Do you agree that you exist?
It depends on what you mean by "you".
If you mean the body, sure.
If you mean the 'thing in my head that I identify with as me', then not sure sure.
"I think therefore I am," doesn't make sense when compared to the question, "If you don't think, are you there."
When I don't think, and it's all shut off, there is no "me" anywhere. Even when this happens while the physical eyes are open, the body is there. The identifying apparatus simply is shut off. The identifying apparatus is really just a labeling of a series of chemical processes in the brain, so to collectively call it an identifier indicates that it is a thing that identifies, or gives the sense of identity. However, it's not a separate thing that can be called as such, as aforesaid. It's more like an apparatus, a series of mechanical and chemical workings that result in the appearance of one who identifies.
Do I think that exists? I think that exists insomuch as it thinks it exists. But if it isn't thinking, then it isn't existing, and therefore it's existence is not independent. It's existence is also dependent upon a physical body, for without the mechanical and chemical working it simply wouldn't be there. So it's existence, in essence, is a figment of the imagination.
I do understand where you're coming from, your arguement is reasonable, so lets say 'you' exist and thats the only thing you can be sure of!
From this it seems that you are equating the mental image, or cumulative identity with existence, and not the physical body that creates the cumulative identity.
Everything else is external, mixed with emotion coloured by imagination.
For practical, conventional purposes, I do see and interact with things appearing as 'external'. However, the words and images the body is interacting with are built from the internal apparatus.
What really separates me from the tree outside? It's the thought that there is an "I" which is a separate entity than the "tree". This line of thinking returns the idea that the body is "a part of" the universe, and creates a sense of separation from the whole universe. This is isolation, which is in my opinion the very opposite of compassion.
Change the word 'I' and use the word 'awareness' or we are always 'aware' but distracted so we are not conscious of it.
I don't so easily equate the word "I" with "awareness".
I don't want to say too much and clutter the mind. Lets say you stay with the 'seedbed' of being and leave it at that.
Too late. If you have the answers, give it straight.