This continuous function never takes on this value as we go from X equaling A to X equal B. Let's see if I can draw that. Let's see if I can get from here to here without ever essentially crossing this dotted line. Well, let's see, I could, ooh, maybe I'll avoid it a little bit. I'll avoid, but gee, how am I going to get there? Well, without picking up my pencil. Well, I really need to cross that line.