Combining Texts

All the ideas for 'fragments/reports', 'On Formally Undecidable Propositions' and 'On Propositions: What they are, and Meaning'

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28 ideas

3. Truth / A. Truth Problems / 5. Truth Bearers
In its primary and formal sense, 'true' applies to propositions, not beliefs [Russell]
3. Truth / B. Truthmakers / 1. For Truthmakers
The truth or falsehood of a belief depends upon a fact to which the belief 'refers' [Russell]
3. Truth / C. Correspondence Truth / 1. Correspondence Truth
Propositions of existence, generalities, disjunctions and hypotheticals make correspondence tricky [Russell]
3. Truth / F. Semantic Truth / 1. Tarski's Truth / a. Tarski's truth definition
Prior to Gödel we thought truth in mathematics consisted in provability [Gödel, by Quine]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
Gödel show that the incompleteness of set theory was a necessity [Gödel, by Hallett,M]
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
The limitations of axiomatisation were revealed by the incompleteness theorems [Gödel, by Koellner]
5. Theory of Logic / K. Features of Logics / 2. Consistency
Second Incompleteness: nice theories can't prove their own consistency [Gödel, by Smith,P]
5. Theory of Logic / K. Features of Logics / 3. Soundness
If soundness can't be proved internally, 'reflection principles' can be added to assert soundness [Gödel, by Halbach/Leigh]
5. Theory of Logic / K. Features of Logics / 5. Incompleteness
Gödel's First Theorem sabotages logicism, and the Second sabotages Hilbert's Programme [Smith,P on Gödel]
The undecidable sentence can be decided at a 'higher' level in the system [Gödel]
6. Mathematics / A. Nature of Mathematics / 1. Mathematics
There can be no single consistent theory from which all mathematical truths can be derived [Gödel, by George/Velleman]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / g. Incompleteness of Arithmetic
Gödel showed that arithmetic is either incomplete or inconsistent [Gödel, by Rey]
First Incompleteness: arithmetic must always be incomplete [Gödel, by Smith,P]
Arithmetical truth cannot be fully and formally derived from axioms and inference rules [Gödel, by Nagel/Newman]
Gödel's Second says that semantic consequence outruns provability [Gödel, by Hanna]
First Incompleteness: a decent consistent system is syntactically incomplete [Gödel, by George/Velleman]
Second Incompleteness: a decent consistent system can't prove its own consistency [Gödel, by George/Velleman]
There is a sentence which a theory can show is true iff it is unprovable [Gödel, by Smith,P]
'This system can't prove this statement' makes it unprovable either way [Gödel, by Clegg]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / d. Predicativism
Realists are happy with impredicative definitions, which describe entities in terms of other existing entities [Gödel, by Shapiro]
11. Knowledge Aims / A. Knowledge / 4. Belief / b. Elements of beliefs
The three questions about belief are its contents, its success, and its character [Russell]
17. Mind and Body / B. Behaviourism / 4. Behaviourism Critique
If we object to all data which is 'introspective' we will cease to believe in toothaches [Russell]
17. Mind and Body / C. Functionalism / 2. Machine Functionalism
Basic logic can be done by syntax, with no semantics [Gödel, by Rey]
17. Mind and Body / D. Property Dualism / 3. Property Dualism
There are distinct sets of psychological and physical causal laws [Russell]
19. Language / D. Propositions / 1. Propositions
Our important beliefs all, if put into words, take the form of propositions [Russell]
A proposition expressed in words is a 'word-proposition', and one of images an 'image-proposition' [Russell]
A proposition is what we believe when we believe truly or falsely [Russell]
21. Aesthetics / C. Artistic Issues / 7. Art and Morality
Musical performance can reveal a range of virtues [Damon of Ath.]