There are two kinds of people in the world, those who believe there are two kinds of people in the world and those who don't. A block is always the same colour as itself. If one block is the same ...

Let $(X, \mathscr{B})$ be a standard Borel space, $R \subset X \times X$ an equivalence relation $\in \mathscr{B} \times \mathscr{B}$. Assume each equivalence class ...