Kotaku published recently an interesting article about a new way of thinking about a fourth dimension. We only live in 3 dimensions and, if we would see a 4D object we would only see its 3D imprint in our world. Things could simply pop in and out of existence as far we can be concerned.
In the video from above the presenter, one of the creators of MiegaKure, a game where you use a 4D space to solve puzzles, explains that you could get past a wall that cannot be crossed if you would be able to shift into the 4th dimension, then moving like you move in 3D, get past the wall, and then get back into the 3D world.
In this way you would disappear from this 3D world and then come back. Interesting philosophical point. Would that explain the fact that at quantum level particles pop in and out of existence like crazy?