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All the ideas for 'What is Logic?st1=Ian Hacking', 'Science and Hypothesis' and 'A Philosophy of Boredom'

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23 ideas

1. Philosophy / B. History of Ideas / 5. Later European Thought
Modern Western culture suddenly appeared in Jena in the 1790s [Svendsen]
1. Philosophy / F. Analytic Philosophy / 7. Limitations of Analysis
You can't understand love in terms of 'if and only if...' [Svendsen]
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]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
Mathematicians do not study objects, but relations between objects [Poincaré]
12. Knowledge Sources / B. Perception / 2. Qualities in Perception / e. Primary/secondary critique
If subjective and objective begin to merge, then so do primary and secondary qualities [Svendsen]
18. Thought / A. Modes of Thought / 3. Emotions / b. Types of emotion
Emotions have intentional objects, while a mood is objectless [Svendsen]
22. Metaethics / B. Value / 2. Values / e. Death
Death appears to be more frightening the less one has lived [Svendsen]
23. Ethics / F. Existentialism / 4. Boredom
We can be unaware that we are bored [Svendsen]
Boredom is so radical that suicide could not overcome it; only never having existed would do it [Svendsen]
We are bored because everything comes to us fully encoded, and we want personal meaning [Svendsen]
The profoundest boredom is boredom with boredom [Svendsen]
24. Political Theory / B. Nature of a State / 1. Purpose of a State
We have achieved a sort of utopia, and it is boring, so that is the end of utopias [Svendsen]
24. Political Theory / D. Ideologies / 9. Communism
The concept of 'alienation' seems no longer applicable [Svendsen]