Split personality or split-self..?

I prefer split-self to split personality. Psychologist describes a person with split personality as a person who is not stable mentally. But everybody changes over time and in many ways when change is the theme for his survival and protection. In other words everybody has a split self in himself as a form of security. Meaning we can adapt or we can split our self to all types of self when comes to a change in the environmental factors either physical, nature, culture, or mental. An that explain why a person can write on all topics when he seeks something to be written. The reason then is in the natural ability of one self to automatically split the self to whoever persons and personality he wants to be and thus the production of a written work or the display of the character. Sounds logic or sounds crazy..? Neither logic nor crazy but splitting through one's self in order to survive..