1.a person or thing referred to with respect to complete individuality: one's
2.a person's nature, character, etc.: his better self.
a.the ego; that which knows, remembers, desires, suffers, etc., as
contrasted with that known, remembered, etc.
b.the uniting principle, as a soul, underlying all subjective experience.
We like to think we own ourselves, the very definition adds "one's own self." But do we? Many believe the self stems from a soul, a divine given source of identity and individuality. In most scientific communities, the self is believed to stem from either genetics, environment, or the complex inter-workings of the two. But none of these views seem to give evidence that the way we are is something we choose. I myself can't get my mind around the idea of the "self" because if it isn't under our control at all, why should we bother with the idea of the self at all? Is everything we experience in life simply a combination of genetics, environment, and chance? But on the other hand, I can't think of a way to convince myself that we choose who we are, because even when we choose to act a certain way, those decisions still depend on the previously mentioned genetic, environmental, or divine factors, depending on your beliefs.
So it seems likely that our choices aren't as much a choice as we might like to think. Personally, I have no idea what to think of the "self." But I think it's important to question our concept of the conscious self before we even attempt to tackle the idea of an additional, more mysterious counterpart. The unconscious is viewed as a sort of mysterious thing that reveals itself in cryptic dreams, or Freudian slips, which if you aren't familiar are those instances when we call a friend or teacher "mom," or any other slip of the tongue, that according to Freud revealed unconscious feelings or desired. But neurologically speaking, the unconscious is in essence the thoughts we can't put words to, or even more simply, the processes of the reptilian brain- the emotions, instincts, etc. that we share with most other mammals.
What makes this part of our brain so alluring to us is that it's unknown. We like to think that not only do we control our actions, but that we understand ourselves, at least for the most part. But in truth, do we? An article in the New York Times asserts that
We have company, an invisible partner who has strong reactions about the world that don’t always agree with our own, but whose instincts, these studies clearly show, are at least as likely to be helpful, and attentive to others, as they are to be disruptive.