Combining Texts

All the ideas for 'Classical Cosmology (frags)', 'On Formally Undecidable Propositions' and 'Introduction to Virtue Ethics'

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29 ideas

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]
17. Mind and Body / C. Functionalism / 2. Machine Functionalism
Basic logic can be done by syntax, with no semantics [Gödel, by Rey]
20. Action / C. Motives for Action / 4. Responsibility for Actions
We may still admire a person's character even if the traits are involuntary [Statman]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / d. Ethical theory
There is a new sort of moral scepticism, about the possibility of moral theories [Statman]
22. Metaethics / C. The Good / 2. Happiness / b. Eudaimonia
With a broad concept of flourishing, it might be possible without the virtues [Statman]
23. Ethics / C. Virtue Theory / 1. Virtue Theory / d. Virtue theory critique
Virtue theory isn't a genuine ethical theory, because it doesn't have universal application [Statman]
Promises create moral duties that have nothing to do with character [Statman]
23. Ethics / C. Virtue Theory / 2. Elements of Virtue Theory / d. Teaching virtue
Moral education is better by concrete example than abstract principle [Statman]
23. Ethics / C. Virtue Theory / 4. External Goods / d. Friendship
Friends express friendship even when no utility is involved [Statman]
23. Ethics / D. Deontological Ethics / 2. Duty
Behaviour may be disgusting or inhumane, but violate no duty [Statman]
The ancients recognised imperfect duties, but we have added perfect duties like justice [Statman]
25. Social Practice / F. Life Issues / 3. Abortion
Abortion issues focus on the mother's right over her body, and the status of the foetus [Statman]
27. Natural Reality / E. Cosmology / 1. Cosmology
Is the cosmos open or closed, mechanical or teleological, alive or inanimate, and created or eternal? [Robinson,TM, by PG]