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All the ideas for 'What is Logic?st1=Ian Hacking', '24: Book of Jeremiah' and 'What is Art?'

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21 ideas

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]
21. Aesthetics / B. Nature of Art / 4. Art as Expression
True works of art transmit completely new feelings [Tolstoy]
Art is when one man uses external signs to hand on his feelings to another man [Tolstoy]
The highest feelings of mankind can only be transmitted by art [Tolstoy]
21. Aesthetics / C. Artistic Issues / 4. Emotion in Art
The purpose of art is to help mankind to evolve better, more socially beneficial feelings [Tolstoy]
21. Aesthetics / C. Artistic Issues / 7. Art and Morality
People estimate art according to their moral values [Tolstoy]
The upper classes put beauty first, and thus freed themselves from morality [Tolstoy]
We separate the concept of beauty from goodness, unlike the ancients [Tolstoy]
24. Political Theory / B. Nature of a State / 1. Purpose of a State
Jeremiah implied a link between weakness and goodness, and the evil of the state [Jeremiah, by Johnson,P]
28. God / A. Divine Nature / 3. Divine Perfections
Do I not fill heaven and earth? saith the Lord [Jeremiah]
28. God / C. Attitudes to God / 3. Deism
Am I a God afar off, and not a God close at hand? [Jeremiah]