What is Oneness?
The shortest answer I can offer is, "This is."
Though I assume, dear reader, that is too broad an answer, even though I'm actually being very specific. I won't ask you to open your mind in order to better understand this post because I'm well aware that it cannot be closed; though one can resist and cause oneself much pain trying to stay attached to a thing that one cannot be attached to. But I digress; lets start off with a pretty picture shall we?
What I hold in my hands are two entirely different, yet practically the same, images. In my left hand, I hold an energy mapping of the entire universe as we know it, in my right, a mapping of the human brain. This image, in itself, leads me to believe that our consciousness is relative to that of the universe. Now please allow me to bring up some other, easy to follow points to both the spiritualist and the scientist in the speculation that All is One.
Firstly, one for both sides of the coin. The air we breathe. The air we breathe, we call "Prana" or "Life Force" in Yoga (which is a practice of unionizing mind, body and breath, and has to do more with way of life than a religion). We can sustain life in our bodies without food for some time, without water for a few days, but we cannot live without the breath for more than a few minutes. All of us, people, animals and plants are breathing in and out this life force and recycling it for one another. The air you are breathing in and out right now has come and gone through the systems of countless others and will go on to countless more. We all share this abundance now and forever.
This life force stems beyond just the breath to the water and the food we consume. All of it comes first from the Earth's matter which came from the galaxy's matter, which came from the universe's matter, which came/comes from... One's perception. Everything is shared and recycled and those who do not share nor recycle tend to move towards an over stressed or ended life (in the separation that I am not He/She/Them/They). To be [One] or not to be [Zero], that is the question.
On the science side, quantum physics now theorizes that everything is energy simply slowed down to the point of having a physical reality. If we could (and we can) look beyond the spectrum that the typical human eye picks up, we could see the "energy soup" we all are constantly residing in and interacting with. In the fullness of the unseen spectrum, we are countless energy particles and waves that are not separate from one another but are clearly inter-connected.
Alright, how about One more example? With 100% of everything (1.00 = 100%) in the universe, each One of us has One point of constantly changing view, and most, if not all of us, believe ourselves to be the righteous One. EveryOne has a perfectly logical reasoning as to why One believes as One does; every One. When One experiences reality, One decides (with or without training; which is why I am dedicating my life to teaching things like yoga, qigong, and more) to pick out certain details that define themselves and their universe around (and by universe I mean all that one perceives in the single One moment of Now). Mostly we look at what seems like outside ourselves and make judgments or hopefully just observations, on what is going on out there. But remember, there are 7 billion Ones! And that's just the people! We can only ever focus on a tiny percentage of what is actually going in the world. I don't care how many subscriptions you read or TV you watch, One knows very little about the bigger, constantly changing, picture.
Life can be complicated, but it can also be so incredibly simple. The war that is being fought on the front (outside the body) is being perceived by the universe within. If One is ready to end the war and have universal peace, then all One must do is begin observing within; the thoughts and feelings that may or may not turn into actions and/or a belief system. We are All One and we create ourselves either by choice and taking responsibilities for our own personal universes, or not by choice, by chance. I highly encourage you to go find yourself a teacher (or rather a guide, Oneself is always the teacher) of the internal arts (yoga, meditation, qigong, etc.) and be sure that that person gives you more than just a physical workout.
Truly, all must be unionized into One functioning being; a mind, a body and a breath that connects. The God/energy that creates me recognizes the God/energy that creates you. How about we work together (as we already are and will forever be) and create something that is absolutely Phenomenal and Out of this World!
It is only now, once, forever.