If you look, you cannot see me. And if you see me, you cannot see anything else. I can make anything you want happen, but later everything goes back to normal. What am I?
If all Wibbles are Criggles, all Borkins are Kwumblins, no Hoggles are Borkins, and all Criggles are Borkins, is it true that all Borkins are Criggles?