The spiritual world consists of the same parts and connections between them as the material world. However, we can only feel the spiritual world to the degree our sensations enter it.
Forces descend from Above into our world, and they have inanimate, vegetative, animate and human qualities. This is what we observe: the expression of the Upper Forces in our world as objects and actions.
Our encounter with the details of perception gives rise to the forms. For example, say I see an object before me now. It appears to me in a specific form, but if I had different qualities, then I would see a different form. Baal HaSulam gives the example of a table: I see it one way, but an angel sees it through its qualities.
Reality or perception is produced when my qualities unify with the Light’s, due to our having common or similar qualities. Beyond my perception, there is only Infinity, out of which I perceive just the part that I have shared qualities with. So how can I attune myself to having shared qualities with the Upper World? I can do it because inside me, I have the same coordinate system (world–year–soul and a ready-made reality) as it has inside. And when I ask for it, the Upper Light makes my system similar to the Upper Level. This is called the correction of the soul. It’s when I make my inner system similar to Infinity, in a specific measure. I thereby determine my spiritual level and the degree to which I perceive Infinity.