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All the ideas for 'What is Logic?st1=Ian Hacking', 'works' and 'The Mysterious Flame'

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20 ideas

1. Philosophy / E. Nature of Metaphysics / 5. Metaphysics beyond Science
Philosophy is a magnificent failure in its attempt to overstep the limits of our knowledge [McGinn]
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
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]
'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
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 / 1. Logical Form
Thoughts have a dual aspect: as they seem to introspection, and their underlying logical reality [McGinn]
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]
15. Nature of Minds / C. Capacities of Minds / 1. Faculties
Mental modules for language, social, action, theory, space, emotion [McGinn]
16. Persons / F. Free Will / 1. Nature of Free Will
Free will is mental causation in action [McGinn]
17. Mind and Body / A. Mind-Body Dualism / 3. Panpsychism
Brains aren't made of anything special, suggesting panpsychism [McGinn]
17. Mind and Body / D. Property Dualism / 6. Mysterianism
Examining mind sees no brain; examining brain sees no mind [McGinn]
19. Language / C. Assigning Meanings / 6. Truth-Conditions Semantics
There is information if there are symbols which refer, and which can combine into a truth or falsehood [McGinn]
23. Ethics / F. Existentialism / 6. Authentic Self
Sartre gradually realised that freedom is curtailed by the weight of situation [Sartre, by Daigle]
26. Natural Theory / C. Causation / 4. Naturalised causation
Causation in the material world is energy-transfer, of motion, electricity or gravity [McGinn]