--Vincent Van Gogh
One of the most exhilarating feelings is when you feel the vastness of the eternity of who someone is. As you look at them, the understand that they are a soul, that extends infinitely, actually penetrates your understanding. They are an eternal being; there is no end to them, or the mystery of them. Looking these humans in the eye feels like standing on the edge of a precipice. You feel the absolute Otherness of them pulsing against yourself, pushing against you, tugging at you, shimmering on the edges of the boundaries of your self.
Sometimes this happens with a parent, when you look at them and realize you don't know what they're thinking. Or it will happen with a close friend, your sister, a near-stranger in serendipitous good conversation, or someone you supposedly know very well. No matter when, it takes my breath away as I confront the real miracle of other people. How can it be that there are two persons in this world!? How can it be that two eternal consciousnesses can coexist?
~This reflection brought to you by Martin Buber, since I am also halfway through I and Thou. I don't think anyone really gets more than halfway through I and Thou, even if they finish reading the book. I and Thou was was given to me months ago by a friend whose marks in his books are always buffoonishly cryptic, and mostly just scribbling--the majority of which I'm sure happened while under some sort of influence--but his aimless loops and underlinings and frantic circlings are curiously appropriate for my own relationship with Buber's spiraling text. I am beautifully baffled by it. And my mind turns in spirals, circling around a line of text over and over, trying to bore into the core of meaning that is so lovingly hidden within layers of text.
A human being is not He or She, bounded from every other He and She, a specific point in space and time within the net of the world; nor is he a nature able to be experienced and described, a loose bundle of named qualities. But with no neighbor, and whole in himself, he is Thou and fills the heavens. This does not meant that nothing exist except himself. But all else lives in his light. 
He is Thou, and fills the heavens.
~"The Thou meets me through grace--it is not found by seeking."
How did Adam ever comprehend the existence of Eve? Imagine an all-encompassing, primordial loneliness. There is no other creature like you. It is an entire universe--which you can hold in your mind-- and you. Then, suddenly, from your own side, has sprung forth another human.
Another human, that is, a person like Adam himself, and yet, by that very stamp of being like him, entirely other. And there's the rub. Because, we possess the same properties of human-ness as one another, the property of being an infinite and eternal Thou, and wholly sundered from one another. I can never get inside the boundaries of you: I will always remain within the boundaries of my own infinite. But yet, we can grow to know and understand the other person. The I and the Thou can meet; two infinities can truly touch one another, and love each other.
This, it seems, is the mystery of the Trinity. How can it be that there is a Father and a Son? Both, together, united in eternity, endlessly existing together? Existing is a complex enough idea, and I think I've grasped that. But existing together is an entirely new idea.
Perhaps that is the mystery of the Trinity: that two or three beings can remain absolutely distinct and outside one another, yet participate in the same reality, can be the same reality. The world is a constant dance between the I and the Thou, and this fundamental gaze of lover and beloved is mirrored in all the meetings between I and Thou throughout the world.
The Father and Son's delight in the existence of one another must be the Spirit. It certainly must be a palpable entity outside of themselves. I imagine the joy in being so full of existence, and co-existing with another perfectly existing being must desire the existence of other such beings. And surely this desire has eternally existed within the love of the Lover for the Beloved.
This entire week, I have been thinking of that quote in Chesterton's Orthodoxy
But perhaps God is strong enough to exult in monotony. It is possible that God says every morning, "Do it again" to the sun; and every evening, "Do it again" to the moon. It may not be automatic necessity that makes all daisies alike; it may be that God makes every daisy separately, but has never got tired of making them. It may be that He has the eternal appetite of infancy; for we have sinned and grown old, and our Father is younger than we. 
There is a Sanskrit word adbhuta, which means a perpetual wonderment and amazement toward the world around you. There's a part of an acting exercise that asks you to put yourself entirely in a state of adbhuta, to turn your entire being into wonder and attention at everything around you. You fully immerse yourself in this wonder and awe, and then turn your attention on whatever your mundane surroundings are, only to find that they are not so mundane. The dust specks in the air are flickering lights; the carpet has an entrancing texture beneath your hands; your bones, flesh, and veins are eternally fascinating. It seems that to practice living in that mode of encountering the world is to begin to understand the world for the first time.
Perhaps the stance of Father to the Son is one of perpetual, eternal wonder. And this wonder itself is the Spirit, breathed over the formless void of the universe, breathing us distinct little eternities into existence.
Perhaps God is eternally amazed; and it is we silly sinners who have Seen It All.
For we have lost the youthful glow of paradise and grown decrepit, and our Father in Heaven is younger than we.