Combining Texts

Ideas for 'fragments/reports', 'What is Logic?' and 'Three Grades of Modal Involvement'

expand these ideas     |    start again     |     choose another area for these texts

display all the ideas for this combination of texts

---

9 ideas

5. Theory of Logic / A. Overview of Logic / 4. Pure Logic

13845

The various logics are abstractions made from terms like 'if...then' in English [Hacking]

5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic

13840

First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking]

13844

A limitation of first-order logic is that it cannot handle branching quantifiers [Hacking]

5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic

13842

Second-order completeness seems to need intensional entities and possible worlds [Hacking]

5. Theory of Logic / C. Ontology of Logic / 1. Ontology of Logic

12219

Whether a modal claim is true depends on how the object is described [Quine, by Fine,K]

5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives

13837

With a pure notion of truth and consequence, the meanings of connectives are fixed syntactically [Hacking]

5. Theory of Logic / E. Structures of Logic / 4. Variables in Logic

13839

Perhaps variables could be dispensed with, by arrows joining places in the scope of quantifiers [Hacking]

5. Theory of Logic / G. Quantification / 1. Quantification

10922

Objects are the values of variables, so a referentially opaque context cannot be quantified into [Quine]

5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems

13843

If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking]