There have been some great questions lately around this idea of existence. We might as well talk about the Vedanta concepts of Mithya and Satyam. These concepts have the capacity to cut away the delusion of separate "thing"- ness.
We have a paper cup. We all know what that is. It is identifiable. We may use one every day for our coffee or tea, for our water at the cooler. But what IS that "thing"?
If we look at the concept "paper cup" - we might ask a question. Cup is the noun - the "thing". Paper is the adjective - it describes the "thing". So from our common language, we have the "cup" as the thing itself and paper describes the cup. But "cup" isn't really a "thing" - it's a function - a purpose - a utility - a way to hold liquid. Paper is actually what it IS. So at this point, the "thing" is Paper in a particular shape "cup", yes? We might now call it, instead of "paper cup," "cup-py paper." Paper, in the shape, form, and function we call "cup".
So the "thing" is paper. But is paper really what it is? Well no, actually. "Paper" is a word we use to talk about the stuff created when we take organic material - trees - grasses - and manipulate them so that they become "paper". So "paper" really is that organic material we know in trees, and grass, and paper. But what is that organic material?
A tree is basically a big plant - a plant that has a trunk and some branches - it might blossom flowers, oranges, apples, leaves, acorns, etc. It is organic - that means basically that it is living material. To say it is living material means - it is cellular - it is composed of various cells that give it the ability to interact with it's environment - to grow, etc. But what is a "cell"?
A cell is the basic component of any organism. It is a mass of molecules - the chemistry of which - the electrical charge of which - enables this cell to grow - to reproduce - to interact with the surrounding cells. These molecules are masses of two or more atoms - bound together by chemical and reactions. And atoms are even more refined "things" - they are protons and neutrons, surrounded by an electrical charge - electrons - mostly empty space - yet the unique makeup of each "atom" - the unique formation of the protons, neutrons and number of electrons, make one atom distinct from another. The atomic "weight" or makeup is the difference between a puff of helium and a gram of iron.
So let's step back and restate this. There is some "substance" of which the atom is made - the proton of the helium and the proton of the iron are not really different - it is instead the unique configuration of these pieces, and the number of electrons (or electrical charge) that creates the difference "helium" or "iron". Yes? If I take the proton out of the helium atom and the proton out of the iron atom, what is the difference? If I compare the electron of the helium atom to the electron of the iron atom, what is the difference? It's really the number of electrons, the behavior and how all those pieces interact, which makes the eventual form "helium" and "iron". At that level of experience, they are vastly different - yet at the level of the atom they are really quite the same. In fact, at this point, we might wonder what is the "substance" of the atomic pieces?
We are really, in this exercise, trying to find where is the distinct existences in these "things" - at what point did they come into existence? We can now rightly say - atom IS helium - atom IS iron - atom IS tree - atom IS paper - atom IS cup. At the same time we see "cup" we are seeing "atom". We don't have "atom" then that disappears once "cup" arrives. The "cup" is simultaneously atom and paper.
So along the way - we had some carbon elements - some hydrogen - some nitrogen - all these were there - and STILL ARE - when it was tree and now while it is "paper cup". The same "stuff" is there - only that "stuff" is shaped differently - formed differently. It's still the same "thing", in essence.
So what is that "substance" - from the atom we must go to the sub-atomic level - the level of quantum physics. Physics basically describes the way things behave. We can't really "see" what the atom is, at that level, yet. We can only derive theories around the behavior, then give those hypothetical sub-components a name - quarks - strings - etc. We suppose that what the atom IS, is a series of quarks and strings - what those quarks and strings are we aren't sure, but at this point we must stop and ask - each time we dive into WHAT that "thing" is - we find a way to give it's components some names. Yet the quantum string and the paper cup are one and the same - it isn't a quark now and then later becomes a cup. It is simultaneously quark and cup - we see the cup - a quantum microscope might see the quark, when it looks at the cup. So what that thing "IS" is NOT DEPENDENT on it's form or shape or function - it is NOT DEPENDENT on the present experience OF THAT THING. In other words, WHAT that "thing" is, to someone looking with eyes, is "cup". WHAT that "thing" is, to someone with a quantum microscope, is a "quark" - or a mass of quarks and strings, which are ALSO atoms, neutrons and electrons, which are ALSO molecules, ALSO cells, ALSO trees, ALSO paper.
When you're looking at the world, you can only see what your senses have the capacity to see. Your eyes are not quantum lenses - therefore you don't see the quarks - yet right in front of you is a trillion-trillion-trillion quarks. You just see what those quarks are, on the level of eyes, on the level of consciousness. So in a way, our senses fool us - we take the world at surface - we take that pencil as something separate from the chair - we take the cheeseburger as separate from your watch. What we BELIEVE - our IDEA of reality - is that it is made up of an infinite number of "things" - watches and cheeseburgers and chairs and pencils and cups and trees. We forget that those things are ONLY watches and cheeseburgers and chairs and pencils and cups and trees FROM the perspective of our experience - our sensory capacity. They are also, simultaneously, cells - molecules - atoms - quarks - strings...
But what ARE those things, in essence? We have broken down every "thing" in the universe, basically, to the quantum level - to quarks and strings - but even a quark and string must BE SOMETHING - if our analysis holds true - a quark or string must really just be another level of experience - another form-ation of "something" - something which we have yet to discover through science yet we really can't deny at this point that "something" smaller must be there - the quantum material must have those components - WHAT the quark and string really ARE, in essence.
Let's say in 10 years we discover that the quark is made up of jibjabs and knickerdoodles. So is that it? Are we done? Jibjabs and knickerdoodles must be the source of existence, right? No - because once again we must find out what a "jibjab" and a knickerdoodle" really IS, in essence. Because now we KNOW that a "thing" is just an appearance or expression based on the level of the ability to experience. A jibjab is also a cup, yes?
We can continue like this forever. At some point we run out of experience-able "things" - we basically have this empty space which is behaving in ways that we can later identify as some "thing" - electron moves slow and we have iron - electron moves fast and we have helium. But electron is basically space with an electric charge. So that eventual "thing"-ness is REALLY just the way "space" is behaving.
Can we say that again? Isn't that "thing" - the cup or tree or pencil or ham sandwich - isn't that "thing", in essence, just there due to the way "space" is behaving?
Once again, let's step back. Look around you - look at all the "things" in your experience. There is a cup - a pencil - a computer screen - a chair - a wall. That wall is space - behaving in a way that appears solid - that appears a certain color - shape - size. Yet "wall" is molecules - atoms - quarks - "jibjabs" - whatever else we might conceive to describe all the subsequent ways that space is behaving, yet we must consider that we have falsely applied separate "thing"-ness to that wall, as if that wall was born - AS IF that wall came about independently. AS IF that wall has some separate EXISTENCE somewhere. From this analysis, can you identify WHERE that separate existence IS? At what level would it be?
Really the "existence" of wall is what that wall really "IS" - when we boil it down this way, we must say that "wall" really is space-behaving-in-a-particular-way-as-to-appear-as-wall-to-our-present-ability-to-experience-it. Well that would be very difficult to use in a sentence, yet isn't that really what that "thing" is? Isn't that what the pencil is? The paper? The tree? The ham sandwich?
This is a long way to go to talk about Mithya. So Mithya says that any "thing" we can know does not exist on it's own but has "dependent existence." "Wall" doesn't exist by itself - molecule doesn't exist by itself - it IS atom/proton/neutron/electron. Atom doesn't exist by itself - it IS quark/string - and so on. Quarks and strings are really the way "space" is behaving - the way space and the "energy" of that "space" is moving or behaving. There isn't one "thing" here acting upon another "thing" - each having it's own existence. It is one "thing" - in expression - those expressions are quarks - those quarks are atoms - those atoms are molecules - those molecules are cells - those cells are cups and pencils and everything else.
Cup is Mithya. Pencil is Mithya. That which has no existence of its own -that which has "dependent" existence. Satyam is what-IS - well we never really could define WHAT that root essence IS - yet we might say that any identifiable "thing" in our analysis can't be it. We can use the concept of space in expression, maybe - limitless space or no-thing-ness - whatever THAT IS which exists.
Once again - we must step back. Existence is both the limitless and the pencil -because they are really the same "thing". Existence is both the limitless AND the ham sandwich - why? Because they both are present right now - only available to us through our particular means of knowledge - eyes, ears, taste - or through an atomic or quantum microscope. Vedanta calls spirituality that other means of knowledge - really to know WHAT those "things" ARE, in essence, because we don't have a scientific means of knowledge. We can only measure what appears to our ability to see it. Yet all the while, we are looking right in the face of that essence - we are seeing that limitless-ness in expression - right now. Pick up the pencil - you are looking at existence, in expression.
We know Satyam - what-IS - in any "thing" - why? Because any "thing" IS THAT, whatever THAT IS. To say pencil is a separate thing, to believe that pencil is a new existence, a separate existence, something that is subject to birth and death, is to overlook this sort of analysis, to be caught by our particular means of knowledge, to live, really, in an illusion where "things" have existence of their own, where all "things" are separate. It is to be caught by Mithya.
Realization is simply to see through Mithya - to see the simple truth that "things" have no real existence, no birth or death, of their own. Realization is to see that our experience of a world of things is really an experience of one "thing" - one "Essence" - one "existence". It is an experience of one essence, expressing as every - "thing".
Where does that leave you? You are aware of these things? So WHAT is aware? WHO is aware? If all things are that one essence - then you must BE THAT - you must be that one essence, expressing in a very complex way, so as to be aware. That means that essence is, through this mechanism, aware of itself. We might say that the universe has become self-aware - maybe we might say the universe has evolved so that it can look upon itself - it can know itself. You are THAT.