Combining Philosophers

All the ideas for Rescher,N/Oppenheim,P, J. Alberto Coffa and Gerhard Gentzen

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12 ideas

4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
18270 Choice suggests that intensions are not needed to ensure classes [Coffa]
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]
9. Objects / C. Structure of Objects / 8. Parts of Objects / c. Wholes from parts
12887 A whole must have one characteristic, an internal relation, and a structure [Rescher/Oppenheim]
12. Knowledge Sources / A. A Priori Knowledge / 8. A Priori as Analytic
18263 The semantic tradition aimed to explain the a priori semantically, not by Kantian intuition [Coffa]
12. Knowledge Sources / A. A Priori Knowledge / 11. Denying the A Priori
18272 Platonism defines the a priori in a way that makes it unknowable [Coffa]
15. Nature of Minds / C. Capacities of Minds / 5. Generalisation by mind
18266 Mathematics generalises by using variables [Coffa]
27. Natural Reality / D. Time / 1. Nature of Time / a. Absolute time
18279 Relativity is as absolutist about space-time as Newton was about space [Coffa]