Thanks for the A2A Cara. Great question and there a few different ways to answer it.
1. Our awareness of self is only in this instant. The instant that just past is now a previous “self-state.” So any unitive consistency in our personal identity is one that we have constructed in this moment, as part of an ongoing (and constantly revised) narrative. But I would say the “selves” being chained together in this way are…well…infinite.
2. There are about as many different ways to describe separate elements that contribute to an amalgamated self
as there are traditions of psychology, philosophy and spirituality. Experiential, autobiographical, soul, executive, witness, spirit, personas, ego, id, archetypes, and so on. About the only thing that these different perspectives or descriptions agree upon is the necessity of integration, coordination, harmony or the like among these distinct contributive elements in order to be “whole” (or at least psychologically stable). That integrated or individuated self then becomes the ideal, high-functioning self, that is indeed “unified and consistent” in its process of integration/individuation, seeking to self-actualize within its ongoing narrative. In this schema there are then both “multiple self-states” and unity. Of course, there may still be a contrast between the real and ideal levels of function…but that is more of a semantic glitch IMO, as we can easily embrace the dialectic (and even be energized by it).
3. At the same time, you used the capitalized “Self” in your question. If by this you mean some sort of foundational, essential, spiritual Self (as the term is often used), then I would say that this aspect of our being is more unified and consistent. That does not mean it is a calcified nugget without potential for growth, but that it retains certain fundamental characteristics, or “suchness,” that may be fluidly emergent but nevertheless unitive in nature. This ground-of-being Self may also inform our narrative self at times, but (perhaps ironically) that input stream tends to be momentary or fleeting for most people. So again - as a felt experience in the moment, the Self contributes to the “multiple self-states” that unfold over time.
4. There are mental, emotional and spiritual conditions that interrupt the consistency of the narrative self. As one example, we might apprehend the bare reality of our constructed self - or even the essential Self as inhabiting a construct - so that we arrive at an apprehension of No Self, and eventually an integrated condition of No Self. As another example a person might find themselves unable to emerge from a unitive peak experience of consciousness, so that they can no longer differentiate between self and Self. And as Proust famously opined, there is an erasure of self-referential identity during sleep, so that we must “reassemble” ourselves upon waking, which speaks to the tentative nature of all of this.
So to reiterate: an important difference is that our various “selves” are either constructed (generative perceptions) or derived from constructs, where the “Self” is not constructed or derived, but directly apprehended (in the sense of *gnosis*) - after which it may or may not contribute to generative perceptions of self. And yet, in either case, various stages of unitive acquiescence can negate all constructs and perceptions of a differentiated, unique self. So whether the contrast is between self and No Self, or id and ego, or soul and persona, or disparate self-states and unified self-concept, or the unitive Self and operative will from moment-to-moment…well, the definitive answer to your question is likely to always be “both,” and “neither.”
You could say, therefore, that all versions of self are a choice, along with the choice to incorporate unitive consistency (or trajectory). You might even say that our efforts around these choices (to inform, deliberate, idealize, aspire, operationalize, etc.) are a unique feature of our consciousness, and one that is, IMO, pretty darn cool. That is what my book *Memory:Self *seeks to demonstrate in the context of multidimensional self-healing, addressing the contributive elements to self-conception and actualization as “semantic containers,” with many different input streams, which we can actively reshape and reinforce.
BTW you might also enjoy this post: https://www.quora.com/What-is-the-difference-between-the-self-and-the-Self/answer/T-Collins-Logan
You might also be interested in this paper, which elaborates a principle embedded this answer (scroll down link to view paper online): https://www.academia.edu/5724955/Managing_Complexity_with_Constructive_Integralism
My 2 cents.
(From Quora question: https://www.quora.com/Do-we-have-multiple-self-states-rather-than-a-unified-consistent-Self