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All the ideas for 'What is Logic?st1=Ian Hacking', 'works' and 'Locke on Human Understanding'

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19 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]
8. Modes of Existence / E. Nominalism / 2. Resemblance Nominalism
Two things can only resemble one another in some respect, and that may reintroduce a universal [Lowe]
9. Objects / B. Unity of Objects / 2. Substance / d. Substance defined
On substances, Leibniz emphasises unity, Spinoza independence, Locke relations to qualities [Lowe]
12. Knowledge Sources / B. Perception / 6. Inference in Perception
Perception is a mode of belief-acquisition, and does not involve sensation [Lowe]
12. Knowledge Sources / B. Perception / 7. Causal Perception
Science requires a causal theory - perception of an object must be an experience caused by the object [Lowe]
16. Persons / D. Continuity of the Self / 1. Identity and the Self
Personal identity is a problem across time (diachronic) and at an instant (synchronic) [Lowe]
17. Mind and Body / E. Mind as Physical / 7. Anti-Physicalism / a. Physicalism critique
Do new ideas increase the weight of the brain? [Dance]
18. Thought / B. Mechanics of Thought / 4. Language of Thought
Mentalese isn't a language, because it isn't conventional, or a means of public communication [Lowe]
19. Language / A. Nature of Meaning / 2. Meaning as Mental
If meaning is mental pictures, explain "the cat (or dog!) is NOT on the mat" [Lowe]