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All the ideas for 'Laches', 'Convergence' and 'On Formally Undecidable Propositions'

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31 ideas

1. Philosophy / A. Wisdom / 3. Wisdom Deflated
Don't assume that wisdom is the automatic consequence of old age [Plato]
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]
15. Nature of Minds / C. Capacities of Minds / 1. Faculties
There are 23 core brain functions, with known circuit, transmitters, genes and behaviour [Watson]
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 / E. Mind as Physical / 1. Physical Mind
Traditional ideas of the mind were weakened in the 1950s by mind-influencing drugs [Watson]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / e. Human nature
Humans have been hunter-gatherers for 99.5% of their existence [Watson]
23. Ethics / C. Virtue Theory / 3. Virtues / d. Courage
Being unafraid (perhaps through ignorance) and being brave are two different things [Plato]
26. Natural Theory / C. Causation / 7. Eliminating causation
The Uncertainty Principle implies that cause and effect can't be measured [Watson]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / a. Electrodynamics
The interference of light through two slits confirmed that it is waves [Watson]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / c. Electrons
Electrons rotate in hyrogen atoms 10^13 times per second [Watson]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / d. Quantum mechanics
Quantum theory explains why nature is made up of units, such as elements [Watson]
27. Natural Reality / B. Modern Physics / 4. Standard Model / a. Concept of matter
Only four particles are needed for matter: up and down quark, electron, electron-neutrino [Watson]
27. Natural Reality / F. Chemistry / 1. Chemistry
The shape of molecules is important, as well as the atoms and their bonds [Watson]
27. Natural Reality / G. Biology / 2. Life
In 1828 the animal substance urea was manufactured from inorganic ingredients [Watson]
Information is physical, and living can be seen as replicating and preserving information [Watson]