In Zen, “Who am I” is a big question, which should be always asked. But in daily life, it can not be a question, because everybody “knows”. The key point is how we understand “I”.
Your name is “I”? If you change your name, the “I” will be changed. If you have several names, which one is real “I”? So the name is just a mark, which represents a specific person or image in a specific condition. The name itself has no definite meaning. But we always regard the name associated with a person or an image as a specific “I”.
Your body is “I”? When we say ”I feel headache”, it seems that the headache is “I”. When the headache disappears, the “I” seems recovered. The body consists of four elements: earth, water, fire(heat) and wind(air), and they are changing in moment. The existing and sensation of the body are just the reflection of changing elements. We can only say: the body is temporarily related with a specific name, but there’s no fix “I”.
Your mind is “I”? When we say “I feel lonely”, it seems there’s a lonely “I”. When the feeling of loneliness fades away, the normal “I” comes back. The mind consists of four aggregates: feeling, perception, formation and consciousness. And their arising depends on all kinds of conditions at the moment, but none of them is “I”. Just like when looking at the light of a bulb, we ignore the consistent flowing currents.
We don’t deny a “temporary I” – a dependent arising of name, body and mind. But neither of them has a “fixed I” – “inherent self”. Normally, we unconsciously regard this “temporary I” as “fixed I”. Buddha always use “the flower blooming in the sky” or “the mirage in the air”, to describe this kind of cognitive illusion.
“Who am I” is not a tricky password, but a real question!