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All the ideas for 'Lectures on Ethics', 'Principia Ethica' and 'Which Logic is the Right Logic?'

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31 ideas

4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
The axiom of choice now seems acceptable and obvious (if it is meaningful) [Tharp]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
Logic is either for demonstration, or for characterizing structures [Tharp]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
Elementary logic is complete, but cannot capture mathematics [Tharp]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Second-order logic isn't provable, but will express set-theory and classic problems [Tharp]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / b. Basic connectives
In sentential logic there is a simple proof that all truth functions can be reduced to 'not' and 'and' [Tharp]
5. Theory of Logic / G. Quantification / 2. Domain of Quantification
The main quantifiers extend 'and' and 'or' to infinite domains [Tharp]
5. Theory of Logic / G. Quantification / 7. Unorthodox Quantification
There are at least five unorthodox quantifiers that could be used [Tharp]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
Skolem mistakenly inferred that Cantor's conceptions were illusory [Tharp]
The Löwenheim-Skolem property is a limitation (e.g. can't say there are uncountably many reals) [Tharp]
5. Theory of Logic / K. Features of Logics / 3. Soundness
Soundness would seem to be an essential requirement of a proof procedure [Tharp]
5. Theory of Logic / K. Features of Logics / 4. Completeness
Completeness and compactness together give axiomatizability [Tharp]
5. Theory of Logic / K. Features of Logics / 5. Incompleteness
If completeness fails there is no algorithm to list the valid formulas [Tharp]
5. Theory of Logic / K. Features of Logics / 6. Compactness
Compactness is important for major theories which have infinitely many axioms [Tharp]
Compactness blocks infinite expansion, and admits non-standard models [Tharp]
5. Theory of Logic / K. Features of Logics / 8. Enumerability
A complete logic has an effective enumeration of the valid formulas [Tharp]
Effective enumeration might be proved but not specified, so it won't guarantee knowledge [Tharp]
21. Aesthetics / A. Aesthetic Experience / 4. Beauty
The beautiful is whatever it is intrinsically good to admire [Moore,GE]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / b. Defining ethics
Moore tries to show that 'good' is indefinable, but doesn't understand what a definition is [MacIntyre on Moore,GE]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / a. Idealistic ethics
The Open Question argument leads to anti-realism and the fact-value distinction [Boulter on Moore,GE]
The naturalistic fallacy claims that natural qualties can define 'good' [Moore,GE]
Moore cannot show why something being good gives us a reason for action [MacIntyre on Moore,GE]
Can learning to recognise a good friend help us to recognise a good watch? [MacIntyre on Moore,GE]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / c. Ethical intuitionism
Moore's combination of antinaturalism with strong supervenience on the natural is incoherent [Hanna on Moore,GE]
Despite Moore's caution, non-naturalists incline towards intuitionism [Moore,GE, by Smith,M]
22. Metaethics / B. Value / 1. Nature of Value / c. Objective value
We should ask what we would judge to be good if it existed in absolute isolation [Moore,GE]
22. Metaethics / C. The Good / 1. Goodness / a. Form of the Good
It is always an open question whether anything that is natural is good [Moore,GE]
22. Metaethics / C. The Good / 1. Goodness / b. Types of good
The three main values are good, right and beauty [Moore,GE, by Ross]
22. Metaethics / C. The Good / 1. Goodness / c. Right and good
For Moore, 'right' is what produces good [Moore,GE, by Ross]
'Right' means 'cause of good result' (hence 'useful'), so the end does justify the means [Moore,GE]
23. Ethics / E. Utilitarianism / 1. Utilitarianism
Relationships imply duties to people, not merely the obligation to benefit them [Ross on Moore,GE]
25. Social Practice / F. Life Issues / 4. Suicide
The maxim for suicide is committed to the value of life, and is thus contradictory [Kant]