Combining Texts

All the ideas for 'Against Coherence', 'Elements of Set Theory' and 'Formal and Material Consequence'

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21 ideas

4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / b. Terminology of ST
∈ says the whole set is in the other; ⊆ says the members of the subset are in the other [Enderton]
The 'ordered pair' <x,y> is defined to be {{x}, {x,y}} [Enderton]
A 'linear or total ordering' must be transitive and satisfy trichotomy [Enderton]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
Note that {Φ} =/= Φ, because Φ ∈ {Φ} but Φ ∉ Φ [Enderton]
The empty set may look pointless, but many sets can be constructed from it [Enderton]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / c. Unit (Singleton) Sets
The singleton is defined using the pairing axiom (as {x,x}) [Enderton]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / h. Axiom of Replacement VII
Fraenkel added Replacement, to give a theory of ordinal numbers [Enderton]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
We can only define functions if Choice tells us which items are involved [Enderton]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
If logic is topic-neutral that means it delves into all subjects, rather than having a pure subject matter [Read]
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
Not all arguments are valid because of form; validity is just true premises and false conclusion being impossible [Read]
If the logic of 'taller of' rests just on meaning, then logic may be the study of merely formal consequence [Read]
Maybe arguments are only valid when suppressed premises are all stated - but why? [Read]
5. Theory of Logic / B. Logical Consequence / 5. Modus Ponens
In modus ponens the 'if-then' premise contributes nothing if the conclusion follows anyway [Read]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
Logical connectives contain no information, but just record combination relations between facts [Read]
10. Modality / B. Possibility / 8. Conditionals / d. Non-truthfunction conditionals
Conditionals are just a shorthand for some proof, leaving out the details [Read]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / a. Coherence as justification
Incoherence may be more important for enquiry than coherence [Olsson]
Coherence is the capacity to answer objections [Olsson]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / c. Coherentism critique
Mere agreement of testimonies is not enough to make truth very likely [Olsson]
Coherence is only needed if the information sources are not fully reliable [Olsson]
A purely coherent theory cannot be true of the world without some contact with the world [Olsson]
Extending a system makes it less probable, so extending coherence can't make it more probable [Olsson]