You look around your room, noting how your clothes are thrown about. You say, "Man, this room is a pig sty." As those words were spoken, the room began to change. The bed was replaced with a hay stack. The carpet changed to a mixture of hay and dirt, and a small mud pool formed in the corner of the room. The dresser became a feeding trough. The walls gave way and the roof raised up high on poles. Gates arose in place of the walls, creating a pen, over which were many other pens each with their own pig. As you said, your room is a pig sty, and so it is.
You blink a few times, taking in all the changes that just happened. Inside, you are quite stable. Surely, the change would shock anyone else, but you spoke the truth, something you knew and something that wasn't unexpected. By this reasoning, what just happened was perfectly logical. You survey your surroundings some more, and are provoked by something to speak aloud again.