An alter ego (Latin for "other I") means alternative self, which is believed to be distinct from a person's normal or true original personality. Finding one's alter ego will require finding one's other self, one with different personality. A distinct meaning of alter ego is found in literary analysis used when referring to fictional literature and other narrative forms, describing a key character in a story who is perceived to be intentionally representative of the work's author (or creator), by virtue of oblique similarities, in terms of psychology, behavior, speech, or thoughts, often used to convey the author's own thoughts. The term is also sometimes, but less frequently, used to designate a hypothetical "twin" or "best friend" to a character in a story. Similarly, the term alter ego may be applied to the role or persona taken on by an actor or by other types of performers.
The existence of "another self" was first fully recognized in the 18th century, when Anton Mesmer and his followers used hypnosis to separate out the alter ego. These experiments showed a behavior pattern that was distinct from the personality of the individual when he was in the waking state compared with when he was under hypnosis. Another character had developed in the altered state of consciousness but in the same body.
Freud throughout his career would appeal to such instances of dual consciousness to support his thesis of the unconscious: He considered that “We may most aptly describe them as cases of a splitting of the mental activities into two groups, and say that the same consciousness turns to one or the other of these groups alternately”. Freud considered the roots of the phenomenon of the alter ego to be in the narcissistic stage of early childhood. Heinz Kohut would identify a specific need in that early phase for mirroring, by another which resulted later in what he called the “twinship or alter ego transference”.
Dissociate identity disorder
Alter ego is also used to refer to the different behaviors any person may display in certain situations. People suffering from dissociative identity disorder (DID) aren't aware of their other personality while people with alter ego are aware and are driven by it.
Bo Jackson struggled as a kid controlling his emotions and because of his anger he would get in trouble. His competitive and retaliating personality would get him penalties. One day he watched a movie, Friday the 13th and from that day he took on the character of Jason when he would take the football field. Letting Jason take over helped Bo Jackson become a relentless and disciplined destroyer on the field.
Tiffany Gee Lewis feels she's a lazy person at heart which is her weakness. She practices an exercise by creating a picture of her alter ego by drawing and naming her. By imagining her alter ego she can point out the bad habits consciously and notice them when they appear in her lifestyle. This exercise allows her to eradicate unhealthy habits that are hard to get away from. 
- The title characters in Robert Louis Stevenson's thriller Strange Case of Dr Jekyll and Mr Hyde represent an exploration of the concept that good and evil exist within one person, constantly at war. Edward Hyde literally represents the doctor's other self, a psychopath who is unrestrained by the conventions of civilized society, and who shares a body with the doctor. The names "Jekyll and Hyde" have since become synonymous with a split personality or an alter ego that becomes capable of overpowering the original self.
- Norman Douglas in the late 1890s wrote a short story, "The Familiar Spirit", about a man who became aware while drowning of a conformist second self – "the presence within him of this Spirit, his alter ego, which is bent on crushing his ambition".
- In comic books, superheroes and their secret identities are often considered alter egos. The archetypal comic book hero, Superman, assumes the identity of the "mild-mannered" newspaper reporter Clark Kent in order to live among the citizens of Metropolis without arousing suspicion. The Incredible Hulk comic book series further complicates this theme, as Bruce Banner loses control to the Hyde-like Hulk whenever he becomes angry, yet also depends upon the Hulk's super powers in order to combat villains. Comic book-inspired alter egos can be seen in other forms of popular fiction, including television and movie adaptations of comic books, parodies of this genre, and unrelated fictions.
- In the film Fight Club, the narrator, played by Edward Norton, has an alter ego he loses control of, Tyler Durden, played by Brad Pitt.
- Sonic the Hedgehog and Shadow the Hedgehog are considered as alter ego look-a-likes of each other.
- In Disney's Hannah Montana, Miley Stewart, played by Miley Cyrus, leads the life of high school student, and the life of teen pop sensation Hannah Montana allowing her to get the best of both worlds. Likewise, Miley's friends, Lilly Truscott, played by Emily Osment, and Oliver Oken, played by Mitchell Musso, also lead the lives of high school students, and are what makes up Hannah's entourage, Lola Luftnagle and Mike Stanley III respectively.
- In American Dad, Roger the Alien assumes various alter egos in order to go out in public without letting anyone finding out that he is a space alien.
- The popular YouTube personality, Miranda Sings, is the alter-ego of Colleen Ballinger.
- In Seinfeld, the character of George Costanza was revealed to be an alter-ego to the show creator Larry David.
This "see also" section may contain an excessive number of suggestions. Please ensure that only the most relevant links are given, that they are not red links, and that any links are not already in this article. (June 2018) (Learn how and when to remove this template message)
- Glenn Daniel Wilson (1991). Psychology and Performing Arts. Taylor & Francis. ISBN 90-265-1119-1.
- "Alter Ego". Collins English Dictionary - Complete and Unabridged 10th Edition. William Collins Sons & Co. Ltd. 2009. Retrieved 13 January 2013.
- J Haule, Jung in the 21st Century II (2010) p. 88
- Pedersen, David (1994). Cameral Analysis: A Method of Treating the Psychoneuroses Using Hypnosis. London, U.K.: Routledge. p. 20. ISBN 0-415-10424-6.
- S Freud, Five Lectures on Psycho-Analysis (Penguin 1995) p. 21
- S Freud On Metapsychology (PFL 11) p. 172
- S Freud, 'The Uncanny' Imago V (1919) p. 41
- H Kohut, How Does Analysis Cure? (London 1984) p. 192-3
- "What does it mean to have an Alter Ego? (Psychology)". Life Persona. Retrieved 2019-03-06.
- Herman, Todd (2019-02-05). The Alter Ego Effect: The Power of Secret Identities to Transform Your Life. HarperCollins. ISBN 9780062838674.
- Lewis, Tiffany Gee (2018-11-14). "Tiffany Gee Lewis: The battle against my alter ego". DeseretNews.com. Retrieved 2019-03-06.
- I. Ousby ed., The Cambridge Guide to Literature in English (Cambridge 1995) p. 263
- N. Douglas, Looking Back (London 1934) p. 274