The self is the subject of one's own experience of phenomena: perception, emotions, thoughts. In phenomenology, it is conceived as what experiences, and there isn't any experiencing without an experiencer, the self. The self is therefore an "immediate given", an intrinsic dimension of the fact of experiencing phenomena. In some other trends of philosophy, the self is instead seen as requiring a reflexive perception of oneself, the individual person, meaning the self in such a view is an object of consciousness.
The self has been studied extensively by philosophers and psychologists and is central to many world religions. With the recent rise in technology, the self has been discussed under various new emerging fields, such as Technoself Studies.
The philosophy of self seeks to describe essential qualities that constitute a person's uniqueness or essential being. There have been various approaches to defining these qualities. The self can be considered that being which is the source of consciousness; the agent responsible for an individual's thoughts and actions; and/or the substantial nature of a person which endures and unifies consciousness over time.
The philosophy of a disordered self, such as in schizophrenia, is described in terms of what the psychiatrist understands are actual events in terms of neuron excitation but are delusions nonetheless, and the schizo-affective or schizophrenic person also believes are actual events in terms of essential being. PET scans have shown that auditory stimulation is processed in certain areas of the brain, and imagined similar events are processed in adjacent areas, but hallucinations are processed in the same areas as actual stimulation. In such cases, external influences may be the source of consciousness and the person may or may not be responsible for "sharing" in the mind's process; and/or the events which occur, such as visions and auditory stimuli, may endure and be repeated often over hours, days, months or years—and the afflicted person may believe themselves to be in a state of rapture and/or possession.
The condition of the self is not static and/or finite but is a set of attributes which can be altered by an empirical stimuli becoming the strongest factor in behavior-forming, if recorded subconsciously. The healthier memory formation is conscious observation of the stimuli resulting in a learning process regarding the future qualification of the incoming impulse with a more encouraging attitude towards converting the logical system of the source.
The psychology of self is the study of either the cognitive and affective representation of one's identity or the subject of experience. The earliest formulation of the self in modern psychology forms the distinction between the self as I, the subjective knower, and the self as Me, the object that is known. Current views of the self in psychology position the self as playing an integral part in human motivation, cognition, affect, and social identity. Self following from John Locke has been seen as a product of episodic memory but research upon those with amnesia find they have a coherent sense of self based upon preserved conceptual autobiographical knowledge. It is increasingly possible to correlate cognitive and affective experience of self with neural processes. A goal of this ongoing research is to provide grounding and insight into the elements of which the complex multiply situated selves of human identity are composed. The 'Disorders of the Self' have also been extensively studied by psychiatrists.
For example, facial and pattern recognition take large amounts of brain processing capacity but pareidolia cannot explain many constructs of self for cases of disorder, such as schizophrenia or schizo-affective disorder.
One’s sense of self can be changed if they become part of a group that they consider stigmatized. According to Cox, Abramson, Devine, and Hollon (2012), if an individual has prejudice against a certain group, like the elderly and then later becomes part of this group this prejudice can be turned inward causing depression (i.e. deprejudice). 
Religious views on the self vary widely. The self is a complex and core subject in many forms of spirituality. Two types of self are commonly considered - the self that is the ego, also called the learned, superficial self of mind and body, an egoic creation, and the Self which is sometimes called the "True Self", the "Observing Self", or the "Witness".
Human beings have a self—that is, they are able to look back on themselves as both subjects and objects in the universe. Ultimately, this brings questions about who we are and the nature of our own importance. Traditions such as Buddhism see the apparent self (our identification as souls, minds, bodies and egos) as a "grasping-after" self—i.e., in as much as one has a "self," one has it only through a deluded attempt to shore it up. Christianity makes a distinction between the true self and the false self, and sees the false self negatively, distorted through sin: 'The heart is deceitful above all things, and desperately wicked; who can know it?' (Jeremiah 17:9)
According to Marcia, identity comes from both political and religious views. He also identified exploration and commitment as interactive parts of identity formation, which includes religious identity. Erik Erikson compared faith with doubt and found that healthy adults take heed to their spiritual side.
One description of spirituality is the self's search for "ultimate meaning" through an independent comprehension of the sacred. Spiritual identity appears when the symbolic religious and spiritual value of a culture is found by individuals in the setting of their own life. There can be different types of spiritual self because it is determined on one's life and experiences. Another definition of spiritual identity is " a persistent sense of self that addresses ultimate questions about the nature, purpose, and meaning of life, resulting in behaviors that are consonant with the individual’s core values." 
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