# Tagged Questions

**7**

votes

**1**answer

613 views

### Some constructive versions of the Continuum Hypothesis are false. Are any true, or open?

Background
In constructive set theory (say based on CZF) there are inequivalent ways of stating the continuum hypothesis. Some of them are easily if not trivially refutable with common anti-classical ...

**8**

votes

**3**answers

1k views

### Is set-induction relatively consistent?

One way to state the axiom of foundation is that the $\in$ relation on any transitive set is well-founded in the following sense:
A relation $(X,\prec)$ is well-founded if for any subset $S\subseteq ...

**8**

votes

**3**answers

820 views

### Intuitionistic Lowenheim-Skolem?

Is there a version of the Löwenheim-Skolem theorem in intuitionistic logic? I'm particularly interested in the "downward" form. The standard proof I know uses the Tarski-Vaught test for ...