Recently I was watching the famous "Powers of Ten" video which starts with a couple at a picnic and moves out to the far edges of the universe, moving ten times further out each second. After this the camera goes back to the couple and enters the hand of the man at the picnic, moving through layers of skin, blood cells, molecules, atoms and finally a haze of interacting subatomic particles. What struck me about this part of the video is that if the camera was to move beyond the boundaries of the man's hand we wouldn't be able to tell. There is no demarcation between the subatomic particles which make up the man's hand and the subatomic particles which make up the surrounding air. So, in what sense do seperate entities exist? Is seperateness an illusion inherent to the experience of beings at a macroscopic scale, similar to our illusion that objects are "solid" when in reality an atom is comprised mostly of empty space?