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All the ideas for 'What is Logic?st1=Ian Hacking', 'Fallibilism' and 'Supervenience'

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22 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]
7. Existence / C. Structure of Existence / 5. Supervenience / a. Nature of supervenience
Supervenience: No A-difference without a B-difference [Bennett,K]
Supervenience is non-symmetric - sometimes it's symmetric, and sometimes it's one-way [Bennett,K]
7. Existence / C. Structure of Existence / 5. Supervenience / b. Types of supervenience
Weak supervenience is in one world, strong supervenience in all possible worlds [Bennett,K]
7. Existence / C. Structure of Existence / 5. Supervenience / c. Significance of supervenience
Aesthetics, morality and mind supervene on the physical? Modal on non-modal? General on particular? [Bennett,K]
Some entailments do not involve supervenience, as when brotherhood entails siblinghood [Bennett,K]
Reduction requires supervenience, but does supervenience suffice for reduction? [Bennett,K]
7. Existence / D. Theories of Reality / 6. Physicalism
Definitions of physicalism are compatible with a necessary God [Bennett,K]
10. Modality / A. Necessity / 6. Logical Necessity
The metaphysically and logically possible worlds are the same, so they are the same strength [Bennett,K]
11. Knowledge Aims / B. Certain Knowledge / 3. Fallibilism
Fallibilism is consistent with dogmatism or scepticism, and is not alternative to them [Dougherty]
It is best to see the fallibility in the reasons, rather than in the agents or the knowledge [Dougherty]
We can't normally say that we know something 'but it might be false' [Dougherty]