We look a thing, can we see it directly? We touch a thing, can we touch it directly? The answer is none. There is a medium between our eyes and a thing , between our hands and a thing. It is like very clearly 3D monitor. Namely, we use simulation system in a body. So, we can’t touch and look directly. Then, we think a thing is this position, really is a thing is not this position. We can’t look substance. We usually look shadow of substance. Yes, substance exist different position.