Combining Texts

All the ideas for 'Walking the Tightrope of Reason', 'Questions on Aristotle's Physics' and 'On Formally Undecidable Propositions'

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44 ideas

1. Philosophy / D. Nature of Philosophy / 7. Despair over Philosophy
Philosophy may never find foundations, and may undermine our lives in the process [Fogelin]
2. Reason / A. Nature of Reason / 1. On Reason
Rationality is threatened by fear of inconsistency, illusions of absolutes or relativism, and doubt [Fogelin]
2. Reason / A. Nature of Reason / 9. Limits of Reason
Humans may never be able to attain a world view which is both rich and consistent [Fogelin]
A game can be played, despite having inconsistent rules [Fogelin]
2. Reason / B. Laws of Thought / 1. Laws of Thought
The law of noncontradiction is traditionally the most basic principle of rationality [Fogelin]
2. Reason / B. Laws of Thought / 3. Non-Contradiction
The law of noncontradiction makes the distinction between asserting something and denying it [Fogelin]
2. Reason / E. Argument / 3. Analogy
Legal reasoning is analogical, not deductive [Fogelin]
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]
9. Objects / C. Structure of Objects / 4. Quantity of an Object
Without magnitude a thing would retain its parts, but they would have no location [Buridan]
9. Objects / E. Objects over Time / 8. Continuity of Rivers
A thing is (less properly) the same over time if each part is succeeded by another [Buridan]
10. Modality / C. Sources of Modality / 3. Necessity by Convention
Conventions can only work if they are based on something non-conventional [Fogelin]
12. Knowledge Sources / C. Rationalism / 1. Rationalism
My view is 'circumspect rationalism' - that only our intellect can comprehend the world [Fogelin]
13. Knowledge Criteria / A. Justification Problems / 1. Justification / c. Defeasibility
Knowledge is legitimate only if all relevant defeaters have been eliminated [Fogelin]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / a. Coherence as justification
For coherentists, circularity is acceptable if the circle is large, rich and coherent [Fogelin]
13. Knowledge Criteria / C. External Justification / 6. Contextual Justification / a. Contextualism
A rule of justification might be: don't raise the level of scrutiny without a good reason [Fogelin]
13. Knowledge Criteria / D. Scepticism / 2. Types of Scepticism
Scepticism is cartesian (sceptical scenarios), or Humean (future), or Pyrrhonian (suspend belief) [Fogelin]
13. Knowledge Criteria / D. Scepticism / 6. Scepticism Critique
Scepticism deals in remote possibilities that are ineliminable and set the standard very high [Fogelin]
13. Knowledge Criteria / E. Relativism / 1. Relativism
Radical perspectivism replaces Kant's necessary scheme with many different schemes [Fogelin]
14. Science / A. Basis of Science / 2. Demonstration
Induction is not demonstration, because not all of the instances can be observed [Buridan]
14. Science / C. Induction / 2. Aims of Induction
Science is based on induction, for general truths about fire, rhubarb and magnets [Buridan]
17. Mind and Body / C. Functionalism / 2. Machine Functionalism
Basic logic can be done by syntax, with no semantics [Gödel, by Rey]
18. Thought / A. Modes of Thought / 5. Rationality / b. Human rationality
We are also irrational, with a unique ability to believe in bizarre self-created fictions [Fogelin]
21. Aesthetics / A. Aesthetic Experience / 3. Taste
Critics must be causally entangled with their subject matter [Fogelin]
21. Aesthetics / A. Aesthetic Experience / 4. Beauty
The word 'beautiful', when deprived of context, is nearly contentless [Fogelin]
21. Aesthetics / C. Artistic Issues / 5. Objectivism in Art
Saying 'It's all a matter to taste' ignores the properties of the object discussed [Fogelin]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / e. Human nature
Cynics are committed to morality, but disappointed or disgusted by human failings [Fogelin]
25. Social Practice / D. Justice / 3. Punishment / a. Right to punish
Deterrence, prevention, rehabilitation and retribution can come into conflict in punishments [Fogelin]
Retributivists say a crime can be 'paid for'; deterrentists still worry about potential victims [Fogelin]