As entities of pure energy the sub-molecular bonds of ghosts are different than those of seemingly solid matter. It is due to this fact that we find an area of understanding as to how the ghosts can move through seemingly solid objects. Although the ghost can not, by any means of will power of other psychological facility initiate this process, it will naturally occur as the ghost passes through an object. As the ghost passes through the object their sub-molecular bonds may restructure, reorganize, or slightly bend themselves to allow for a certain amount of natural adjustment or modification so that the ghost may pass through the solid object. This process would not cause the ghost to have any sort of sensation as it takes place and thusly the ghost would not notice the process as it would occur.