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All the ideas for 'What is Logic?st1=Ian Hacking', 'Things' and 'The Big Book of Concepts'

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36 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]
9. Objects / A. Existence of Objects / 2. Abstract Objects / c. Modern abstracta
Bodies, properties, relations, events, numbers, sets and propositions are 'things' if they exist [Lowe]
12. Knowledge Sources / B. Perception / 5. Interpretation
Research shows perceptual discrimination is sharper at category boundaries [Murphy]
14. Science / C. Induction / 1. Induction
Induction is said to just compare properties of categories, but the type of property also matters [Murphy]
18. Thought / D. Concepts / 1. Concepts / a. Nature of concepts
The main theories of concepts are exemplar, prototype and knowledge [Murphy]
18. Thought / D. Concepts / 4. Structure of Concepts / c. Classical concepts
The theoretical and practical definitions for the classical view are very hard to find [Murphy]
The classical definitional approach cannot distinguish typical and atypical category members [Murphy]
Classical concepts follow classical logic, but concepts in real life don't work that way [Murphy]
Classical concepts are transitive hierarchies, but actual categories may be intransitive [Murphy]
The classical core is meant to be the real concept, but actually seems unimportant [Murphy]
18. Thought / D. Concepts / 4. Structure of Concepts / d. Concepts as prototypes
There is no 'ideal' bird or dog, and prototypes give no information about variability [Murphy]
Prototypes are unified representations of the entire category (rather than of members) [Murphy]
The prototype theory uses observed features, but can't include their construction [Murphy]
The prototype theory handles hierarchical categories and combinations of concepts well [Murphy]
Prototypes theory of concepts is best, as a full description with weighted typical features [Murphy]
Learning concepts is forming prototypes with a knowledge structure [Murphy]
18. Thought / D. Concepts / 4. Structure of Concepts / e. Concepts from exemplars
The most popular theories of concepts are based on prototypes or exemplars [Murphy]
The exemplar view of concepts says 'dogs' is the set of dogs I remember [Murphy]
Exemplar theory struggles with hierarchical classification and with induction [Murphy]
Children using knowing and essentialist categories doesn't fit the exemplar view [Murphy]
Conceptual combination must be compositional, and can't be built up from exemplars [Murphy]
The concept of birds from exemplars must also be used in inductions about birds [Murphy]
18. Thought / D. Concepts / 4. Structure of Concepts / f. Theory theory of concepts
We do not learn concepts in isolation, but as an integrated part of broader knowledge [Murphy]
Concepts with familiar contents are easier to learn [Murphy]
Some knowledge is involved in instant use of categories, other knowledge in explanations [Murphy]
People categorise things consistent with their knowledge, even rejecting some good evidence [Murphy]