There are a lot of barriers for us to interact with the rest of the world. The most obvious one could be your skin or your brain. Nobody can touch your internal organs, nobody can read your thoughts.
However, today, at the age when biology is programmable and neurons will soon be hackable, how will we protect whatever we define as “self” from others.
And if an invasion happens before we even notice it. How do we then know which part is “us” and which part is “invasive”?
And how do thoughts and cells inside us today know where they belong and recognize each other? It is not surprising, that despite our understanding of biology and neuroscience — those questions still remain open.
Moreover, in physics, there exist much more profound debate regarding the nature of reality. Given that within the paradigm of Quantum Mechanics, there is always distinction between the observer and observable, and decision which reality do we live in depends on an event of observation of a few atoms of this universe — some suggest that there is something more profound to matter and space and time. Something that makes up those experiences and cognizances. And this still remains an open question, as you may guess…