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All the ideas for 'Reference and Definite Descriptions', 'Substitutional Classes and Relations' and 'What is Logic?'

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23 ideas

2. Reason / D. Definition / 3. Types of Definition
A decent modern definition should always imply a semantics [Hacking]
2. Reason / D. Definition / 7. Contextual Definition
Any linguistic expression may lack meaning when taken out of context [Russell]
2. Reason / F. Fallacies / 8. Category Mistake / a. Category mistakes
'The number one is bald' or 'the number one is fond of cream cheese' are meaningless [Russell]
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]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / p. Axiom of Reducibility
Axiom of Reducibility: there is always a function of the lowest possible order in a given level [Russell, by Bostock]
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 / F. Referring in Logic / 2. Descriptions / a. Descriptions
Russell only uses descriptions attributively, and Strawson only referentially [Donnellan, by Lycan]
5. Theory of Logic / F. Referring in Logic / 2. Descriptions / b. Definite descriptions
A definite description can have a non-referential use [Donnellan]
Definite descriptions are 'attributive' if they say something about x, and 'referential' if they pick x out [Donnellan]
'The x is F' only presumes that x exists; it does not actually entail the existence [Donnellan]
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 / A. Relations / 1. Nature of Relations
There is no complexity without relations, so no propositions, and no truth [Russell]
19. Language / B. Reference / 4. Descriptive Reference / b. Reference by description
A definite description 'the F' is referential if the speaker could thereby be referring to something not-F [Donnellan, by Sainsbury]
Donnellan is unclear whether the referential-attributive distinction is semantic or pragmatic [Bach on Donnellan]
A description can successfully refer, even if its application to the subject is not believed [Donnellan]
19. Language / B. Reference / 5. Speaker's Reference
Whether a definite description is referential or attributive depends on the speaker's intention [Donnellan]