# Questions tagged [lo.logic]

first-order and higher-order logic, model theory, set theory, proof theory, computability theory, formal languages, definability, interplay of syntax and semantics, constructive logic, intuitionism, philosophical logic, modal logic, completeness, Gödel incompleteness, decidability, undecidability, theories of truth, truth revision, consistency.

**4**

**0**answers

### Order types of models of theories of ordinals

**0**

**0**answers

### Proof of consistency of proof system syntactically [on hold]

**5**

**1**answer

### Definability of the ring of integer in algebraic extensions of $\mathbb Q$

**0**

**0**answers

### McNaughton functions and hypersequents for Lukasiewicz logic

**3**

**1**answer

### Can power set axiom be proved in a class theory of well ordered hereditarily accessible sets?

**17**

**4**answers

### What do we gain with higher order logics?

**8**

**0**answers

### Monadic second-order theories of the reals

**-4**

**0**answers

### What form can have statements that are provable by the method of mathematical induction? [closed]

**1**

**0**answers

### Sentential, first order and higher logics from a categorical perspective

**0**

**0**answers

### Good texts (other than Kunen and Jech) on set theory, specifically on consistency proofs (reflection theorems, absoluteness, etc) [closed]

**22**

**9**answers

### Defining the standard model of PA so that a space alien could understand

**4**

**1**answer

### Turing independent refinement

**13**

**2**answers

### Is categoricity retained when reducing the language?

**18**

**2**answers

### Status of proof by contradiction and excluded middle throughout the history of mathematics?

**6**

**1**answer