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All the ideas for 'Mahaprajnaparamitashastra', 'works' and 'Nietzsche's Immoralism'

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8 ideas

5. Theory of Logic / A. Overview of Logic / 2. History of Logic
Gentzen introduced a natural deduction calculus (NK) in 1934 [Gentzen, by Read]
     Full Idea: Gentzen introduced a natural deduction calculus (NK) in 1934.
     From: report of Gerhard Gentzen (works [1938]) by Stephen Read - Thinking About Logic Ch.8
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
The inferential role of a logical constant constitutes its meaning [Gentzen, by Hanna]
     Full Idea: Gentzen argued that the inferential role of a logical constant constitutes its meaning.
     From: report of Gerhard Gentzen (works [1938]) by Robert Hanna - Rationality and Logic 5.3
     A reaction: Possibly inspired by Wittgenstein's theory of meaning as use? This idea was the target of Prior's famous connective 'tonk', which has the role of implying anything you like, proving sentences which are not logical consequences.
The logical connectives are 'defined' by their introduction rules [Gentzen]
     Full Idea: The introduction rules represent, as it were, the 'definitions' of the symbols concerned, and the elimination rules are no more, in the final analysis, than the consequences of these definitions.
     From: Gerhard Gentzen (works [1938]), quoted by Stephen Read - Thinking About Logic Ch.8
     A reaction: If an introduction-rule (or a truth table) were taken as fixed and beyond dispute, then it would have the status of a definition, since there would be nothing else to appeal to. So is there anything else to appeal to here?
Each logical symbol has an 'introduction' rule to define it, and hence an 'elimination' rule [Gentzen]
     Full Idea: To every logical symbol there belongs precisely one inference figure which 'introduces' the symbol ..and one which 'eliminates' it. The introductions represent the 'definitions' of the symbols concerned, and eliminations are consequences of these.
     From: Gerhard Gentzen (works [1938], II.5.13), quoted by Ian Rumfitt - "Yes" and "No" III
     A reaction: [1935 paper] This passage is famous, in laying down the basics of natural deduction systems of logic (ones using only rules, and avoiding axioms). Rumfitt questions whether Gentzen's account gives the sense of the connectives.
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / g. Incompleteness of Arithmetic
Gentzen proved the consistency of arithmetic from assumptions beyond arithmetic [Gentzen, by Musgrave]
     Full Idea: Gentzen proved the consistency of arithmetic from assumptions which transcend arithmetic.
     From: report of Gerhard Gentzen (works [1938]) by Alan Musgrave - Logicism Revisited §5
     A reaction: This does not contradict Gödel's famous result, but reinforces it. The interesting question is what assumptions Gentzen felt he had to make.
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / g. Moral responsibility
Unlike aesthetic evaluation, moral evaluation needs a concept of responsibility [Foot]
     Full Idea: Moral, as opposed to aesthetic, evaluation does require some distinction between actions for which we are responsible and those for which we are not responsible.
     From: Philippa Foot (Nietzsche's Immoralism [1991], p.154)
     A reaction: It is hard to disagree with this, but difficult to give a precise account of responsibility, probably because it is not an all-or-nothing matter. If we accept responsibility for our controlled actions, why not for our considered aesthetic judgements?
23. Ethics / C. Virtue Theory / 3. Virtues / a. Virtues
The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna]
     Full Idea: The six perfections are of giving, morality, patience, vigour, meditation, and wisdom.
     From: Nagarjuna (Mahaprajnaparamitashastra [c.120], 88)
     A reaction: What is 'morality', if giving is not part of it? I like patience and vigour being two of the virtues, which immediately implies an Aristotelian mean (which is always what is 'appropriate').
23. Ethics / C. Virtue Theory / 3. Virtues / c. Justice
The practice of justice may well need a recognition of human equality [Foot]
     Full Idea: I wonder whether the practice of justice may not absolutely require a certain recognition of equality between human beings, not a pretence of the equality of talents, but something deeper.
     From: Philippa Foot (Nietzsche's Immoralism [1991], p.152)
     A reaction: {My 'something deeper' is expressed by Foot in a quotation from Gertrude Stein]. This may well be the most fundamental division which runs across a society - between those who accept and those reject human equality.