Combining Texts

All the ideas for 'works', 'The Problem of Empty Names' and 'A Note on the entscheidungsproblem'

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4 ideas

4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
Zermelo made 'set' and 'member' undefined axioms [Zermelo, by Chihara]
For Zermelo's set theory the empty set is zero and the successor of each number is its unit set [Zermelo, by Blackburn]
5. Theory of Logic / F. Referring in Logic / 1. Naming / e. Empty names
Unreflectively, we all assume there are nonexistents, and we can refer to them [Reimer]
5. Theory of Logic / K. Features of Logics / 7. Decidability
Validity is provable, but invalidity isn't, because the model is infinite [Church, by McGee]