Combining Texts

All the ideas for 'fragments/reports', 'Investigations in the Foundations of Set Theory I' and 'An Outline of Philosophy'

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25 ideas

2. Reason / D. Definition / 8. Impredicative Definition
15924 Predicative definitions are acceptable in mathematics if they distinguish objects, rather than creating them? [Zermelo, by Lavine]
4. Formal Logic / F. Set Theory ST / 1. Set Theory
17608 We take set theory as given, and retain everything valuable, while avoiding contradictions [Zermelo]
17607 Set theory investigates number, order and function, showing logical foundations for mathematics [Zermelo]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
10870 ZFC: Existence, Extension, Specification, Pairing, Unions, Powers, Infinity, Choice [Zermelo, by Clegg]
13012 Zermelo published his axioms in 1908, to secure a controversial proof [Zermelo, by Maddy]
17609 Set theory can be reduced to a few definitions and seven independent axioms [Zermelo]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / c. Axiom of Pairing II
13017 Zermelo introduced Pairing in 1930, and it seems fairly obvious [Zermelo, by Maddy]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / i. Axiom of Foundation VIII
13015 Zermelo used Foundation to block paradox, but then decided that only Separation was needed [Zermelo, by Maddy]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / m. Axiom of Separation
13020 The Axiom of Separation requires set generation up to one step back from contradiction [Zermelo, by Maddy]
13486 Not every predicate has an extension, but Separation picks the members that satisfy a predicate [Zermelo, by Hart,WD]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
13487 In ZF, the Burali-Forti Paradox proves that there is no set of all ordinals [Zermelo, by Hart,WD]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / f. Zermelo numbers
18178 For Zermelo the successor of n is {n} (rather than n U {n}) [Zermelo, by Maddy]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
13027 Zermelo believed, and Von Neumann seemed to confirm, that numbers are sets [Zermelo, by Maddy]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / e. Structuralism critique
9627 Different versions of set theory result in different underlying structures for numbers [Zermelo, by Brown,JR]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / d. Ethical theory
21740 I doubt whether ethics is part of philosophy [Russell]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / h. Expressivism
21741 'You ought to do p' primarily has emotional content, expressing approval [Russell]
22. Metaethics / B. Value / 2. Values / g. Love
21746 Unlike hate, all desires can be satisfied by love [Russell]
22. Metaethics / C. The Good / 1. Goodness / b. Types of good
21747 Goodness is a combination of love and knowledge [Russell]
22. Metaethics / C. The Good / 2. Happiness / d. Routes to happiness
21743 In wartime, happiness is hating the enemy, because it gives the war a purpose [Russell]
23. Ethics / C. Virtue Theory / 1. Virtue Theory / b. Basis of virtue
21742 Originally virtue was obedience, to gods, government, or custom [Russell]
23. Ethics / D. Deontological Ethics / 4. Categorical Imperative
21745 Act so as to produce harmonious rather than discordant desires [Russell]
25. Social Practice / D. Justice / 3. Punishment / d. Reform of offenders
21744 Legally curbing people's desires is inferior to improving their desires [Russell]
26. Natural Theory / A. Speculations on Nature / 5. Infinite in Nature
1748 Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius]
27. Natural Reality / D. Time / 3. Parts of Time / e. Present moment
22891 We could be aware of time if senses briefly vibrated, extending their experience of movement [Russell, by Bardon]
27. Natural Reality / G. Biology / 3. Evolution
5989 Archelaus said life began in a primeval slime [Archelaus, by Schofield]