With this understanding, you can grasp that all the ascents and descents mentioned with regard to the higher worlds do not refer to an imaginary place, God forbid, but rather to the concept of the four levels of will to receive. Anything that is distant from the fourth level is described as being in a higher place, while anything that is closer to the fourth level is described as being in a lower place.
However, one must understand that since the central element of a created being, and of all of creation in general, is solely the will to receive, anything beyond this is not actually in the category of a creation but rather emanates from the Creator’s essence yesh miyesh; that is, it constitutes the light of vitality found within the creation. If that is the case, why do we describe this desire to receive with negative appellations such as opacity (ovyut) and murkiness, and why is it that we are commanded to purify it by means of Torah study and commandments to the extent that without this purification we would not achieve the lofty goal of the Creator’s intent for the Creation?