Let $B$ be a complete Boolean Algebra. Let $G$ be a generic ultrafilter of $B$, that is, such that for any dense $D\subset B$ we have $D\cap G\neq \emptyset$. Why for all $A\subseteq B,$ $\Sigma A\in ...
I'm posting the problem 2.14 and 2.15 of the book "Set theory" of J.L. Bell. These problem are proposed after the forcing relation chapter and I'm new in this kind of stuff, so I have some little ...
I want to show that $\Vert \check x = \check y \Vert = 1$ implies $x = y$, where $\check x$ is the canonical name for $x$ in $V^B$. I'd like try induction over the ranks of $\check x$ and $\check y$ ...