertius]
24. Political Theory / D. Ideologies / 2. Anarchism
5968 Diogenes masturbated in public, wishing he could get rid of hunger so easily [Diogenes of Sin., by Plutarch]
25. Social Practice / A. Freedoms / 3. Free speech
1766 Diogenes said that the most excellent thing among men was freedom of speech [Diogenes of Sin., by Diog. Laertius]