Combining Texts

All the ideas for 'works', 'Elements of Set Theory' and 'General Draft'

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18 ideas

1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / a. Philosophy as worldly
Philosophy is homesickness - the urge to be at home everywhere [Novalis]
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]
12. Knowledge Sources / B. Perception / 1. Perception
Our images of bodies are not produced by the bodies, but by our own minds [Augustine, by Aquinas]
12. Knowledge Sources / C. Rationalism / 1. Rationalism
Our minds grasp reality by direct illumination (rather than abstraction from experience) [Augustine, by Matthews]
15. Nature of Minds / C. Capacities of Minds / 6. Idealisation
Desire for perfection is an illness, if it turns against what is imperfect [Novalis]
20. Action / B. Preliminaries of Action / 2. Willed Action / a. Will to Act
Augustine created the modern concept of the will [Augustine, by Matthews]
22. Metaethics / B. Value / 2. Values / g. Love
Love, and do what you will [Augustine]
22. Metaethics / C. The Good / 1. Goodness / b. Types of good
Pagans produced three hundred definitions of the highest good [Augustine, by Grayling]
23. Ethics / D. Deontological Ethics / 2. Duty
Augustine said (unusually) that 'ought' does not imply 'can' [Augustine, by Matthews]
29. Religion / B. Monotheistic Religion / 4. Christianity / d. Heresy
Augustine identified Donatism, Pelagianism and Manicheism as the main heresies [Augustine, by Matthews]
29. Religion / D. Religious Issues / 3. Problem of Evil / b. Human Evil
Augustine said evil does not really exist, and evil is a limitation in goodness [Augustine, by Perkins]