Dark Matter: The Issue of True Identity

Subject: Psychology
Pages: 2
Words: 405
Reading time:
2 min
Study level: Master


  • What constitutes one’s self? When one’s personality begins and ends? What are the origins of a person’s identity? These questions have been discussed in the fields of philosophy and psychology for centuries, and yet there is still no consensus on the topic of personal identity.
  • Body theory and memory theory provide opposing explanations of personal identity.
  • Thesis statement: If personal identity persists over time because a person remains in the same body or if it persists because an individual retains memories of themselves, in either case, Jason’s self from the original reality is his true self.

Definition of Personal Identity

  • Personal identity refers to properties defining individuals as themselves and distinguishing them from others.
  • Personal identity is characterized by persistence and continuation over time.
  • The question: a person at one point in time and a person at another point in time are the same person or two?

(The selected theories will provide disparate answers to this question)

Body Theory

  • One person has the same body throughout their life.
  • The body determines the persistence of one’s personality.
  • Even though Jasons from distinct realities look the same and may be viewed as the same person by others, their identities are different because their bodies are different.
  • Controversy: it is possible to presume that the identities of different Jasons are similar to the extent to which their bodies are similar.
  • The body theory does not take into account the fact that Jasons from disparate realities had different life experiences and were influenced by distinct external factors.

John Locke’s Memory Theory

  • Personal identity originates from consciousness, which is intrinsically connected to the process of thinking and remembering.
  • Memory links one’s present identity to his or her identity at earlier stages in life and, therefore, ensures identity continuation.
  • To a substantial extent, personality is defined by subjective experiences and external influences, whereas memory is a necessary prerequisite for a self to exist.
  • Jasons from different realities have disparate memories and, thus, their personalities are not the same.


  • One’s identity is defined by both psychological and biological continuity.
  • Although the selected theories do not provide exhaustive explanations of the concept of personal identity, they indicate that Jason from the original reality is not identical with Jasons from parallel realities.
  • Memory theory seems to be more valid since it implies that the development of individual identity depends on subjective experiences, sensations, and internal processes, whereas the body theory does not.