Combining Texts

All the ideas for 'reports', 'Reflections on Value' and 'Elements of Set Theory'

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15 ideas

1. Philosophy / D. Nature of Philosophy / 3. Philosophy Defined
All thought about values is philosophical, and thought about anything else is not philosophy [Weil]
1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / b. Philosophy as transcendent
Philosophy aims to change the soul, not to accumulate knowledge [Weil]
1. Philosophy / E. Nature of Metaphysics / 3. Metaphysical Systems
Systems are not unique to each philosopher. The platonist tradition is old and continuous [Weil]
3. Truth / A. Truth Problems / 1. Truth
Truth is a value of thought [Weil]
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]
10. Modality / A. Necessity / 8. Transcendental Necessity
Even the gods cannot strive against necessity [Pittacus, by Diog. Laertius]
22. Metaethics / B. Value / 1. Nature of Value / e. Means and ends
Ends, unlike means, cannot be defined, which is why people tend to pursue means [Weil]
22. Metaethics / B. Value / 2. Values / a. Normativity
Minds essentially and always strive towards value [Weil]