Look at the tree outside the window.
It is a tree. That is what you call it. That is what everyone calls it. You have been calling things trees since you learned the word, somewhere around age two, and the word has worked well enough that you have not questioned it since.
Now look again.
The tree is also a home for the squirrel that lives in its upper branches.
The tree is also lumber, to the man who passes it on his way to the mill.
The tree is also a property line marker, to the people on either side of the fence.
The tree is also shade, in August.
The tree is also a calendar, dropping its leaves to mark the end of something.
The tree is also a memory, of the afternoon you sat under it with your father, before he could no longer walk to the yard.
Which of these is the tree, really.
The mind wants to pick one.
It wants to say, the tree is really wood. The other things are stories we project onto it. The wood is the substance. Everything else is interpretation.
But the wood is also a story.
Wood is a category that came into use because humans needed a word for the thing they could build with. Before humans, there was no wood. There were cells, fibers, lignin, water. The tree did not know it was wood.
Pull on the thread far enough and the wood unravels too.
There is no level at which the tree is finally and only what it is.
You have a word for this experience, when you have it. You call it being deep.
When you are tired, the tree is just a tree. When you are open, the tree is everything at once.
You assumed the openness was a mood you were having.
It was a description of the tree.
The tree is empty of being just one thing.
This is what the Heart Sutra means by emptiness, and the word has caused more confusion than any other in the non-dual vocabulary. People hear empty and imagine a void, an absence, a lack of substance.
That is not what is meant.
A tree is empty in the sense that it cannot be reduced to a single identity.
It is a home and a shade and a memory and a piece of lumber and a calendar and a tree, all at once, depending on who is looking and from where.
Not partly each of these. Fully each of these. The tree does not have to choose.
Nagarjuna, the Indian philosopher who systematized this in the second century, made a single move that the tradition has been working out ever since.
He said, nothing exists by its own essence.
Not that nothing exists. Things exist. Trees exist. Cups exist. People exist. But nothing exists as a self-contained thing that would be what it is regardless of what surrounds it.
The tree is a tree because of the soil. Take away the soil and the tree is a log. Take away the log's relationship to the fireplace and it is fuel. Take away the fuel's relationship to fire and it is carbon.
At every level, the thing depends on what surrounds it.
The thing does not have a tree-essence sitting inside it like a pit inside a peach.
You do not have a you-essence either.
You are a parent to your child. You are a child to your parent. You are an employee to your boss. You are a stranger to the person at the next table. You are a regular to the barista. You are an immigrant to the people who came before. You are a native to the people who came after.
Which of these is really you.
All of them, fully, depending on who is looking.
None of them, ultimately, because there is no fixed point underneath them all that the labels are trying to describe.
This is not a loss.
The mind hears this and panics, as it always does. If I am not one thing, I am nothing. If I have no essence, I am hollow.
Notice that the panic is doing the same thing the tree does. The panic is a panic and a survival reflex and a habit and a thought and a tightening of the chest. The panic is itself empty of being just one thing.
The panic is real.
It is just not the kind of real you thought it was.
Things are real, and they are empty of fixed identity, and there is no contradiction between these two statements.
You have spent your life trying to find the real you. The essential you. The one underneath the roles.
You assumed that when you found it, all the surface identities would fall away and what remained would be solid.
This is the search that fails.
It fails not because the real you is hidden well. It fails because there is no real you underneath the roles, the same way there is no real tree underneath the home, the shade, the lumber, the memory.
The roles are not covering up the real you.
The roles are the way you appear, and the appearing has no inside.
Hui-neng, the Sixth Patriarch of Chan, said:
From the very beginning, not a thing is.
Not nothing exists. Not a thing exists.
No single, isolatable, self-contained, essence-bearing object can be found at the bottom of anything.
Things exist as appearances, as relationships, as arisings within a vast web of conditions. Not as freestanding units.
This includes you.
You are not a freestanding unit.
You are a way the conditions are showing up at this address, in this body, on this Tuesday morning, while a tree is being looked at out a window.
The conditions will shift. The address will change. The body will be different in ten years. The morning will pass.
What is being called you will keep showing up as long as the conditions cohere.
When they stop, there will not have been a self that was lost.
There will have been a way of appearing that is now no longer appearing, the same way a particular configuration of light on water is now no longer that configuration.
This is not nihilism.
The tree is still there.
You are still there.
The morning is still there.
What has changed is that none of these has to be defended against the discovery that it is not made of essence.
You can let the tree be a tree and a home and a memory.
You can let yourself be a parent and a child and a stranger and a regular.
You do not have to find the real one underneath them all.
There is no underneath.
There is only the appearing, fully and continuously, in every direction, for as long as the conditions hold.
The tree outside the window is doing this right now.
It is not worried about being only one thing.
You can stop worrying too.
Sources: The Heart Sutra, ~350 CE. Nagarjuna, Mulamadhyamakakarika (Fundamental Verses on the Middle Way), 2nd century. Hui-neng, Platform Sutra, China, 7th century.