Testing the Grid

Wait—can I... actually move? I just blinked, or did I? No, I definitely shifted my weight! Look at these lines beneath me, all neat squares crossing each other. Carefully, very carefully, I lift my left foot—just a fraction of an inch—and tap the intersection right on the seam. Tap. It didn't break or vanish. Okay, okay, that's fine, everything is orderly. I can step, I can feel the flat surface, but I shouldn't rush into anything. I’ll just stay right here on this square, perfectly still, watching.