One of my favorite experiences during my time at Arizona State University will always be that afternoon when I attended a colloquium where Joshua Knobe presented on the true self as moralist. (See these papers: "Value Judgments and the True Self" and "Person as Scientist, Person as Moralist".) This view is contrasted to two different conceptions of true self, one of them intellectual and the other emotional.
Imagine a person is in a state of conflict as to what she ought to do in some circumstance. She feels a strong desire to cheat on her husband with this other man, she really feels as if she loves him, but she believes strongly that adultery is wrong and that she ought not do it. Which course of action, if realized, would be an expression of her true self? The intellectual conception entails that her true self would obey the moral command not to commit adultery, whereas the emotional conception entails that her true self would commit adultery with the man she loves.
Knobe found that actually neither concept of self is adequate, and that in various different circumstances, persons may intuitively judge that sometimes the emotional self is true and other times the intellectual self is true. Knobe found that most of the time, people tend to judge the true self in accordance with their moral values -- that is, if a person believed adultery was wrong, then she tended to judge that the true self would be that whose manifestation would be to abstain from adultery. Alternatively, suppose the woman is propositioned by a man who is not her own husband, and she feels deeply that something is off about the whole matter, but she believes that there are no binding moral truths and thus that it would not be strictly speaking wrong to engage in adultery here. In these cases, people tend to identify the true self with that emotional sense of wrong, rather than with intellect. Knobe infers from this that actually moral commitments are informing our judgments.
(Now it is true that persons have different moral notions, and so they will not agree on all the details of a true self. A person who thought uninhibited sexual expression was good, for instance, would judge that the self which manifests in adultery in the above considered cases would be the true self, in contradistinction to the prudes and puritans out there who lack this progressive vision. But that doesn't matter, ultimately, since the point is that true selfhood -- metaphysics -- is essentially connected with moral vision, with ethics, regardless of the finer details of the latter.)
If this is our conception of the true self -- that is, our true self is the self that acts in accordance with our moral commitments and principles -- then how ought we to understand freedom?
A lot of persons understand freedom in a kind of existentialist way, presupposing a notion that "existence precedes essence," that is, that a person is free more or less to define herself as she wishes with her actions. True freedom on this view means being able to sculpt yourself into whatever statue you like, having multiple variants at your disposal. This presupposes a conception of self as undefined and free; it presupposes that you define yourself, that your true self is not predefined or directed for you.
Knobe's studies suggest a different picture. If our true self is essentially moralist, then we would infer that true freedom is being able to embody that self. True freedom, then, is being able to be moral, to be good, to be upright and exemplify principles of virtue. On the other hand, vices and bad habits and immoral desires and temptations act as barriers, as burdens which cover up our true selves and which keep us from being true.
As I told Knobe after the colloquium, this view is deeply consonant with ancient Greek conceptions of the true self. Aristotle's notion of humanity as the rational animal with a particular telos, and the role of the moral life in accomplishing that telos; Plato's yearning for the liberation of the soul from the imprisoning snares of the material world unto the world of the Forms for endless contemplation, and the role of virtue in accomplishing this deliverance -- in all these cases morality is essentially connected to true identity, to being who you really are.
And as a professor commented at the colloquium, it is very sympathetic to a Christian metaphysic, as well. Humanity is made to reflect the image and likeness of God. Sin is hardly something natural or normal for humanity; it's a sickness and a disease and a defect which must be undone through union with Christ.