Combining Philosophers

All the ideas for Aeschylus, Gerhard Gentzen and Donald C. Williams

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10 ideas

5. Theory of Logic / A. Overview of Logic / 2. History of Logic
11022 Gentzen introduced a natural deduction calculus (NK) in 1934 [Gentzen, by Read]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
11065 The inferential role of a logical constant constitutes its meaning [Gentzen, by Hanna]
11023 The logical connectives are 'defined' by their introduction rules [Gentzen]
11213 Each logical symbol has an 'introduction' rule to define it, and hence an 'elimination' rule [Gentzen]
5. Theory of Logic / H. Proof Systems / 4. Natural Deduction
13832 Natural deduction shows the heart of reasoning (and sequent calculus is just a tool) [Gentzen, by Hacking]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / g. Incompleteness of Arithmetic
10067 Gentzen proved the consistency of arithmetic from assumptions beyond arithmetic [Gentzen, by Musgrave]
8. Modes of Existence / B. Properties / 13. Tropes / a. Nature of tropes
8510 'Socrates is wise' means a concurrence sum contains a member of a similarity set [Williams,DC]
8508 A 'trope' is an abstract particular, the occurrence of an essence [Williams,DC]
8509 A world is completely constituted by its tropes and their connections [Williams,DC]
25. Social Practice / D. Justice / 2. The Law / b. Rule of law
7810 The 'Eumenides' of Aeschylus shows blood feuds replaced by law [Aeschylus, by Grayling]