The task of personal identity is to define a quality of a human, which makes him or her a unique self. Emotions like remorse and pride presuppose a personal identity that persists through time. Can someone feel remorseful or happy about his or her actions yesterday or few years ago even if they have no notion of a personal identity?
This whole idea of responsibility requires a persisting personal identity; otherwise one cannot be held responsible for any act committed by him or her if that person is not the same person he or she is now. Like in the example of the box of Kleenex, which was reduced to ashes and seeing that similar box in a store or at home. It would be absurd to say that it is the same box that was burnt. Even with absolute similarity, it is not possible to say that the two things are same without considering some external or internal perspectives. We believe in the continuity of the self but we are not sure what this self contains of. We are not sure what leads to the continuity of this very self. What element persists through time to produce this feeling of continuity? Is it soul continuity, a memory continuity or brain continuity?
The three theories of personal identity, the soul theory, the memory theory and