One more note (for now) on this topic, the subject of my posts yesterday and the day before.
There's now experimental evidence that we actually make certain decisions slightly before we become aware of having done so -- the circuits for taking action begin to fire before we report deciding. One question such evidence raises is about the actual function of the conscious mind; is it just the brake on ill-considered choices by other parts of our brains, or is it instead the rationalizer of them ( to persuade ourselves or others of the rightness of what we've already done), or does it come into play, perhaps, for some more complex set of decisions whose nature isn't captured by the experimental reports? But for now I'm not concerned with the question of what the point of consciousness is.
Rather, what's interesting about this evidence, in the context of the question of who exactly we are, is that it indicates that some part of us besides our conscious minds makes some of our decisions. Presumably that part of us also thinks about those decisions, in some way or other evaluating the pluses and minuses of possible courses of action. Perhaps this part of us thinks in very primitive ways, but it thinks. (Reflexes may not be examples of "thought," but my impression is that the decisions I'm focusing on are not so instantaneous as to be reflexive.) And "we" don't have direct access to those thoughts, until they emerge in the form of an already-made decision.
Perhaps these masked thoughts are available to us through dreams or psychoanalysis or both. But at the least it seems to be the case that anyone who has not achieved such access is operating partly in the dark about his or her own self. And it may be that even when we achieve greater (perhaps never complete?) access to our own thoughts and feelings, what we find is not that we are in fact a single coherent person after all -- just now visible at last -- but something more like a core personality and a periphery, made up of routines (emotions, thoughts, reaction paths) that actually aren't integrally connected to the rest of ourselves.
It's often said that we aspire to wholeness, and that age helps us to achieve this. But the corollary of these propositions is that for many of us, or for all of us in some respects, we are not in fact whole. "We" -- that is, single fully organized "I's" -- don't quite exist.