Combining Texts

All the ideas for '', 'Action' and 'On Formally Undecidable Propositions'

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37 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 / A. Overview of Logic / 1. Overview of Logic
If a sound conclusion comes from two errors that cancel out, the path of the argument must matter [Rumfitt]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
Standardly 'and' and 'but' are held to have the same sense by having the same truth table [Rumfitt]
The sense of a connective comes from primitively obvious rules of inference [Rumfitt]
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]
19. Language / F. Communication / 3. Denial
We learn 'not' along with affirmation, by learning to either affirm or deny a sentence [Rumfitt]
20. Action / A. Definition of Action / 1. Action Theory
Actions include: the involuntary, the purposeful, the intentional, and the self-consciously autonomous [Wilson/Schpall]
20. Action / A. Definition of Action / 4. Action as Movement
Maybe bodily movements are not actions, but only part of an agent's action of moving [Wilson/Schpall]
Is the action the arm movement, the whole causal process, or just the trying to do it? [Wilson/Schpall]
20. Action / B. Preliminaries of Action / 1. Intention to Act / a. Nature of intentions
To be intentional, an action must succeed in the manner in which it was planned [Wilson/Schpall]
If someone believes they can control the lottery, and then wins, the relevant skill is missing [Wilson/Schpall]
We might intend two ways to acting, knowing only one of them can succeed [Wilson/Schpall]
20. Action / B. Preliminaries of Action / 1. Intention to Act / c. Reducing intentions
On one model, an intention is belief-desire states, and intentional actions relate to beliefs and desires [Wilson/Schpall]
20. Action / B. Preliminaries of Action / 1. Intention to Act / d. Group intentions
Groups may act for reasons held by none of the members, so maybe groups are agents [Wilson/Schpall]
If there are shared obligations and intentions, we may need a primitive notion of 'joint commitment' [Wilson/Schpall]
20. Action / C. Motives for Action / 2. Acting on Beliefs / b. Action cognitivism
Strong Cognitivism identifies an intention to act with a belief [Wilson/Schpall]
Weak Cognitivism says intentions are only partly constituted by a belief [Wilson/Schpall]
Strong Cognitivism implies a mode of 'practical' knowledge, not based on observation [Wilson/Schpall]
20. Action / C. Motives for Action / 3. Acting on Reason / b. Intellectualism
Maybe the explanation of an action is in the reasons that make it intelligible to the agent [Wilson/Schpall]
20. Action / C. Motives for Action / 3. Acting on Reason / c. Reasons as causes
Causalists allow purposive explanations, but then reduce the purpose to the action's cause [Wilson/Schpall]
It is generally assumed that reason explanations are causal [Wilson/Schpall]