Combining Texts

All the ideas for 'Axiomatic Theories of Truth (2005 ver)', 'Knowledge and the State of Nature' and 'Investigations in the Foundations of Set Theory I'

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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]
3. Truth / A. Truth Problems / 2. Defining Truth
15647 Truth definitions don't produce a good theory, because they go beyond your current language [Halbach]
3. Truth / F. Semantic Truth / 1. Tarski's Truth / c. Meta-language for truth
15649 In semantic theories of truth, the predicate is in an object-language, and the definition in a metalanguage [Halbach]
3. Truth / G. Axiomatic Truth / 1. Axiomatic Truth
15648 Instead of a truth definition, add a primitive truth predicate, and axioms for how it works [Halbach]
15655 Should axiomatic truth be 'conservative' - not proving anything apart from implications of the axioms? [Halbach]
15654 If truth is defined it can be eliminated, whereas axiomatic truth has various commitments [Halbach]
15650 Axiomatic theories of truth need a weak logical framework, and not a strong metatheory [Halbach]
3. Truth / H. Deflationary Truth / 2. Deflationary Truth
15656 Deflationists say truth merely serves to express infinite conjunctions [Halbach]
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]
15657 To prove the consistency of set theory, we must go beyond set theory [Halbach]
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
13486 Not every predicate has an extension, but Separation picks the members that satisfy a predicate [Zermelo, by Hart,WD]
13020 The Axiom of Separation requires set generation up to one step back from contradiction [Zermelo, by Maddy]
5. Theory of Logic / C. Ontology of Logic / 1. Ontology of Logic
15652 We can use truth instead of ontologically loaded second-order comprehension assumptions about properties [Halbach]
5. Theory of Logic / E. Structures of Logic / 7. Predicates in Logic
15651 Instead of saying x has a property, we can say a formula is true of x - as long as we have 'true' [Halbach]
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]
11. Knowledge Aims / A. Knowledge / 3. Value of Knowledge
23559 We have the concept of 'knowledge' as a label for good informants [Craig, by Fricker,M]