You say that there's no mystery. I say that you're wrong. Because it's all a mystery, that exists in the space between our ears. So, when you get right down to it, we are, all in fact mystics.
OK, let's say it is a mystery. This may well be one area in which I (gasp, choke) almost agree with a position of Iacchus, though I might suggest the mystery is external to the space between my ears (I cannot speak for what rattles around in the great echoing expanse between the ears of Iacchus). But a mystery is, by definition, something which cannot be explained. You continually attempt to explain it, and I'm sorry to say that from where I stand, outside that space between your ears, the explanation continually falters.
I have a question now about the idea that the universe exists within space, as a circle within a circle. I realize that this is meant as a symbolic representation, but still, for such an illustration to make sense it must elucidate in some way the properties of the thing illustrated without logically violating the very thing you're speaking of. So, a circle within a circle. This requires that one circle differ in some substantive way from the other. If they did not, they would be identical, and then we could not use the word "within." Our illustration would be of one circle. This difference must be some property of the outer circle which is not contingent on the inner one. There must be some aspect of the outer circle which is not at the same time an aspect of the inner one, if only the quality of dimension or cardinality. For the analogy to make sense, we must be able to describe or define the outer circle without referring to the inner one. Now it is customary to consider the universe to consist of everything that exists, with the exception of God, if you are inclined to believe in God. If you believe in God, it is necessary that God exist either outside or in addition to the created universe, or he would be contingent on his own creation, a big no-no. The logical dilemmas inherent in any consideration of God are irrelevant here. We will, for the moment presume that if there is a God, God transcends logical limitations and defies understanding. However, since it would be a very slippery idea to suggest that space is within God, nor is it God himself, nor, apparently is it the universe or something within the universe, then what is it? In what relation do God, the universe and space stand? If you say the universe exists within space, there must be some space somewhere that is not part either of the universe or of God. And yet, is not the universe defined as everything but God? If it is not thus defined, must we not come up with a new word to describe the thing which is the universe plus everything else that is not God? If there is no space that is outside the universe, then space and the universe occupy the same domain. One cannot enclose the other.
I think the reason for this goes beyond poor mapping to a fundamental flaw in the way things are being considered. It would also be considered minimally necessary that the circles be illustrating things that have some ontological equivalence, or inhabit the same plane of existence, as it were. By this, I mean that you cannot, for example, draw a map that shows things that are not mappable. An abstract concept, such as the meaning of the word "noisy," is not a legitimate component of the New York subway map. We've already beaten sets to death, but a diagram illustrating the set of all oranges cannot contain as an element the color orange, not only because the color orange is not an orange, but because the color orange is not an object, and therefore cannot belong to a set of objects.
I contend that your analogy of a circle within a circle is fundamentally flawed, because to produce such an analogy the two circles must be describing things which have some ontological equivalence. You cannot meaningfully say, for example, that the orange on my plate is contained by the color orange, any more than you can say that the object contains its property in the same sense that you say a box of spaghetti contains spaghetti. The box of spaghetti contains spaghetti and the spaghetti is white, but the box of spaghetti does not contain the color white. Space can exist within another space, a group of things can exist within a group of other things, a galaxy can exist within the universe, but to use the circle analogy, one must be saying that space and the universe are each entities in their own right, and that the container is not entirely contingent on its contents.
So are you actually asserting that space is an entity in the same sense that the universe is an entity? Are you saying that there is space that is not in the universe? If you are not intending to say both things, the illustration of a circle within a circle is not an adequate one.