Combining Texts

All the ideas for 'Does Emp.Knowledge have Foundation?', 'The Birth of Tragedy' and 'Elements of Set Theory'

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12 ideas

1. Philosophy / D. Nature of Philosophy / 1. Philosophy
Philosophy begins in the horror and absurdity of existence [Nietzsche, by Ansell Pearson]
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]
A 'linear or total ordering' must be transitive and satisfy trichotomy [Enderton]
The 'ordered pair' <x,y> is defined to be {{x}, {x,y}} [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]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / c. Empirical foundations
If observation is knowledge, it is not just an experience; it is a justification in the space of reasons [Sellars]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / f. Foundationalism critique
Observations like 'this is green' presuppose truths about what is a reliable symptom of what [Sellars]
18. Thought / D. Concepts / 4. Structure of Concepts / f. Theory theory of concepts
The concept of 'green' involves a battery of other concepts [Sellars]