What you do is what the whole universe is doing at the place you call "here and now," and you are something the whole universe is doing in the same way that a wave is something that the whole ocean is doing... The real you is not a puppet which life pushes around. The real deep-down you is the whole universe.
Naturally, for a person who finds his identity in something other than his full organism is less than half a man. He is cut off from complete participation in nature. Instead of being a body, he 'has' a body. Instead of living and loving he 'has' instincts for survival and copulation.
Time is a social institution and not a physical reality. There is no such thing as time in the natural world - the world of stars and waters, clouds, mountains and living organisms. There is such a thing as rhythm - rhythm of tides, rhythm of biological processes... There is rhythm and there is motion. Time is a way of measuring motion.
Other people teach us who we are. Their attitudes to us are the mirror in which we learn to see ourselves, but the mirror is distorted. We are, perhaps, rather dimly aware of the immense power of our social enviornment.
You will never get to the irreducible definition of anything because you will never be able to explain why you want to explain, and so on. The system will gobble itself up.