Combining Texts

All the ideas for 'Realism in Mathematics', 'Elements of Set Theory' and 'Equality and Partiality'

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19 ideas

4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / b. Terminology of ST
13201 ∈ says the whole set is in the other; ⊆ says the members of the subset are in the other [Enderton]
13204 The 'ordered pair' <x,y> is defined to be {{x}, {x,y}} [Enderton]
13206 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
13200 Note that {Φ} =/= Φ, because Φ ∈ {Φ} but Φ ∉ Φ [Enderton]
13199 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
13203 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
13202 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
13205 We can only define functions if Choice tells us which items are involved [Enderton]
4. Formal Logic / F. Set Theory ST / 7. Natural Sets
8755 Maddy replaces pure sets with just objects and perceived sets of objects [Maddy, by Shapiro]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
10718 A natural number is a property of sets [Maddy, by Oliver]
6. Mathematics / C. Sources of Mathematics / 2. Intuition of Mathematics
8756 Intuition doesn't support much mathematics, and we should question its reliability [Maddy, by Shapiro]
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / a. Mathematical empiricism
17733 We know mind-independent mathematical truths through sets, which rest on experience [Maddy, by Jenkins]
20. Action / C. Motives for Action / 5. Action Dilemmas / c. Omissions
6479 Noninterference requires justification as much as interference does [Nagel]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / a. Preconditions for ethics
6450 Morality must be motivating, and not because of pre-moral motives [Nagel]
23. Ethics / B. Contract Ethics / 6. Game Theory
6447 Game theory misses out the motivation arising from the impersonal standpoint [Nagel]
23. Ethics / D. Deontological Ethics / 3. Universalisability
6446 In ethics we abstract from our identity, but not from our humanity [Nagel]
23. Ethics / D. Deontological Ethics / 4. Categorical Imperative
6477 I can only universalise a maxim if everyone else could also universalise it [Nagel]
24. Political Theory / D. Ideologies / 6. Liberalism / c. Liberal equality
6448 A legitimate system is one accepted as both impartial and reasonably partial [Nagel]
25. Social Practice / B. Equalities / 2. Political equality
6478 Democracy is opposed to equality, if the poor are not a majority [Nagel]