@Fil Albuquerque,
I'll tell you what the "I" really is, Fil.
The "I" is close, the real answer is "Information".
When we say "Us", again we're close, the real answer is "Universe".
People are "pieces" to a "puzzle" (Universe).
If you observe how angry people with no control tend to control other people to compensate for their lack of control, you can see the Universe's evolution between two entire different stages of the Universe. One stage is the "virus" to our humanity called "anger, fear and the obscure". Those who imprison others for this sick sense of comfort are not doing this on a human level - this is a subatomic event that happens in the Universe. The lowest stages of universal development (i.e red frequency) don't let its energy free - it CONSUMES & IMPRISONS life. Then throughout time, it grows out of its red frequency, reaching higher frequencies, which create qualities of "humanity", (i.e green & blue frequencies). That's when consumption and imprisonment is no longer a "thing" - it's the "past". People who cage anything are subconsciously representing their own "caged-mind". It sounds absurd, but heed my word, everything we do on this macro level has ties to the subatomic and super-atomic world - as above; so below.
That said, the "I" is simply based entirely on what "we learned". Not "what we want to be". Not "what others want us to be". We are information - information comes from somewhere; the Universe. There is no way to define ourselves without using everything outside of ourselves as relation points to understand ourselves through the rest of the world. We need objects and concepts to cross-relate ourselves with, else we have no cross-implication. We cannot understand the individuality of an object/concept unless we have objects around it to say "it's not the objects around it, so let's call it X".
The "I" is interesting because it cannot answer the question "Who am I". I once had a dream of the shadow archetype answering this question in a way that may surprise you: "If you say you know me, then you don't know me. If you think you know me, then you probably know me." I was told by a shadowy figure in my dreams words wiser than any man's on this planet. The subconscious is a connection to this Universe's subconscious. Hence why we do not go to ideas - ideas come to us. Geniuses repeatedly demonstrated daydreaming inventions and coming up with ideas in the strangest of places - all those times, we say it was their idea - but was it really? Or was it the Universe communicating through great minds?
The "I" is based on consciousness. Consciousness is based on water and electricity formulating pictures via the brain, because water can "reflect" - our eyes, brain and body have a close-knit relationship with "water". Water is so important to consider as consciousness, that when you cry, different tears represent different reasons of crying. I'm not even joking - research that when you can, so you can see that our tears are designed much like everything else. I can prove that water can produce life, like consciousness because amoebas produce serotonin chemicals - those chemicals create "humanity" and make "humanity" possible. Not only that, serotonin becomes melotonin, which is what creates those profound dreams we experience at night - another piece of evidence that "water" is manning our perception, our consciousness and our experience of "I" or "Information". The brain bathes in chemicals when we sleep which to no surprise, made up of 99% "water". The next time you interact with water - look deeply into it, because you're staring at the fundamental creators of life. Respect it - as I respect it. Acknowledge it - as I acknowledge it. Live for water, not let water live for you - as I live for water, not let water live for me.