• I can imagine waking up with a
different body.
• So it is flase that :
– Different body → different person.
• Same body is not a necessary
condition for personal identity.
Generally, it is the unique numerical identity of persons through time.[3][4] That is to say, the necessary and sufficient conditions under which a person at one time and a person at another time can be said to be the same person, persisting through time.[note 5] In the modern philosophy of mind, this concept of personal identity is sometimes referred to as the diachronic problem[note 6] of personal identity.[5] The synchronic problem[note 7] is grounded in the question of what features or traits characterize a given person at one time.
Identity is an issue for both continental philosophy and analytic philosophy. A question in continental philosophy is in what sense can the contemporary conception of identity be maintained, while many prior propositions, postulates, and presuppositions about the world are different.[6][7]