'But how does it work?' Explaining magic to humans

Sunday Prompt Gold #5: A technology lost, forgotten or shrouded in mystery a recipe is ok. 15 mins
No one alive today can explain why Nioshi exists as it does. A land circumscribed by ocean that drops off the side of a plane of existence - talk to anyone who doesn't live in a world founded on magic and a genuine power of belief, and they cannot understand it. Even if they see the edge of the world with their own eyes, they must ask, "But how does it exist? Where does the water go? Why does it not run out?" A Nioshan can only explain that the ocean exits, and continues to exist, because the water is there. All Nioshans believe in the vastness of the ocean. They see it with their own eyes. So of course it vast, and of course it is there.
Humans are particularly skeptical of our world's construct, despite possessing some of the magical power of belief-actualization that seeped from Nioshi into their world millenia of their Earth years ago. Most of their own deities, ancient and present, are made of the matter that makes up all of Nioshi. When belief fades, the existence of a thing fades, releasing the matter back into its primitive energy state. In that form, it flows around all of us, listening for the next name it is called by, hearing how it should manifest itself to best be believed by the namers.
This is not to say we don't believe that we are real. We are as real as anything else that believes it is real.
One may wonder what stops a consciousness with awareness of its make-up from taking all power for itself, from consuming a universe. Our explanation is that consciousness comes with a cost. For Nioshans, our power is limited by the scope of our physical definition. For example, if a lifeform has arms, its capacity to reach out is limited to its extremities. For humans, their cost of self-awareness is a species-felt affectation of loneliness. Philosophers for generations have explored the concept of human loneliness, of the great expanses that exist between and among individuals, collectively between groups of human, the great babbling chasm between humans and animal life on Earth. For all their musings, poetic though they are, few have come to understand that the distance is causality: cells come together in a dense locus, driven together to work a complex structure to hold self-aware magic, and naturally leave around that locus an emptiness. Great cities bustle with energy and manpower, while surrounded by rolling countryside speckled with quiet, lonesome fields, lowly populated by the farmers whose houses dot the landscape like scattered seeds. One cannot exist the way that is does without the existence of the other. A uniform field can in theory exist at a moment in time; but the times that any world, especially the Earth world, achieved such stasis, were naturally short-lived. Life, after all, relies on the chaos of change like a human relies on air to breathe.
Air is another Earth concept that no one can explain. A magic bubble exists to surround the planet, within which, every living (land-dwelling) thing can breath. Like a membrane, it protects the world inside it, and acts a barrier designating where a human is and is not allowed to exist. For a short time, they left that barrier in small numbers, exploring -- for no human is bound completely by his beliefs -- and go to great lengths to bring their air with them. They believe they run out of air and will go so far as to die to prove their point. Yet asking them to consider the possibility that air itself is magic, existing on a bedrock of belief in human thought, is to much. They have a great capacity to spin contradictions to prove their point. Case in point, babies, in utero, do not breathe air; humans agree this is true; they also agree that the unborn child "lives" and "breathes" with its lungs, specialized in one moment to move oxygenated fluid through its lungs. In another moment, the same lungs touch air, and are no longer capable of breathing liquid. How peculiar! It's no wonder that babies cry when they are born: so many humans believe their very lungs into instant evolutionary transformation at the moment of their exit from their mother's body, the changes must be overwhelming.
Take another example that some few humans will die and return from death, even twenty minutes journey out and back to the body. Even so, the average human will tell you, "Ah, no, death is the end. You cannot come back from it. No, you see, the human body can only survive but a few minutes."
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