Combining Texts

All the ideas for 'Dissoi Logoi - on Double Arguments', 'Investigations in the Foundations of Set Theory I' and 'Law and Authority'

expand these ideas     |    start again     |     specify just one area for these texts


24 ideas

2. Reason / D. Definition / 8. Impredicative Definition
Predicative definitions are acceptable in mathematics if they distinguish objects, rather than creating them? [Zermelo, by Lavine]
3. Truth / H. Deflationary Truth / 2. Deflationary Truth
True and false statements can use exactly the same words [Anon (Diss)]
4. Formal Logic / F. Set Theory ST / 1. Set Theory
We take set theory as given, and retain everything valuable, while avoiding contradictions [Zermelo]
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
ZFC: Existence, Extension, Specification, Pairing, Unions, Powers, Infinity, Choice [Zermelo, by Clegg]
Zermelo published his axioms in 1908, to secure a controversial proof [Zermelo, by Maddy]
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
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
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
The Axiom of Separation requires set generation up to one step back from contradiction [Zermelo, by Maddy]
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
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
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
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
Different versions of set theory result in different underlying structures for numbers [Zermelo, by Brown,JR]
13. Knowledge Criteria / E. Relativism / 4. Cultural relativism
Thracians think tattooing adds to a girl's beauty, but elsewhere it is a punishment [Anon (Diss)]
Anything can be acceptable in some circumstances and unacceptable in others [Anon (Diss)]
Lydians prostitute their daughters to raise a dowery, but no Greek would marry such a girl [Anon (Diss)]
20. Action / C. Motives for Action / 3. Acting on Reason / b. Intellectualism
How could someone who knows everything fail to act correctly? [Anon (Diss)]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / j. Ethics by convention
Every apparent crime can be right in certain circumstances [Anon (Diss), by PG]
22. Metaethics / C. The Good / 1. Goodness / g. Consequentialism
It is right to lie to someone, to get them to take medicine they are reluctant to take [Anon (Diss)]
24. Political Theory / D. Ideologies / 5. Democracy / b. Consultation
The first priority in elections is to vote for people who support democracy [Anon (Diss)]
25. Social Practice / B. Equalities / 1. Grounds of equality
Only liberty, equality and sympathy can stand up to anti-social people [Kropotkin]
25. Social Practice / E. Policies / 5. Education / c. Teaching
We learn language, and we don't know who teaches us it [Anon (Diss)]