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All the ideas for 'What is Logic?st1=Ian Hacking', 'Axioms for the Part Relation' and 'Logological Fragments I'

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22 ideas

1. Philosophy / C. History of Philosophy / 1. History of Philosophy
19579 The history of philosophy is just experiments in how to do philosophy [Novalis]
1. Philosophy / D. Nature of Philosophy / 1. Philosophy
19583 Philosophy only begins when it studies itself [Novalis]
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]
5. Theory of Logic / L. Paradox / 2. Aporiai
19581 A problem is a solid mass, which the mind must break up [Novalis]
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / c. Counting procedure
19584 Whoever first counted to two must have seen the possibility of infinite counting [Novalis]
7. Existence / A. Nature of Existence / 3. Being / h. Dasein (being human)
22025 Novalis thought self-consciousness cannot disclose 'being', because we are temporal creatures [Novalis, by Pinkard]
9. Objects / C. Structure of Objects / 8. Parts of Objects / a. Parts of objects
10650 In the military, persons are parts of parts of large units, but not parts of those large units [Rescher]
11. Knowledge Aims / C. Knowing Reality / 3. Idealism / d. Absolute idealism
22067 Poetry is true idealism, and the self-consciousness of the universe [Novalis]
19. Language / F. Communication / 4. Private Language
19585 Every person has his own language [Novalis]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / b. Defining ethics
19582 Morality and philosophy are mutually dependent [Novalis]
23. Ethics / F. Existentialism / 7. Existential Action
22027 Life isn't given to us like a novel - we write the novel [Novalis]
25. Social Practice / E. Policies / 5. Education / c. Teaching
19580 If the pupil really yearns for the truth, they only need a hint [Novalis]