We actively construe reality. If we imagine the mind as a hierarchy with raw sense data at the bottom and abstract ideas at the top, we construe reality by bringing hypotheses from the top down to the bottom to test against the sense data and bringing the data up from the bottom toward the top to confirm or disconfirm the hypotheses. We understand the world from top down in order to understand it from bottom up. Our minds are simply not built to do so. This model from cognitive science fits precisely the psychoanalytic account of personal identity as a theme and variations.
Identity is at the top.
That is, the hypotheses I bring to bear, the hypotheses I choose from all that my culture offers me, the way I sense the outcomes of those hypotheses, what outcomes will satisfy me, how I feel at confirmation and disconfirmation, all these express my personal style or identity. All are, in varying degrees, personal. That is, my personal identity puts hypotheses out into the world. Some of these hypotheses are physiological and are much the same for all human beings. I see colors the same as just about anyone on the globe.