your walking out of your kitchen and you bump into something tall and hard, you look up and nothing is there, you get up in confusion and continued your day. Later that day you walk into your bathroom and see that the water turns on, you open the curtains and nothing is there so you turn the water off, you hear a voice from next to you. “Hey, what are you doing? I just turned that on!” you turned around and nothing is there “Oops- you can’t see me! Hah! Now out of my way! I need to shower!”