What is Egoism / an egoist?

"Egocentrism is the inability to differentiate between self and other. More specifically, it is the inability to untangle subjective schemas from objective reality; an inability to understand or assume any perspective other than their own.
Although egocentrism and narcissism appear similar, they are not the same. A person who is egocentric believes they are the center of attention, like a narcissist, but does not receive gratification by one's own admiration. An egotist is a person whose ego is greatly influenced by the approval of others while a narcissist is not."

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More Info...

1. Piaget's Definition of Egocentrism in Adolescence: Examples & Overview - Video & Lesson Transcript | Study.com
2. Adolescent Egocentrism uploaded by Stephanie Shaw @ YouTube
3. Elkind's Theory of Adolescent Egocentrism - Video & Lesson Transcript | Study.com
4. Throwback Tuesday: Teaching beyond egocentrism and sociocentrism – Education to Save the World
5. Motives of Egocentric Thinking
6. Egocentrism uploaded by jenningh @  YouTube
7. Tutorial: Cognitive Egocentrism Theory Of Mind
8. It’s a Fine Line Between Narcissism and Egocentrism | Psychology Today
9. Egocentrism definition | Psychology Glossary | alleydog.com
10. Preoperational Stage - Egocentrism | Simply Psychology